mrs-fcv6n1 draft.qxd 7/19/2011 10:04 AM Page 1mrs.org.sg/outlook/MRS-S-OUTLOOK Vol6 No1_Final.pdf · The method works with the four differ- ... their widespread technological application

To spread information and knowledge and to promote collaboration in the area of Materials Research, Engineering

and Technology amongst the members of MRS-S

Vol 6 w No. 1 w July - Sept., 2011 | ISSN 1793-3609

Ø MRS-S Activities: Past, Present and Future

The Materials Research Society of Singapore (MRS-S) organized five International andfour National Conferences in Singapore since 2001. The biennial 'InternationalConference on Materials for Advanced Technologies (ICMAT)' series were held in 2001,2003, 2005, 2007 and 2009.

The biennial National Conferences were held in 2004, 2006, 2008 and 2010.

MRS-S also sponsored/supported several other conferences, workshops, symposia andpublic lectures. To reach out to the public, MRS-S has organized number of public lec-tures by Nobel Laureates and also an Astronaut.

Medals & Bursaries: MRS-S instituted gold medals for the best outgoing students inMaterials Science at the National University of Singapore (NUS) and NanyangTechnological University (NTU). It instituted the 'MRS Singapore Student BursaryFund' at the NUS. MRS-S also instituted the 'MRS-S Book Prize' at the 'RepublicPolytechnic' of Singapore. This yearly Book Prize will be awarded to the top final-yearstudent graduating with the 'Diploma in Materials Science'. MRS-S recently institutedthe medal for the best Ph.D. Thesis in the Physics Department of NUS.

Awards: Prof Shih Choon Fong, the founding President of MRS-S, has been chosen andreceived the 'Outstanding Service Award' of the NUS for the year 2011. He is nowFounding President and Professor of Mechanical Engineering, King AbdullahUniversity of Science and Technology, Saudi Arabia.

Prof. J.J. Vittal, MRS-S Executive committee member, has been chosen and received the'Outstanding Researcher Award' of the NUS for the year 2011. He is at the ChemistryDept. of the NUS.

Dr. Ramam Akkipeddi, MRS-S Executive committee member, has been chosen andreceived the 'STAR Employee Award' for the year 2011given by A*STAR (Agency forScience, Technology and Research, Singapore). Dr. Akkipeddi is the Head of the SERCNano-Fabrication, Processing and Characterization (SnFPC) group at the Institute ofMaterials Research and Engineering (IMRE).

Hearty Congratulations to the above three MRS-S Members.

The ICMAT 2011 will be held in Singapore during 26,June to 1, July, 2011. It will have40 Symposia, comprising the areas of Nanoscience and Technology, Energy andEnvironment, Functional Materials, Bio/Soft Materials, Imaging, Crystal Growth andCrystal Technology and Interdisciplinary. There will be nine Plenary Talks and threeTheme Lectures, and two Public Lectures (by Nobel laureates).

Incorporation of 4th Asian Nanoimprint Lithiography Symposium (ASNIL),Nanoformulation 2011, Crystal Growth and Crystal Technology-5 and organization of'Young Scientists Workshop' and Industry Workshops on 'Applied SurfaceEngineering', 'Microelectronic Process and Package Characterization and ReliabilityAnalysis', and 'Teaching the Nano Scale: A Global Revolution in Science Education - anEducation Forum and Open Discussion', are some of the new initiatives of the ICMAT2011 conference. About 3000 delegates are expected.

Details of the various Symposia and other relevant information can be found at the web-site: http://www.mrs.org.sg/icmat2011/

C O N T E N T SC O N T E N T SHighlightHighlights of previous ICMAs of previous ICMATT

ConferencesConferences

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HighlightHighlights of previous Nationals of previous National

ConferencesConferences

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HighlightHighlights of the Recents of the Recent

Literature Literature

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Recent BooksRecent Books

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MRS-S MembershipMRS-S Membership


Review Review ArticlesArticles


Forthcoming ConferencesForthcoming Conferences


Materials Education &Materials Education &

Research in Singapore Research in Singapore


InvitInvitation to MRS-S Membersation to MRS-S Members


© 2011 MRS-S, Singapore. All rights reserved.

mrs-fcv6n1_draft.qxd 7/19/2011 10:04 AM Page 1

Volume 6• No.1• July–Sept., 2011 MRS-S OUTLOOKH

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MRS-S Executive Committee(For 2011–2012)

PresidentB. V. R. Chowdari, NUS

Founding PresidentShih Choon Fong, KAUST

Vice PresidentsAndrew Wee, T.S., NUS

Ma Jan, NTU

SecretaryJoachim S.C. Loo, NTU

Joint SecretaryDing Jun, NUS

TreasurerFENG Yuan Ping, NUS

Joint TreasurerRamam, Akkipeddi, IMRE

MembersChia Ching Kean, IMRE

Ho Ghim Wei, NUSLiu Zishun , IHPC

Ng Teng Yong, NTUS. Shannigrahi, IMREShen Ze Xiang, NTU

J.J. Vittal , NUSWan Andrew Chwee Aun, IBN

P.K. Wong, ICES

Honorary AuditorsKaren CHONG , IMREStefan ADAMS, NUS

NUS: National University of SingaporeNTU: Nanyang Technological University, SingaporeIBN: Institute of Bioengineering and Nanotechnology, SingaporeICES: Institute of Chemical and Environmental Sciences, SingaporeIHPC: Institute of High Performance Computing, SingaporeIMRE: Institute of Materials Research & Engineering, SingaporeKAUST: King Abdulla University of Science & Technology,Saudi Arabia

Highlights of Previous ICMAT Conferences

Year 2001:1–6, July 2001; 16 Symposia; 10 PlenaryLectures; 4 Public Lectures by Nobel Laureates; 1400delegates; 18 Best Poster Awards; 36 Exhibitors.

Year 2003:7–12, Dec., 2003; 16 Symposia; 9 PlenaryLectures; 2 Public Lectures by Nobel Laureates; 1500delegates; 19 Best Poster Awards; 29 Exhibitors.

Year 2005: 3–8, July 2005; 25 Symposia; 9 Ple-nary Lectures; 2 Theme Lectures; 3 Public Lecturesby Nobel Laureates; 2200 Delegates; 28 Best PosterAwards; 43 Exhibitors.

Year 2007: 1–6, July 2007; 18+6 Symposia; 9 Ple-nary Lectures; 2 Theme Lectures; 2 Public Lecturesby Nobel Laureates; 2300 Delegates; 25 Best PosterAwards; 41 Exhibitors.

Year 2009: 28 June.–3, July 2009; 23 Symposia, 9Plenary and 3 Theme Lectures, 3 Public Lectures byNobel Laureates; 2170 Participants; 37 Best PosterAwards; 43 Exhibitors.

Highlights of Previous National Conferences

Year 2004:6 Aug., 2004; 20 Invited Talks; 130 PosterPapers; 4 Best Poster Awards.

Year 2006: 18–20, Jan., 2006; Includes the Sympo-sium on ‘Physics and Mechanic of Advanced Mate-rials’; 60 Invited Talks; 200 Poster Papers; 1 PublicLecture; 5 Best Poster Awards.

Year 2008:Feb., 25–27, 2008. Incorporated the MRS-IMumbai (India)-Chapter Joint Indo-Singapore Meet-ing; 2 Keynote Talks, 60 Invited Talks; 211 PosterPapers; 10 Best Poster Awards.

Year 2010: March, 17–19, 2010. 1 Keynote Talk, 26Invited Talks; 137 Poster Papers; 7 Best Poster Awards.

MRS-S OUTLOOK (ISSN 1793-3609) is published quarterly by the Materials Research Society of Singapore (MRS-S),

c/o Institute of Materials Research & Engineering, 3, Research Link, Singapore 117 602.

Editor: G.V. Subba Rao.Disclaimer: Statements and opinions expressed in ‘MRS-S OUTLOOK’ are solely those of the

authors, and do not reflect those of MRS-S, nor the editor and staff. Permissions:The subject matter contained in ‘MRS-S

OUTLOOK’ can be freely reproduced for not-for-profit use by the readers; however, a word of acknowledgement will be

appreciated.

A Quarterly publication by the Materials Research Society of Singaporepage 2

MRS-S OUTLOOK Volume 6• No.1• July–Sept., 2011

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Highlights of Recent Literature

(Contributed by the Editor)

Layer-by-Layer Removal of Graphene forDevice Patterning

The patterning of graphene is useful in fabricat-ing electronic devices, but existing methods do notallow control of the number of layers of graphenethat are removed. Here, Dimievet al [1] show thatsputter-coating graphene and graphene-like materialswith zinc and dissolving the latter with dilute acidremoves one graphene layer and leaves the lower lay-ers intact. The method works with the four differ-ent types of graphene and graphene-like materials:graphene oxide, chemically converted graphene, chem-ical vapor–deposited graphene, and micromechanicallycleaved (“clear-tape”) graphene. On the basis of thedata, the top graphene layer is damaged by the sputter-ing process, and the acid treatment removes the dam-aged layer of carbon. When used with predesigned zincpatterns, this method can be viewed as lithography thatetches the sample with single-atomic-layer resolution.

Reference

1. A. Dimiev, D. V. Kosynkin, A. Sinitskii, A. Slesarev,Z. Sun and J. M. Tour,Science, 331 (6021), 1168–1172(2011) (4 Mar., Issue).

The Bonding Electron Density in Aluminum

Aluminum (Al) metal is considered to approach an“ideal” metal or free electron gas. The valence elec-trons move freely, as if unaffected by the presenceof the metal ions. Therefore, the electron redistribu-tion due to chemical bonding is subtle and has provenextremely difficult to determine. Experimental mea-surements and ab initio calculations have yielded sub-stantially different results.

Nakashima et al [1] applied quantitativeconvergent-beam electron diffraction to Al to pro-vide an experimental determination of the bondingelectron distribution. Calculation of the electron dis-tribution based on density functional theory is shown

to be in close agreement. The results yield an accu-rate quantitative correlation between the anisotropicelastic properties of Al and the bonding electron andelectrostatic potential distributions.

Reference

1. P. N. H. Nakashima, A. E. Smith, J. Etheridge andB. C. Muddle, Science, 331 (6024), 1583–1586 (2011)(25 Mar., Issue).

Magnetic and non-magnetic phases of aquantum spin liquid

A quantum spin-liquid phase is an intriguing pos-sibility for a system of strongly interacting mag-netic units in which the usual magnetically orderedground state is avoided owing to strong quantumfluctuations.It was first predicted theoretically fora triangular-lattice model with antiferromagneticallycoupledS = 1/2 spins. The layered molecular systemκ-(BEDT-TTF)2Cu2(CN)3 is a Mott insulator with analmost isotropic, triangular magnetic lattice of spin-1/2BEDT-TTF dimers that provides a prime example of aspin liquid.. Despite a high-temperature exchange cou-pling, J, of 250 K, no obvious signature of conventionalmagnetic ordering is seen down to 20 mK.

Here, Prattet al [1] show, using muon spin rota-tion, that applying a small magnetic field to this sys-tem produces a quantum phase transition between thespin-liquid phase and an antiferromagnetic phase witha strongly suppressed moment. This can be describedas Bose–Einstein condensation of spin excitations withan extremely small spin gap. At higher fields, a sec-ond transition is found that suggests a threshold forde-confinement of the spin excitations. These studiesreveal the low-temperature magnetic phase diagramand enable the measurement of characteristic criticalproperties. The authors also compare the results closelywith current theoretical models.

A Quarterly publication by the Materials Research Society of Singapore page 3


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ture Reference

1. F. L. Pratt, P. J. Baker, S. J. Blundell, T. Lancaster,S. Ohira-Kawamura, C. Baines, Y. Shimizu, K. Kanoda,I. Watanabe and G. Saito, Nature, 471 (7340), 612-616(2011) (31 Mar., Issue).

Spontaneous Ferroelectric Order in aBent-Core Smectic Liquid Crystal of FluidOrthorhombic Layers

Macroscopic polarization density, characteristic of fer-roelectric phases, is stabilized by dipolar intermolec-ular interactions. These are weakened as materialsbecome more fluid and of higher symmetry, limitingferroelectricity to crystals and to smectic liquid crystalstackings of fluid layers.

Here, Reddyet al [1] report on the SmAPF, thesmectic of fluid polar orthorhombic layers that orderinto a three-dimensional (3D) ferroelectric state, thehighest-symmetry layered ferroelectric possible andthe highest-symmetry ferroelectric material found todate. Its bent-core molecular design employs a sin-gle flexible tail that stabilizes layers with untiltedmolecules and in-plane polar ordering, evident inmonolayer-thick freely suspended films. Electro-opticresponse reveals the 3D- orthorhombic ferroelectricstructure, stabilized by silane molecular terminationsthat promote parallel alignment of the moleculardipoles in adjacent layers.

Reference1. R. A. Reddy, C. Zhu, R. Shao, E. Korblova, T. Gong,

Y. Shen, E. Garcia, M. A. Glaser, J. E. Maclennan,D. M. Walba and N. A. Clark,Science, 332(6025), 72–77(2011) (1 Apr., Issue).

Heavily Doped Semiconductor NanocrystalQuantum Dots

Doping of semiconductors by impurity atoms enabledtheir widespread technological application in micro-electronics and optoelectronics. However, doping hasproven elusive for strongly confined colloidal semicon-ductor nanocrystals because of the synthetic challengeof how to introduce single impurities, as well as a lackof fundamental understanding of this heavily dopedlimit under strong quantum confinement.

Mocattaet al [1] developed a method to dope semi-conductor nanocrystals with metal impurities, enabling

control of the band gap and Fermi energy. A com-bination of optical measurements, scanning tunnelingspectroscopy, and theory revealed the emergence of aconfined impurity band and band-tailing. The methodyields n- and p-doped semiconductor nanocrystals,which have potential applications in solar cells, thin-film transistors, and optoelectronic devices.

Reference1. D. Mocatta, G. Cohen, J. Schattner, O. Millo, E. Rabani

and U. Banin ,Science, 332(6025), 77–81 (2011) (1 Apr.,Issue).

Intrinsically Colored and Luminescent Silk

Here, Tansilet al [1] demonstrated an in vivo uptake ofdyes into domesticated silkworms, leading to the directproduction of intrinsically colored silk by the silk-worms. The colored silk has been achieved by addingappropriate dyes into silkworm feed with minimalinterference to standard sericulture procedure, thusmaking this method applicable for large-scale produc-tion of colored silk by the silkworms.

A series of fluorescent dyes were successfullyused as model compounds to investigate and under-stand their selective uptake into fibroin or sericinthrough fluorescence imaging and spectroscopic quan-tification. The authors state that, ‘when applied toother compounds with similar molecular properties,this process can potentially lead to functional silk forvarious biomedical applications including tissue engi-neering and bioelectronic, bio-optic, and biomicroflu-idic devices’.

Reference1. N. C. Tansil, Y. Li, C. P. Teng, S. Zhang, K. Y. Win,

X. Chen, X. Y. Liu and M.-Y. Han,Adv. Mater., 23 (12)1463–1466 (2011).

High-Frequency, Scaled Graphene Transistorson Diamond-Like Carbon

Owing to its high carrier mobility and saturation veloc-ity, graphene has attracted enormous attention in recentyears. In particular, high-performance graphene tran-sistors for radio-frequency (r.f.) applications are ofgreat interest. Synthesis of large-scale graphene sheetsof high quality and at low cost has been demonstratedusing chemical vapour deposition (CVD) methods.



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reHere, Wu et al [1] report the systematic studyof top-gated CVD-graphene r.f. transistors with gatelengths scaled down to 40 nm, the shortest gate lengthdemonstrated on graphene r.f. devices. The CVDgraphene was grown on copper film and transferredto a wafer of diamond-like carbon. Cut-off frequenciesas high as 155 GHz have been obtained for the 40-nmtransistors, and the cut-off frequency was found toscale as 1/(gate length). Unlike conventional semicon-ductor devices where low-temperature performance ishampered by carrier freeze-out effects, the r.f. per-formance of the above graphene devices exhibits lit-tle temperature dependence down to 4.3 K, providinga much larger operation window than is available forconventional devices.

Reference

1. Y. Wu, Y.-M. Lin, A. A. Bol, K. A. Jenkins, F. Xia,D. B. Farmer, Y. Zhu and P. Avouris, Nature, 472(7341),74–78 (2011) (7 Apr., Issue).

Surface-Plasmon Holography withWhite-Light Illumination

The recently emerging three-dimensional (3D) dis-plays in the electronic shops imitate depth illusion byoverlapping two parallax 2D images through eitherpolarized glasses that viewers are required to wear orlenticular lenses fixed directly on the display. Holog-raphy, on the other hand, provides real 3D imaging,although usually limiting colors to monochrome. Theso-called rainbow holograms—mounted, for exam-ple, on credit cards—are also produced from parallaximages that change color with viewing angle.

Here, Ozakiet al [1] report on a holographic tech-nique based on surface plasmons that can reconstructtrue 3D color images, where the colors are recon-structed by satisfying resonance conditions of surfaceplasmon polaritons for individual wavelengths. Suchreal 3D color images can be viewed from any angle,just like the original object.

Reference

1. M. Ozaki, J.–I. Kato and S. Kawata,Science,332(6026),218–220 (2011) (8 April Issue).

Oriented 2D Covalent Organic FrameworkThin Films on Single-Layer Graphene

Covalent organic frameworks (COFs), in whichmolecular building blocks form robust microporousnetworks, are usually synthesized as insoluble andunprocessable powders. Colsonet al [1] have growntwo-dimensional (2D) COF films on single-layergraphene (SLG) under operationally simple solvother-mal conditions. The layered films stack normal to theSLG surface and show improved crystallinity com-pared with COF powders.

The authors used SLG surfaces supported on cop-per, silicon carbide, and transparent fused silica (SiO2)

substrates, enabling optical spectroscopy of COFs inthe transmission mode. Three chemically distinct COFfilms grown on SLG exhibit similar vertical alignmentand long-range order, and two of these are of interestfor organic electronic devices for which thin-film for-mation is a prerequisite for characterizing their opto-electronic properties.

Reference

1. J. W. Colson, A. R. Woll, A. Mukherjee, M. P. Levendorf,E. L. Spitler, V. B. Shields, M. G. Spencer, J. Park andW. R. Dichtel,Science,332 (6026), 228–231 (2011) (8April Issue).

Air-Stable Magnesium NanocompositesProvide Rapid and High-Capacity HydrogenStorage without using Heavy-Metal Catalysts

Jeonet al [1] have developed a new, simple methodto synthesize air-stable crystalline Mg nanocrystals(NCs)/poly (methyl methacrylate) (PMMA) compos-ites by encapsulation in a polymer with selective gaspermeability, protecting the NCs from O2 and H2O.The Mg NCs/PMMA composites impressively showedno oxidation after two weeks of air exposure. Rapiduptake (<30min at 200C) of hydrogen was achievedwith a high capacity (∼6 wt% in Mg,∼4% overall) inthe absence of heavy-metal catalysts, demonstrating avolumetric capacity (55 g/l) greater than that of com-pressed H2 gas.

Theoretical modelling of the experimental datawith a Johnson–Mehl–Avrami model indicates thathydrogenation of Mg NCs proceeds through onedimensional (1D) growth, which can occur along line



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ture defects in the Mg NCs. The authors state that, ‘this

approach of synthesizing nanosized air-sensitive metalnanocrystals protected in a gas-selective polymer, pro-vides new opportunities in low-cost high-capacityhydrogen storage media, batteries and fuel cells.

Reference

1. K.-J. Jeon, H. R. Moon, A. M. Ruminski, B. Jiang,C. Kisielowski, R. Bardhan and J. J. Urban,NatureMater.,10 (4), 286–290 (2011).

Optically Healable Supramolecular Polymers

Polymers with the ability to repair themselves aftersustaining damage could extend the lifetimes of mate-rials used in many applications. Most approaches tohealable materials require heating the damaged area.

Here, Burnworth et al [1] present metallo-supramolecular polymers that can be mended throughexposure to light. They consist of telechelic, rubbery,low-molecular-mass polymers with ligand end groupsthat are non-covalently linked through metal-ion bind-ing. On exposure to ultraviolet light, the metal–ligandmotifs are electronically excited and the absorbedenergy is converted into heat. This causes temporarydisengagement of the metal–ligand motifs and a con-comitant reversible decrease in the polymers’ molec-ular mass and viscosity, thereby allowing quick andefficient defect healing. Light can be applied locallyto a damage site, so objects can in principle be healedunder load. The authors, ‘anticipate that this approachto healable materials, based on supramolecular poly-mers and a light–heat conversion step, can be appliedto a wide range of supramolecular materials that usedifferent chemistries’.

Reference

1. M. Burnworth, L. Tang, J. R. Kumpfer, A. J. Duncan,F. L. Beyer, G. L. Fiore, S. J. Rowan and C. Weder,Nature, 472(7343), 334–337 (2011) (21 Apr., Issue).

High-Performance Electrocatalysts forOxygen Reduction Derived from Polyaniline,Iron, and Cobalt

The prohibitive cost of platinum (Pt) for catalyzing thecathodic oxygen reduction reaction (ORR) has ham-pered the widespread use of polymer electrolyte fuel

cells. Here, Wuet al [1] describe a family of non–precious metal catalysts that approach the performanceof Pt-based systems at a cost sustainable for high-power fuel cell applications, possibly including auto-motive power.

The approach uses polyaniline as a precursor toa carbon-nitrogen template for high-temperature syn-thesis of catalysts incorporating iron and cobalt. Themost active materials in the group catalyze the ORR atpotentials within∼60 millivolts of that delivered bystate-of-the-art carbon-supported-Pt, combining theirhigh activity with remarkable performance stability fornon–precious metal catalysts (700 h at a fuel cell volt-age of 0.4V) as well as excellent four-electron selectiv-ity (hydrogen peroxide yield<1.0%).

Reference

1. G. Wu, K. L. More, C. M. Johnston and P. Zelenay,Sci-ence,332(6028), 443–447 (2011) (22 Apr., Issue).

Topological Phase Transition and TextureInversion in a Tunable Topological Insulator

Topological insulators in three dimensions (3D) arenonmagnetic insulators with novel surface states thatare a consequence of the nontrivial topology of elec-tronic wave functions in the bulk of the materials. Therecently discovered 3D or bulk topological insulatorsare expected to exhibit exotic quantum phenomena. Itis believed that a trivial insulator can be twisted into atopological state by modulating the spin-orbit interac-tion or the crystal lattice, driving the system through atopological quantum phase transition.

By directly measuring the topological quantumnumbers and invariants, Xuet al [1] report the obser-vation of a phase transition in a tunable spin-orbit sys-tem, BiTl(S1–δSeδ)2, in which the topological stateformation is visualized. In the topological state, vortex-like polarization states are observed to exhibit 3D vec-torial textures, which collectively feature a chiralitytransition as the spin momentum–locked electrons onthe surface go through the zero carrier density point.The authors state that,’such phase transition and tex-ture inversion can be the physical basis for observingfractional charge (±e/2) and other fractional topologi-cal phenomena.



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1. S.-Y. Xu, Y. Xia, L. A. Wray, S. Jia, F. Meier, J. H. Dil,J. Osterwalder, B. Slomski, A. Bansil, H. Lin, R. J. Cavaand M. Z. Hasan,Science,332 (6029), 560–564 (2011)(29 Apr., Issue).

Low-Power Switching of Phase-ChangeMaterials with Carbon Nanotube Electrodes

Phase-change materials (PCMs) like, Ge2Sb2Te5

(GST), are promising candidates for nonvolatile datastorage and reconfigurable electronics, but high pro-gramming currents have presented a challenge to real-ize low-power operation.

Here, Xiong et al [1] report the realization ofcontrolled PCM bits of GST with single-wall andsmall-diameter multi-wall carbon nanotubes. This con-figuration achieves programming currents of 0.5µa(set) and 5µa (reset), two orders of magnitude lowerthan present state-of-the-art devices. Pulsed measure-ments enable memory switching with very low energyconsumption. Analysis of over 100 devices finds thatthe programming voltage and energy are highly scal-able and could be below 1 volt and single femtojoulesper bit, respectively.

Reference

1. F. Xiong, A. D. Liao, D. Estrada and E. Pop,Science,332(6029), 568–570 (2011) (29 Apr., Issue).

Low-Voltage, Low-Power, OrganicLight-Emitting Transistors for Active MatrixDisplays

Intrinsic non-uniformity in the polycrystalline-siliconbackplane transistors of active matrix organic light-emitting diode displays severely limits display size.Organic semiconductors might provide an alternative,but their mobility remains too low to be useful in theconventional thin-film transistor design.

Here, McCarthyet al [1] demonstrate an organicchannel light-emitting transistor operating at low volt-age, with low power dissipation, and high apertureratio, in the three primary colors. The high level of per-formance is enabled by a single-wall carbon nanotubenetwork source electrode that permits integration of thedrive transistor and the light emitter into an efficientsingle stacked device. The performance demonstrated

is comparable to that of polycrystalline-silicon back-plane transistor-driven display pixels.

Reference

1. M. A. McCarthy, B. Liu, E. P. Donoghue, I. Kravchenko,D. Y. Kim, F. So and A. G. Rinzler,Science,332 (6029),570–573 (2011) (29 Apr., Issue).

Convergence of Electronic Bands for HighPerformance Bulk Thermoelectrics

Many different concepts have been used in the searchfor new materials with high thermoelectric efficiency,such as the use of nano-structuring to reduce phononthermal conductivity, which has led to the investiga-tion of a variety of complex material systems. It is wellknown that a high valley degeneracy (typically≤6 forknown thermoelectrics) in the electronic bands is con-ducive to high zT (thermoelectric figure of merit), andthis in turn has stimulated attempts to engineer suchdegeneracy by adopting low-dimensional nanostruc-tures.

Here, Peiet al [1] demonstrate that it is possibleto direct the convergence of many valleys in a bulkmaterial by tuning the doping and composition. Bythis route, they achieved a convergence of at least 12valleys in Na-doped Pb(Te1−xSex) alloys, leading toan extraordinary zT value of 1.8 at about 850 K. Theauthors state that, ‘band engineering to converge thevalence (or conduction) bands to achieve high valleydegeneracy should be a general strategy in the searchfor, and improvement of bulk thermoelectric materials,because it simultaneously leads to a high Seebeck coef-ficient and high electrical conductivity’.

Reference

1. Y. Pei, X. Shi, A. LaLonde, H. Wang, L. Chen andG. J. Snyder,Nature, 473 (7345), 66–69 (2011) (5May,Issue).

Beating Crystallization in Glass-FormingMetals by Millisecond Heating and Processing

The development of metal alloys that form glasses atmodest cooling rates has stimulated broad scientificand technological interest. However, intervening crys-tallization of the liquid in even the most robust bulkmetallic glass-formers is orders of magnitude faster



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ture than in many common polymers and silicate glass-

forming liquids. Crystallization limits experimentalstudies of the undercooled liquid and hampers effortsto plastically process metallic glasses.

Johnsonet al [1] have developed a method torapidly and uniformly heat a metallic glass at rates of106 K/sec to temperatures spanning the undercooledliquid region. Liquid properties are subsequently mea-sured on millisecond time scales at previously inac-cessible temperatures under near-adiabatic conditions.Rapid thermoplastic forming of the undercooled liquidinto complex net shapes is implemented under rheo-logical conditions typically used in molding of plastics.By operating in the millisecond regime, the authors areable to “beat” the intervening crystallization and suc-cessfully process even marginal glass-forming alloyswith very limited stability against crystallization thatare not processable by conventional heating.

Reference

1. W. L. Johnson, G. Kaltenboeck, M. D. Demetriou,J. P. Schramm, X. Liu, K. Samwer, C. P. Kim andD. C. Hofmann,Science,332(6031), 828–833 (2011) (13May, Issue).

Three-Dimensional Orientation Mapping inthe Transmission Electron Microscope

Over the past decade, efforts have been madeto develop nondestructive techniques for three-dimensional (3D) grain-orientation mapping in crys-talline materials. 3D x-ray diffraction microscopy anddifferential-aperturex-ray microscopy can now be usedto generate 3D orientation maps with a spatial resolu-tion of 200 nm.

Here, Liuet al [1] describe a nondestructive tech-nique that enables 3D orientation mapping in thetransmission electron microscope of mono- and multi-phase nano-crystalline materials with a spatial resolu-tion reaching 1 nm. They demonstrate the technique byan experimental study of a nano-crystalline aluminumsample and use simulations to validate the principlesinvolved.

Reference

1. H. H. Liu, S. Schmidt, H. F. Poulsen, A. Godfrey,Z. Q. Liu, J. A. Sharon and X. Huang ,Science,332(6031), 833–834 (2011) (13 May, Issue).

Dimensionality Control of Electronic PhaseTransitions in Nickel-Oxide Superlattices

The competition between collective quantum phasesin materials with strongly correlated electrons dependssensitively on the dimensionality of the electron sys-tem, which is difficult to control by standard solid-statechemistry.

Here, Boris et al [1] have fabricated superlat-tices of the paramagnetic metal lanthanum nicke-late (LaNiO3) and the wide-gap insulator lanthanumaluminate (LaAlO3) with atomically precise layersequences. They used optical ellipsometry and low-energy muon spin rotation to show that superlatticeswith LaNiO3, as thin as two unit cells, undergo asequence of collective metal-insulator and antiferro-magnetic transitions as a function of decreasing tem-perature, whereas samples with thicker LaNiO3 layersremain metallic and paramagnetic at all temperatures.The authors conclude that, ‘metal-oxide superlatticesthus allow control of the dimensionality and collectivephase behavior of correlated-electron systems’.

Reference

1. A. V. Boris, Y. Matiks, E. Benckiser, A. Frano,P. Popovich, V. Hinkov, P. Wochner, M. Castro-Colin,E. Detemple, V. K. Malik, C. Bernhard, T. Prokscha,A. Suter, Z. Salman, E. Morenzoni, G. Cristiani,H.-U. Habermeier and B. Keimer,Science,332 (6032),937–940 (2011) (20 May Issue).

Competition of Superconducting Phenomenaand Kondo Screening at the Nanoscale

Magnetic and superconducting interactions coupleelectrons together to form complex states of mat-ter. Here, Frankeet al [1]show that, at the atomicscale, both types of interactions can coexist andcompete to influence the ground state of a local-ized magnetic moment. Local spectroscopy at 4.5 Kshows that the spin-1 system formed by manganese-phthalocyanine (MnPc) adsorbed on Pb(111) can liein two different magnetic ground states. These aredetermined by the balance between Kondo screeningand superconducting pair-breaking interactions. Bothground states alternate at nm- length scales to form aMoire-like superstructure. The quantum phase transi-tion connecting the two (singlet and doublet) ground



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1. K. J. Franke, G. Schulze, and J. I. Pascual,Science,332(6032), 940–944 (2011) (20 May Issue).

Chlorinated Indium Tin Oxide Electrodeswith High Work Function for Organic DeviceCompatibility

In organic light-emitting diodes (OLEDs), a stack ofmultiple organic layers facilitates charge flow from thelow work function [∼4.7 eV] of the transparent elec-trode (tin-doped indium oxide, ITO) to the deep energylevels (∼6 eV) of the active light-emitting organicmaterials. Here, Helanderet al [1] demonstrate a chlo-rinated ITO transparent electrode with a work functionof >6.1 eV that provides a direct match to the energylevels of the active light-emitting materials in state-of-the art OLEDs.

A highly simplified green OLED with a max-imum external quantum efficiency (EQE) of 54%and power efficiency of 230 lumens/watt using out-coupling enhancement was demonstrated, as wereEQE of 50% and power efficiency of 110 lumens/wattat 10,000 candelas/m2.

Reference

1. M. G. Helander, Z. B. Wang, J. Qiu, M. T. Greiner,D. P. Puzzo, Z. W. Liu, and Z. H. Lu,Science,332(6032),944–947 (2011) (20 May Issue).

Improved Measurement of the Shape of theElectron

The electron is predicted to be slightly aspheric, with adistortion characterized by the electric dipole moment(EDM), de. No experiment has ever detected this devi-ation. The standard model of particle physics predictsthat de is far too small to detect, being some elevenorders of magnitude smaller than the current exper-imental sensitivity. However, many extensions to thestandard model naturally predict much larger values ofde that should be detectable. This makes the search for

the electron EDM a powerful way to search for newphysics and constrain the possible extensions.

Here, Hudsonet al [1] used cold polar moleculesto measure the electron EDM at the highest level ofprecision reported so far, providing a constraint onany possible new interactions. They obtainedde =(–2.4± 5.7stat ± 1.5syst)× 10−28e cm, wheree is thecharge on the electron, which sets a new upper limit of|de|< 10.5× 10−28e cm with 90 per cent confidence.This result, consistent with zero, indicates that theelectron is spherical at this improved level of preci-sion. The authors state that, ‘our measurement of atto-electronvolt energy shifts in a molecule probes newphysics at the tera-electronvolt energy scale’.

Reference

1. J. J. Hudson, D. M. Kara, I. J. Smallman, B. E. Sauer,M. R. Tarbutt and E. A. Hinds,Nature, 473 (7348),493–496 (2011) (26 May Issue).

Electrically Induced Ferromagnetism at RoomTemperature in Cobalt-Doped TitaniumDioxide

The electric field effect in ferromagnetic semiconduc-tors enables switching of the magnetization, whichis a key technology for spintronic applications. Here,Yamadaet al [1] demonstrated electric field–inducedferromagnetism at room temperature in a film of themagnetic oxide semiconductor, (Ti,Co)O2, by meansof electric double-layer gating with high-density elec-tron accumulation (>1014 per cm2). By applying agate voltage of a few volts, a low-carrier paramagneticstate was transformed into a high-carrier ferromagneticstate, thereby revealing the considerable role of elec-tron carriers in high-temperature ferromagnetism anddemonstrating a route to room-temperature semicon-ductor spintronics.

Reference

1. Y. Yamada, K. Ueno, T. Fukumura, H. T. Yuan,H. Shimotani, Y. Iwasa, L. Gu, S. Tsukimoto, Y. Ikuharaand M. Kawasaki,Science,332 (6033), 1065–1067(2011) (27 May Issue).


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Recent Books and Review Articlesin the Area of Materials Science, Engineering and Technology

(Contributed by the Editor)

Books• Energy and the Environment-Scientific and Tech-

nological Principles. Second Edition. By JamesA. Fay and Dan S. Golomb. Oxford UniversityPress, Oxford, 2011. Hardback. 384 pp., $89.95,£55. ISBN 9780199765133.

• Chemistry for Sustainable TechnologiesByNeil Winterton. RSC Publishing, Cambridge,2010. Hardback: 500 pp., illus. £62.99. ISBN9781847558138.

• Electronic Thin-Film Reliability By King-NingTu, Cambridge University Press, Cambridge,2010. Hardback: 412 pp., illus. $85, £55. ISBN9780521516136.

• Carbon Nanotubes for Polymer ReinforcementByPeng-Cheng Ma and Jang-Kyo Kim. CRC press,NY. 2011. Hard Cover. 224 pages. $179.95. ISBN:978-1-4398-2621-8.

• Biosensor NanomaterialsEdited by Li, Songjun /Singh, Jagdish / Li, He / Banerjee, Ipsita A. Wiley-VCH, Weinheim.2011. Hardcover. 278 pages. Euro119. ISBN-10: 3-527-32841-6. ISBN-13: 978-3-527-32841-3 - Wiley-VCH, Weinheim.

• Energy MaterialsEdited by Bruce, Duncan W. /Walton, Richard I. / O’Hare, Dermot. Wiley-VCH,Weinheim.2011. Hardcover. 304 pages. Euro 97.90.ISBN-10: 0-470-99752-4. ISBN-13: 978-0-470-99752-9 - John Wiley & Sons.

• Green Polymerization MethodsEdited by Math-ers, Robert T. / Meier, Michael A. R. Wiley-VCH,Weinheim.2011. Hardcover. 364 pages. Euro 139.ISBN-10: 3-527-32625-1. ISBN-13: 978-3-527-32625-9 - Wiley-VCH, Weinheim.

• Handbook of Stimuli-Responsive MaterialsEditedby Urban, Marek. Wiley-VCH, Weinheim.2011.Hardcover. 278 pages. Euro 119. ISBN-10: 3-527-32700-2. ISBN-13: 978-3-527-32700-3 - Wiley-VCH, Weinheim.



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• Twisted Photons- Applications of Light with OrbitalAngular Momentum. Edited by Torres, Juan P. /Torner, Lluis. Wiley-VCH, Weinheim.2011. Hard-cover. 244 pages. Euro 109. ISBN-10: 3-527-40907-6. ISBN-13: 978-3-527-40907-5 - Wiley-VCH,Berlin.

• Soap, Science, and Flat-Screen TVs A History ofLiquid CrystalsBy David Dunmur and Tim Sluckin.Oxford University Press, Oxford, 2010. 369 pp.$53.95. ISBN 9780199549405.For a review, see,Science, 331 (No. 6023),1388–1389 (2011).

• Bulletproof FeathersHow Science Uses Nature’sSecrets to Design Cutting-Edge Technology.Edited by Robert Allen. University of ChicagoPress, Chicago, 2010. 192 pp. $35, £22. ISBN9780226014708.For a review, see,Science,331 (No. 6023), 1389(2011).

• Carbon Nanotube and Graphene Device PhysicsByH.-S. Philip Wong and Deji Akinwande. CambridgeUniversity Press, Cambridge, 2010. Hardback: 261pp., illus. $85, £50. ISBN 9780521519052.

• Mathematical Methods for Optical Physics andEngineeringBy Gregory J. Gbur. Cambridge Uni-versity Press, Cambridge, 2011. Hardback: 818 pp.,illus. $90, £55. ISBN 9780521516105.

• The Quantum Story-A History in 40 Moments.By Jiim Baggott. Oxford University Press, Oxford,2011. Hardback: 489 pp. $29.95, £16.99. ISBN9780199566846.

• Nanoscale MOS Transistors-Semi-Classical Trans-port and Applications. By David Esseni, PierpaoloPalestri, and Luca Selmi. Cambridge University

Press, Cambridge, 2011. Hardback: 488 pp. $110,£65. ISBN 9780521516846.

• Switching to Solar–What We Can Learn from Ger-many’s Success in Harnessing Clean Energy. ByBob Johnstone. Prometheus, Amherst, NY, 2011.Paperback. 402 pages. $19. ISBN 9781616142223.

• Understanding Soft Condensed Matter via Mod-eling and ComputationEdited by Wenbing Huand An-Chang Shi. World Scientific, Hackensack,NJ, 2011 Hardback. 383 pages. $118, £73. ISBN9789814295581.

• Advanced Topics in Applied Mathematics–ForEngineering and the Physical Sciences. By Sud-hakar Nair. Cambridge University Press, Cam-bridge, 2011. Hardback: 232 pp., illus. $85; £55.ISBN 9781107006201.

• Generating Micro- and Nanopatterns on PolymericMaterials Edited by del Campo, Aranzazu / Arzt,Eduard. Wiley-VCH, Weinheim.2011. Hardcover.370 pages. Euro 139. ISBN-10: 3-527-32508-5.ISBN-13: 978-3-527-32508-5 - Wiley-VCH, Wein-heim.

• Microfluidic Reactors for Polymer ParticlesByKumacheva, Eugenia / Garstecki, Piotr. Wiley-VCH,Weinheim.2011. Hardcover. 236 pages. Euro 105.ISBN-10: 0-470-05773-4. ISBN-13: 978-0-470-05773-5 - John Wiley & Sons.


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p• Macrocycles -Construction, Chemistry and Nan-

otechnology Applications. By Higson, Seamus /Davis, Frank. Wiley-VCH, Weinheim.2011. Soft-cover. 608 pages. Euro 57.90. ISBN-10: 0-470-71463-8. ISBN-13: 978-0-470-71463-8 - JohnWiley & Sons.

• Concepts and Methods of 2D Infrared SpectroscopyBy Peter Hamm and Martin Zanni. Cambridge Uni-versity Press, Cambridge, 2011. Hardback: 296 pp.,$99, £60. ISBN 9781107000056.

• Foundation Mathematics for the Physical SciencesBy K. F. Riley and M. P. Hobson. Cambridge Uni-versity Press, Cambridge, 2011.Hardback: 735 pp., $80, £35. ISBN9780521192736.

• Foundation Mathematics for the Physical Sciences-Student Solution ManualBy K. F. Riley and M. P.

Hobson. Cambridge University Press, Cambridge,2011. Paperback: 222 pp., $19.95, £10.99. ISBN9780521141048.

• Optimization Concepts and Applications inEngineering By Ashok D. Belegundu andTirupathi R. Chandrupatla. 2nd ed. Cambridge Uni-versity Press, New York, 2011. Hardback. 477 pp.,$115, £65. ISBN 9780521878463.

• Principles of Physical MetallurgyBy AbhijitMallick. Viva Books, India. 2011. Paperback.Pages.528, Indian Rs. 595. ISBN 9788130914718.

• Bottled Lightning: Superbatteries, Electric Cars,and the New Lithium EconomyBy Seth Fletcher,Hill & Wang Publishers, 2011. 272 pp. $26, £18.99.ISBN: 780809030538.

For a review, see, B. Scrosati,Nature, 473, 448–449(26 May 2011).

MRS-S MembershipReaders are invited to become members of the Materials Research Society of Singapore (MRS-S).

Professional Membershipis open to any person engaged in activities associated with materials science, engineer-ing and technology.

Student Membership is open to any bonafide student of a tertiary institution genuinely interested in the practiceof materials science, engineering and technology.

Corporate Membership is open to any organisation, government or private, commercial or otherwise, that is inany way engaged in any activities that deal with any aspect ofmaterial science, engineering and technology. ACorporate Membership is entitled to nominate two of its employees as its official representatives and to change itsnominees from time to time provided the Committee has no objection to any such nomination.

Annual Subscription Fee:Professional Membership: S$50Student Membership: S$10Corporate Membership: S$500

For details and application form, please visit: www.mrs.org.sg



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Review Articles

• ε-Fe2O3 : An Advanced Nanomaterial ExhibitingGiant Coercive Field, Millimeter-Wave Ferromag-netic Resonance, and Magnetoelectric Coupling. ByJ. Tucek, R. Zboril, A. Namai and S.-I. Ohkoshi,Chem. Mater.,22 (24), 6483–6505 (2010).

AbstractNanosized iron oxides still attract significant atten-tion within the scientific community, because oftheir application-promising properties. Among them,ε-Fe2O3 constitutes a remarkable phase, taking pride ina giant coercive field at room temperature, significantferromagnetic resonance, and coupled magnetoelectricfeatures that are not observed in any other simple metaloxide phase.

In this article, the authors reviewed the basic struc-tural and magnetic characteristics of this extraordi-nary nanomaterial with an emphasis on questionableand unresolved issues raised during its intense researchin the past years. They show how a combination ofvarious experimental techniques brings essential andvaluable information, with regard to understandingthe physicochemical properties of theε-polymorph ofFe2O3, which remained unexplored for a long periodof time. In addition, thay recapitulate a series of syn-thetic routes that lead to the formation ofε-Fe2O3,highlighting their advantages and drawbacks, and alsodemonstrate how the magnetic properties ofε-Fe2O3

can be tuned through the exploitation of various mor-phologies ofε-Fe2O3 nanosystems, the alignment ofε-Fe2O3 nanoobjects in a supporting matrix, and var-ious degrees of cation substitution. Based on the cur-rent knowledge of the scientific community working inthe field of ε-Fe2O3, the authors finally arrive at twomain future challenges: (i) the search for optimal syn-thetic conditions to prepare single-phaseε-Fe2O3 witha high yield, desired size, morphology, and stability;and (ii) the search for a correct description of the mag-netic behavior ofε-Fe2O3 at temperatures below thecharacteristic magnetic ordering temperature. 104 Ref-erences.

• Synthesis of Environmentally Friendly CeramicMaterials via Solvothermal Reactions. By T. Sato,J. Ceram. Soc. Japan,118 (No. 1384), 1105–1114(2010).

AbstractSolvothermal reactions are designated as the reactionswhich use high temperatures and/or high pressure sol-vents. It is possible to control the acid–base reactionrate, morphology and agglomeration of the products,i.e., well dispersed nanoparticles with high crystallinitycan be obtained by solvothermal reactions. There-fore, solvothermal reactions are expected to be used togenerate environmentally friendly functional ceramicmaterials. Actually, various functional ceramics, suchas tetragonal zirconia, with excellent thermal stabil-ity and mechanical properties, visible light responsivephotocatalyst for environmental clean-up, high per-formance UV-shielding materials, etc. have been fab-ricated by solvothermal reactions. Unique plate-likeceria microparticles and the new Sn(II) titanate basedcompound which are impossible to be formed via anormal solid state reaction have also been formed.33 References.

• Oxides of Third Period Elements Revisited: Syn-thesis, Structure and Photoluminescence Propertiesof Silica, Magnesia, and Alumina. By T. Uchino,J. Ceram. Soc. Japan,118 (No. 1384), 1115–1123(2010).

AbstractSilica (SiO2), magnesia (MgO), and alumina (Al2O3)

are principal oxides composed of third period ele-ments. These oxides are prerequisite materials in thefield of ceramic science and technology but are notregarded as functional materials in their pure forms.

In recent publications, however, it has been demon-strated that these refractive oxides can exhibit efficientultraviolet/visible emissions by carefully controllingtheir microscopic structure and stoichiometry withoutadding any activator metals. Some intriguing prop-erties, such as white light emission, random lasing,photoinduced reversible interconversion of color cen-ters, have been achieved. The present approach willopen up new routes and new strategic issues to pro-duce highly functionalized materials consisting solelyof third period elements. 79 References.

• Thin Film Processing of MoO3 based Hybrid Mate-rials. By I. Matsubara,J. Ceram. Soc. Japan,118(No. 1384), 1124–1130 (2010).



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AbstractIntercalative inorganic–organic hybrids with usefulproperties have attracted much attention owing to theirpotential applications in various kinds of devices. Thedevelopment of thin film process is crucial to real-ize a novel device using the hybrid materials. Thinfilms of the intercalated organic/MoO3 hybrids havebeen prepared by an ex-situ intercalation process. Thehost MoO3 films were first deposited on substratesby using a CVD method followed by the interca-lation of organic components into the MoO3 films.The preparation of highlyb-axis oriented MoO3 filmsis essential to prepare the organic/MoO3 films. Theorganic/MoO3 films show semiconducting-like trans-port. The organic/MoO3 films show a distinct responseto VOCs (volatile organic compounds) by changingtheir electrical resistivity and exhibit higher sensitiv-ities to aldehyde gases, whereas almost no responseto toluene and xylene. The VOC sensing perfor-mance is closely related to the microstructure of theorganic/MoO3 thin films, which is able to be controlledby the growth conditions of the host MoO3 thin films.48 References.

• Anti-Reflecting and Photonic Nanostructures. ByS. Chattopadhyay, Y. F. Huang, Y. J. Jen,A. Ganguly, K. H. Chen, L. C. Chen,Mater Sci. &Engg. R.,69 (1–3), 1–35 (2010).

AbstractOptical reflection, or in other words the loss of reflec-tion, from a surface becomes increasingly crucial indetermining the extent of the light-matter interaction.The simplest example of using an anti-reflecting (AR)surface is possibly the solar cell that incorporatesan AR coating to harvest sunlight more effectively.Researchers have now found ways to mimic biologicalstructures, such as moth eyes or cicada wings, whichhave been used for the AR purpose by nature herself.These nanoscopic biomimetic structures lend valuableclues in fabricating and designing gradient refractiveindex materials that are efficient AR structures. Thereflectance from a selected sub-wavelength or gradi-ent index structures have come down to below 1% inthe visible region of the spectrum and efforts are on toachieve broader bands of such enhanced AR regime. In

addition to the challenge of broader bands, the perfor-mance of AR structures is also limited by factors suchas omni-directional properties and polarization of inci-dent light.

This review presents selected state-of-the-art ARtechniques, reported over the last half a century, andtheir guiding principles to predict a logical trend forfuture research in this field. 197 References.

• Polymers in Modern Ophthalmic Implants—Historical Background and Recent Advances.By D. Bozukova, C. Pagnoulle, R. Jerome andC. Jerome,Mater Sci. & Engg. R.,69 (6), 63–83(2010).

AbstractCataract surgery is the most frequently performedsurgical intervention, pursued by replacement of theopacified natural lens by a polymeric intraocular lens(IOL).

This review, based on an exhaustive number of sci-entific references, provides a brief simplified discus-sion of the surgical advances for cataract treatment,and is mainly focused on the process of IOL discov-ery, engineering and development. The performancesof the polymer materials, used for the IOLs fabricationare discussed in a comparative way, and their proper-ties, such as handling during surgery, biocompatibility,rate of some post-surgical complications (e.g. Poste-rior Capsular Opacification) and optical properties, areconsidered. Special attention is paid on the basic sci-entific approaches for engineering and modification ofthe IOL surface and bulk properties. Polymer coatingtechniques like ‘grafting onto’ and ‘grafting from’ arediscussed and exemplified by a variety of coating com-positions and performances.

In another part of the review, modification tech-niques concerning optimization of the bulk propertiesof the polymer lens are also discussed, and syntheticapproaches such as copolymerization and nanocom-posite formation are considered. A perspective aspectof this discussion concerns improvement of the per-formance of the main polymer by the incorporationof in situ formed or preformed nanoparticles. Themost attractive perspectives concerning the improve-ment of the IOL properties by chemical modificationapproaches are described. 226 References.



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• Carbon Spheres. By A. A. Deshmukh,S. D. Mhlanga and N. J. Coville,Mater Sci. & Engg.R.,70 (1–2), 1–28 (2010).

AbstractThe discovery of fullerenes has opened up new studiesin shaped carbon materials. In particular, the discov-ery that carbon atoms in fullerenes showed curved sp2

bonding also led to the discovery of single walled car-bon nanotubes and a re-investigation of carbon fibersand tubes. The area of shaped carbon materials hassince been dominated by studies of carbon nanotubes.The discovery has, however, also impacted on the wellknown spherical carbons exemplified by carbon blacks.Over the last two decades this has led to a resurgenceof interest in solid carbon spheres as well as core–shellspheres and hollow carbon spheres.

In this review, developments in the synthesis, dop-ing and functionalization of spherical carbon materials(but not fullerenes) are highlighted. The chemical andphysical properties as well as the uses of the carbonspheres are also described. 269 References.

• Ion Beam Doping of Semiconductor Nanowires. ByC. Ronning, C. Borschel, S. Geburt and R. Niepelt,Mater Sci. & Engg. R.,70 (3–6), 30–43 (2010).

AbstractThis review summarizes recent studies on ionimplantation doping of semiconductor nanowires anddiscusses both the advantages and disadvantages com-pared to other doping approaches in detail.

Furthermore, a guideline in both handling sam-ples and performing ion-beam doping experiments forthe nanosized objects and address the special needsof semiconductor nanowires in comparison to theirbulk counterparts, is presented. The confined geome-try leads to an enhanced sputtering yield, but also toan enhanced dynamic annealing effect; thus, a differ-ent structural impact of the ions, which can be evenused for an alignment of the nanowires. The removalof the implantation damage is a crucial prerequisite forsuccessful activation of implanted atoms and can beachieved via adequate annealing techniques, which aredescribed in this review. The authors also reported onseveral successful experiments in order to modify theelectrical and optical properties in a controlled manner

of silicon and compound semiconductor nanowires.119 References.

• Engineering the Properties of Metal Nanostruc-tures via Galvanic Replacement Reactions. ByC. M. Cobley and Y. Xia,Mater Sci. & Engg. R.,70(3–6), 44–62 (2010).

AbstractIn this review, the authors bring the reader up to datewith recent advances in the use of galvanic replacementreactions to engineer highly tunable nanostructures fora variety of applications.

They begin by discussing the variety of templatesthat have been used for such reactions and how thestructural details (e.g., shape, size, and defects, amongothers) have interesting effects on the ultimate product,beyond serving as a simple site for deposition. Thisis followed by a discussion of how one can manipu-late the processes of alloying and de-alloying to pro-duce novel structures and how the type of precursoraffects the final properties. Finally, the interesting opti-cal properties of these materials and some innovativeapplications in areas of biomedical engineering andcatalysis are discussed, completing the overview of thestate of the art in galvanic replacement. 130 Refer-ences.

• Controlled Growth and Modification of Vertically-Aligned Carbon Nanotubes for MultifunctionalApplications. By H. Chen, A. Roy, J.-B. Baek,L. Zhu, J. Qu and L. Dai,Mater Sci. & Engg. R.,70 (3–6), 63–91 (2010).

AbstractVertically-aligned carbon nanotubes (CNTs) possessmany advantages for a wide range of multifunctionalapplications. Along with the controlled growth ofaligned/micropatterned CNTs, surface modification ofvertically-aligned CNTs are essential in order to meetspecific requirements demanded for particular applica-tions. While many innovative synthetic methods havebeen developed for controlled growth of vertically-aligned multiwalled and single-walled CNTs, vari-ous interesting physical and chemical approaches have



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recently been devised for functionalization of the con-stituent carbon nanotubes in vertically-aligned CNT-arrays with their alignment being largely retained.

In this article, recent developments in the con-trolled growth and modification of vertically-alignedCNTs for multifunctional applications are reviewed.278 References.

• Boron Nitride Nanotubes. By C. Zhi, Y. Bando,C. Tang and D. Golberg,Mater Sci. & Engg. R.,70(3–6), 92–111 (2010).

AbstractThis article presents an overview of the up-to-datedevelopments in boron nitride nanotubes (BNNTs),including theory, fabrication, structure, physical prop-erties, chemical functionalization and applications.

Soon after the discovery of carbon nanotubes,BNNTs were theoretically predicted, followed by theirsuccessful fabrication by arc-discharge in 1995. Sub-sequently, various methods were developed for theBNNT synthesis, although till now, the growth ofhighly pure single-walled BNNTs in large quanti-ties remains a challenge. The physical property inves-tigations reveal that BNNTs’ exhibit a stable wideband gap, superb mechanical strength, high thermalconductivity, ultra-violet light emission, etc. All theseproperties build up the solid basis for their futuretechnological applications. Chemical modification isalso a decent approach to adjust the BNNTs proper-ties. In recent years the yield of multi-walled BNNTshas reached the grams level, that can allow theirdetailed chemical functionalization studies. So far,many kinds of functionalizations through differentweak interactions and covalent bonding were devel-oped. These treatments improved BNNT dispersionsin solvents and extended their fields of applications.Moreover, some application-related studies on multi-walled BNNTs, such as composites fabrication, hydro-gen storage, biocompatibility, and mechanical, andelectrical breakdown tests have also been started inrecent years. 402 References.

• Nucleation and Growth of Epitaxial Silicide in Sil-icon Nanowires. By Y.-C. Chou, K.-C. Lu andK. N. Tu, Mater Sci. & Engg. R.,70 (3–6), 112–125(2010).

AbstractTransition-metal silicides have been used in the sali-cide process to form gate and source/drain contactsin MOSFET devices. How to control silicide forma-tion in shallow junction devices and the kinetics ofsingle silicide phase formation between the Si andmetal thin films have received extensive attention andstudy. As the trend of miniaturization of Si devicesmoves from 45 nm to smaller sizes, the formation ofnanoscale metal silicides has attracted renewed interestin silicide formation. Nanostructures in Si nanowireshave been studied for basic components in electronicand optoelectronics devices, especially for biosensors.Well-defined nanoscale building blocks such as ohmiccontacts and gates on Si nanowires must be developedin order to be assembled into functional circuit compo-nents in future nanotechnology. It requires a systematicstudy of solid-state chemical reactions in the nanoscaleto form these circuit components.

In this review, the authors compare silicide forma-tion in thin films and in nanowires and focus on thenucleation and growth of epitaxial silicides. The dif-ference of silicide formation between the thin film caseand the nanowire case, especially the kinetics of nucle-ation and growth, is emphasized. 139 References.

• Magnetoresistance Oscillations in High-MobilityTwo-Dimensional Semiconductors: A unifieddescription with balance-equation model. ByX. L. Lei, Mater Sci. & Engg. R.,70 (3–6), 126–150(2010).

AbstractThis article gives a brief introduction to the magnetore-sistance oscillations in high-mobility two-dimensionalsemiconductors at low temperatures, which areinduced by a microwave radiation, a dc current, abranch of acoustic phonons, or a combination of them,and a comprehensive review of a balance-equationmodel for nonlinear magnetotransport in systems withshort thermalization time, which enables a unifieddescription for all these magnetoresistance oscilla-tions. 134 References.

• Trends in Semiconductor Defect Engineering at theNanoscale. By E. G. Seebauer and K. W. Noh,MaterSci. & Engg. R.,70 (3–6), 151–168 (2010).



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AbstractDefect engineering involves manipulating the type,concentration, spatial distribution, or mobility ofdefects within a crystalline solid. Defect engineering insemiconductors has become much more sophisticatedin recent years, driven by the need to control materialproperties at small length scales.

This article describes recent trends in defectengineering across several nano-oriented applications,beginning with Si-based integrated circuits and extend-ing into non-Si microelectronics and especially intooxide semiconductors for sensors and photocatalysis.Special focus fixes upon physical mechanisms thathave been little exploited up to now, but show sig-nificant promise as new means for controlling defectbehavior, including low-energy ion bombardment, sur-face chemistry, and photostimulation. Systems-basedmethods for parameter estimation offer considerablepromise for helping to understand the complex dif-fusion and reaction networks that characterize defectbehavior in most prospective applications. 266 Refer-ences.

• Formation and Structural Transition of Molecu-lar Self-Assembly on Solid Surface Investigatedby Scanning Tunneling Microscopy. By D. Wang,L. -J. Wan and C.-L. Bai,Mater Sci. & Engg. R.,70(3–6), 169–187 (2010).

AbstractThe spontaneous formation of ordered self-assemblyon solid supports is not only an intriguing subject forfundamental surface science study, but also closelyrelated to many emerging technologically importantapplications, especially in the field of nanotechnology.With the help of scanning tunneling microscopy (STM)at sub-molecular resolution, the detailed structuralinformation within the self-assembled monolayers canbe obtained, which allows us to have an insight intohow the interplay between the intermolecular weakinteractions and the substrate–molecule interactionsgoverns the formation of molecular self-assembly.

In this review, the structural transition of self-assembly in response to the subtle differences in themolecular structures and/or the environment change ispresented. The fundamental understanding about the

driving force controlling the assembly process pro-motes the development of various means to tune thestructural transition of supramolecular assembly onsolid surfaces and fabricate the sophisticated architec-tures. Finally, some future directions in the field areoutlined. 154 References.

• Cage Molecules for Self-Assembly. ByJ. N. Hohman, S. A. Claridge, M. Kim andP. S. Weiss,Mater Sci. & Engg. R.,70 (3–6),188–208 (2010).

AbstractSelf-assembled monolayers using functionalized cagemolecules offer distinct advantages because of theirsymmetry, lack of conformational flexibility, and well-defined chemistries. While these systems have notyet been studied to the extent that linear alkanethiolson Au1 1 1 have been studied, early explorationsindicate great promise and important differences. Forsimple cage molecules that bind upright on the sub-strate, tilt domain boundaries found in linear chain sys-tems are completely eliminated. Cage molecules canbe designed to have a great range of intermolecularinteractions, which thereby define the stabilities ofthe assemblies. Weakly interacting monolayers, suchas those of 1-adamantanethiol on Au1 1 1 arelabile relative to exchange reactions from solution,vapor, or contact, and thus can be used as sacrificialplaceholders and diffusion barriers in soft lithography.Such molecules can be further functionalized to serveas molecular resists for chemical patterning. Cagemolecules can also be designed with directional inter-actions, as for carboranethiols, where molecules withidentical lattices have dramatically different chemicaland physical properties, and film stabilities. Multifunc-tional cage molecules enable further directed surfacereactions, higher order supramolecular assembly, andultimately, precise three-dimensional assembly off thesurface. 323 References.

• Principles and Applications of Micro and NanoscaleWrinkles. By Y. Mei, S. Kiravittaya, S. Harazim andO. G. Schmidt,Mater Sci. & Engg. R.,70 (3–6),209–224 (2010).



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AbstractIn this review, the authors summarize recent andinteresting applications of micro and nanoscale wrin-kles. Fluidic studies are comprehensively highlightedfor various wrinkled nanochannels. Wrinkling as amechanical characterization tool is also explained. Asa new feature, wrinkles are employed to modify struc-tures or physical properties of nanomaterials. It ispromising to apply wrinkling for strain-engineering ofgraphene.

The authors believe that wrinkling offers entirelynew research perspectives in micro and nanotech-nologies as well as in material sciences andengineering. 75 References.

• Fabrication, Biological Effects, and Medical Appli-cations of Calcium Phosphate Nanoceramics. ByY. Hong, H. Fan, B. Li, B. Guo, M. Liu andX. Zhang,Mater Sci. & Engg. R.,70(3–6), 225–242(2010).

AbstractDue to large grain sizes, the biological properties ofthe conventional calcium phosphate (Ca–P) bioceram-ics are limited to a great extent. Progresses in nano-technological approaches now allow the fabrication ofnanocrystalline Ca–P bioceramics.

In this article the authors first review currentmethodologies of the Ca–P nanocrystal syntheses andnanoceramic processes. In particular, they emphasizein this article the fabrication of porous Ca–P nanoce-ramics using a modified co-precipitation synthesis andits microwave sintering. Subsequently, the biologi-cal properties of the three-dimensional porous Ca–Pnanoceramics, involving protein adsorption, cell adhe-sion, bone repair, osteoconductivity and osteoinduc-tivity, are introduced in detail on the basis of thein vitro protein adsorption and cell adhesion, andin vivo intramuscular and bone implant experiments.Because of high specific surface area, nano-level sur-face topography, high surface defects and interconnect-ing macropores with abundant micropores, the Ca–Pnanoceramics can well initiate and regulate a cascadeof gene activities of cells, thereby resulting in higherin vivo osteoconductivity and osteoinductivity than theconventional ones. Finally, the degradability, poten-tial risk, and anticancer activity of the nanoceramics

are discussed. In summary, because of the chemicaland macro-/nanoscale structural similarities with bone,the Ca–P nanoceramics are hopeful of becoming anew generation of biomaterials for hard tissue repair.195 References.

• Order and Disorder in the Heteroepitaxy of Semi-conductor Nanostructures. By F. Ratto and F. Rosei,Mater Sci. & Engg. R.,70 (3–6), 243–264 (2010).

AbstractThe heteroepitaxy of semiconductor pairs with a smalllattice mismatch is a process of tremendous interest inmaterials science and technology. Epitaxial nanostruc-tures are proposed as the building blocks of a varietyof innovative applications. An ample variety of natural(bottom–up, parallel) and artificial (typically integratedtop–down and bottom–up, sequential and/or parallel)methods have been reported to yield some extent ofcontrol over nanostructure positioning.

This review aims at highlighting some of the mostrelevant concepts developed over recent years. Whilea significant number of reviews on different aspects ofthe synthesis and characterization of individual nanos-tructures are found in the literature, the complexity ofthe issues mentioned above has never been addressedwithin a dedicated framework so far. 263 References.

• Nanoparticle-based Environmental Sensors. ByL. Wang, W. Ma, L. Xu, W. Chen, Y. Zhu, C. Xuand N. A. Kotov,Mater Sci. & Engg. R.,70 (3–6),265–274 (2010).

AbstractEnvironmental monitoring requires rapid and reliableanalytical tools that can perform sample analysis withminimal sample handling. Nanoparticle (NP)-basedenvironmental sensors have the potential to detect tox-ins, heavy metals, and organic pollutants in air, water,and soil, and are expected to play an increasinglyimportant role in environmental monitoring. They canboth improve detection and sensing of pollutants, andbe used to develop new remediation technologies.Compared to traditional detection methods, NP sen-sors may have higher selectivity, sensitivity and stabil-ity and lower cost.



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This review reports on the development of sens-ing principles based on NP, including synthesis of spe-cific NP components, optical sensors, electrochemicalbiosensors and magnetic-relaxation sensors. Advan-tages over other environmental monitoring methods arediscussed. 180 References.

• Surface Nano-Functionalization of Biomaterials. ByX. Liu, P. K. Chu and C. Ding,Mater Sci. & Engg.R.,70 (3–6), 275–302 (2010).

AbstractAfter biomaterials are implanted into the human body,there are inevitable interactions between the biolog-ical environment and implant surfaces. Therefore,the surface of biomaterials has become one of thehottest research topics. Nanotechnology is a pow-erful tool in modern materials science and able toincorporate biomimicry on the nanoscale into mate-rials engineering. Therefore, research on nanotech-nology/nanostructured biomaterials has attracted muchattention. A nano-functionalized surface has promisingbiological properties and clinical applications of bio-materials can be improved by producing a nanostruc-tured surface.

Many surface modification techniques have beenadopted to produce nano-functionalized biomaterialssurface, and in this paper, the fabrication, characteriza-tion, and properties of biomaterials such as ceramics,metals, and polymers with nanostructured surfaces arereviewed. 183 References.

• In Situ TEM Investigation of Dynamical Changes ofNanostructures. By L. J. Chen and W. W. Wu,MaterSci. & Engg. R.,70 (3–6), 303–319 (2010).

AbstractIn situ investigation of the temperature induced phasetransformation, structural and chemical evolution ofnanocrystals is important for understanding the struc-ture and stability of nanomaterials. Transmission elec-tron microscopy (TEM), one of the most powerful toolsfor characterizing nanostructured materials, is essentialfor the development of nanotechnology. In situ TEM isa technique that allows a direct observation of dynamicproperties in nanoscale. Recent development of ultra-high vacuum TEM (UHV-TEM) further enables the

investigation on atomic-scale materials systems in aclean environment. The appropriate utilization of theUHV-TEM will be beneficial in studying the funda-mental mechanisms of dynamic reactions, formationof transient phase, solid-state amorphization, epitaxialgrowth, growth kinetics and evolution of defects.

In this review, the authors present the most recentprogress in observing dynamic processes in nanoscaleby in situ UHV-TEM. 84 References.

• Lateral Nanowire/Nanobelt based Nanogenera-tors, Piezotronics and Piezo-Phototronics. ByZ. L. Wang, R. Yang, J. Zhou, Y. Qin, C. Xu, Y. Huand S. Xu,Mater Sci. & Engg. R.,70(3–6), 320–329(2010).

AbstractRelying on the piezopotential created in ZnO understraining, nanogenerators, piezotronics and piezo-phototronics developed based on laterally bondednanowires on a polymer substrate have been reviewed.

The principle of the nanogenerator is a tran-sient flow of electrons in external load as drivenby the piezopotential created by dynamic straining.By integrating the contribution made by millionsof nanowires, the output voltage has been raisedto 1.2 V. Consequently, self-powered nanodeviceshave been demonstrated. Alternatively, the piezopo-tential can act as a gate voltage that can tune/gatethe transport process of the charge carriers in thenanowire, which is a gate-electrode free field effecttransistor (FET). The device fabricated based onthis principle is called the piezotronic device. Piezo-phototronic effect is about the tuning and controllingof electro-optical processes by strain induced piezopo-tential. The piezotronic, piezophotonic and pieozo-phototronic devices are focused on low frequencyapplications in areas involving mechanical actions,such as MEMS/NEMS, nanorobotics, sensors, actua-tors and triggers. 48 References.

• Nanostructured Photon Management for High Per-formance Solar Cells. By J. Zhu, Z. Yu, S. Fan andY. Cui, Mater Sci. & Engg. R.,70 (3–6), 330–340(2010).



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AbstractAdvanced photon management, involving both absorp-tion enhancement and reflection reduction, is criticalto all photovoltaic devices. Here the authors discuss anovel solar cell structure with an efficient photon man-agement design.

The centerpiece of the design is the nanocone struc-ture, which is fabricated by a scalable low temper-ature process. With this design, devices with a verythin active layer can achieve near perfect absorptionbecause of both efficient anti-reflection and absorptionenhancement over a broadband of spectra and a widerange of angles of incidence. The device performanceof this design is significantly superior to that of conven-tional devices. More excitingly, the design and processis, in principle, not limited to any specific materials;hence, it opens up exciting opportunities for a varietyof photovoltaic devices to further improve the perfor-mance, reduce materials usage, and relieve the abun-dance limitation. 34 References.

• Fabrication and Electrical Properties of GrapheneNanoribbons. By J. Bai and Y. Huang, Mater Sci.& Engg. R.,70 (3–6), 341–353 (2010).

AbstractGraphene is a semimetal with a zero band gap, andtherefore cannot be used for effective field-effecttransistors (FETs) at room temperature. Theoreticalstudy predicted an appreciable band gap opening withthe formation of nanometer graphene nanoribbons(GNRs), providing opportunities for graphene basedtransistor application.

In this paper, the authors review recentdevelopments in fabrication and electrical prop-erty studies of GNRs. They first study the theoreticprediction of electrical structures in ideal graphenenanoribbons which is closely related to the edge con-figurations. Different experimental efforts to fabri-cate GNRs are introduced and the electrical transportbehaviors of fabricated GNR device are described. Theauthors then investigate the effect of edge disorder andcharge impurities on real device performance, in whichAnderson localization and Coulomb blockade effectare discussed to explain the observed transport behav-iors. Other approaches such as symmetry broken to

induce band gap on bulk graphene are also described.138 References.

• Graphene–Dielectric Integration for Graphene Tran-sistors. By L. Liao and X. Duan,Mater Sci. & Engg.R.,70 (3–6), 354–370 (2010).

AbstractGraphene is emerging as an interesting electronicmaterial for future electronics due to its exception-ally high carrier mobility and single-atomic thickness.Graphene–dielectric integration is of critical impor-tance for the development of graphene transistorsand a new generation of graphene based electronics.Deposition of dielectric materials onto graphene isof significant challenge due to the intrinsic materialincompatibility between pristine graphene and dielec-tric oxide materials.

Here, the authors review various strategies beingresearched for graphene–dielectric integration. A phys-ical assembly approach has recently been explored tointegrate dielectric nanostructures with graphene with-out introducing any appreciable defects, and enabledtop-gated graphene transistors with the highest carriermobility reported to date. They conclude with a briefsummary and perspective on future opportunities. 100References.

• Phosphors in Phosphor-Converted White Light-Emitting Diodes: Recent Advances in Materials,Techniques and Properties. By S. Ye, F. Xiao,Y. X. Pan, Y. Y. Ma and Q. Y. Zhang,Mater Sci. &Engg. R.,71 (1), 1–34 (2010).

AbstractPhosphor-converted white light-emitting diodes(pc-WLEDs) are emerging as an indispensablesolid-state light source for the next generation light-ing industry and display systems due to their uniqueproperties including but not limited to energy savings,environment-friendliness, small volume, and long per-sistence. Until now, major challenges in pc-WLEDshave been to achieve high luminous efficacy, high chro-matic stability, brilliant color-rending properties, andprice competitiveness against fluorescent lamps, whichrely critically on the phosphor properties. A compre-hensive understanding of the nature and limitations



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of phosphors and the factors dominating the generaltrends in pc-WLEDs is of fundamental importance foradvancing technological applications.

This review aims to provide the most recentadvances in the synthesis and application of phos-phors for pc-WLEDs with emphasis specifically on:(a) principles to tune the excitation and emission spec-tra of phosphors: prediction according to crystal fieldtheory, and structural chemistry characteristics (e.g.,covalence of chemical bonds, electronegativity, andpolarization effects of element); (b) pc-WLEDs withphosphors excited by blue-LED chips: phosphor char-acteristics, structure, and activated ions (i.e. Ce3+

and Eu2+), including YAG: Ce, other garnets, non-garnets, sulfides, and (oxy)nitrides; (c) pc-WLEDswith phosphors excited by near ultraviolet LED chips:single-phased white-emitting phosphors (e.g., Eu2+–Mn2+ activated phosphors), red-green-blue phosphors,energy transfer, and mechanisms involved; and (d) newclues for designing novel high-performance phosphorsfor pc-WLEDs based on available LED chips. Empha-sis shall also be placed on the relationships amongcrystal structure, luminescence properties, and deviceperformances. In addition, applications, challenges andfuture advances of pc-WLEDs are discussed. 377 Ref-erences.

• Single-Walled Carbon Nanotubes in BiomedicalImaging. By Z. Liu, K. Yang and S.-T. Lee,J. Mater.Chem.,21 (3), 586–598 (2011).

AbstractThis article reviews the latest developments in usingsingle-walled carbon nanotubes (SWNTs) for biomed-ical imaging. SWNTs with a number of unique intrin-sic optical properties have been widely used as contrastagents in Raman imaging, near-infrared (NIR) fluores-cence imaging and photoacoustic imagingin vitro andin vivo.

More imaging functionalities including positronemission tomography (PET) and magnetic resonance(MR) imaging can be achieved by either utilizing exter-nal labels or the metal impurities of nanotube samples.Although there is still a long way to go before SWNTsare ready for clinical use, they are promising nanoma-terials with great potential in multimodality biomedicalimaging. 111 References.

• ZnO based Advanced Functional Nanostruc-tures: Synthesis, Properties and Applications. ByM. Ahmad and J. Zhu,J. Mater. Chem.,21 (3),599–614 (2011).

AbstractZnO nanostructures, due to their novel properties, arepromising components in a wide range of nanoscaledevices for future applications. This article provides acomprehensive review of the current research activitiesthat focus on the synthesis, characterization and appli-cations of ZnO based nanostructures.

The most commonly applied methodologies for thesynthesis of ZnO nanostructures are briefly described.A range of remarkable characteristics is then presented,organized into sections describing the optical, electri-cal and mechanical properties. Finally, a brief analysisof the possible future trends for the application of thisinteresting semiconductor oxide for hydrogen storageand biosensors, are included. These studies constitutethe basis for developing versatile applications of ZnOnanostructures. 244 References.

• Recent Developments in Fabrication and Appli-cations of Colloid based Composite Particles. ByM. Agrawal, S. Gupta and M. Stamm,J. Mater.Chem.,21 (3), 615–627 (2011).

AbstractIn recent years, a variety of nano-(micro) scaleorganic–inorganic composite particles with welldefined chemical composition, size and morphologyhave been fabricated and their applications in widespectrum of cutting-edge technological areas havebeen explored.

This review is focused on recent developmentstowards various fabrication methodologies and appli-cations of such colloid based composite particles.Strategies for preparation of nano and micro scale com-posite materials are presented by choosing as exampleshard core based composite particles having core–shelland raspberry-like morphologies and soft core basedcomposite microgels. Applications of these materialsin wide range of potential areas are discussed includ-ing the fabrication of colloidal crystal arrays, hollowspheres, superhydrophobic surfaces, filler carriers andsmart nanomaterials. 102 References.



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• Graphene: Learning from Carbon Nanotubes. ByL. Huang, B. Wu, G. Yu and Y. Liu,J. Mater. Chem.,21 (4), 919–929 (2011).

AbstractAs a new member of the carbon family, graphene hasmany fascinating properties and potential applicationswith the greatest degree of similarity to its “brother”carbon nanotubes (CNTs). Research on graphene hasdeveloped rapidly in the past 6 years, partially due to itssimilarity to carbon nanotubes, which have been exten-sively studied for almost two decades.

The adaptation of CNT research strategies for thedevelopment of graphene preparation, functionaliza-tion and applications as well as the conversion andhybrid structures of carbon nanotubes and graphene arereviewed in this article. 108 References.

• Organic–Inorganic Hybrid Aerogels with HighMechanical Properties via Organotrialkoxysilane-Derived Sol–Gel Process. By K. Kanamori,J. Ceram. Soc. Japan,119 (No. 1385), 16–22(2011).

AbstractA brief overview of siloxane-based low-density aero-gels and aerogels-like xerogels is presented. Aero-gels are highly porous solids composed of inorganicoxides, metals, cross-linked polymers and carbons, andare known to possess a number of excellent physi-cal properties such as high visible-light transparencywith low refractive index, low dielectric properties,and extremely-low thermal conductivity. Aerogels aretherefore regarded as a promising candidate for appli-cations such as superinsulators; however, a massproduction and applications of aerogels have been sig-nificantly discouraged due to the lack of mechanicalproperties since the first invention in 1931.

This review introduces the substantial effort toimprove the mechanical properties of aerogels withparticularly highlighting the recent findings on elasticorganic–inorganic hybrid aerogel monoliths obtainedfrom methyltrimethoxysilane (MTMS) using the con-trolled sol–gel chemistry. 79 References.

• Recent Trends in Shape Forming from Col-loidal Processing: A Review. By C. Tallon and

G. V. Franks,J. Ceram. Soc. Japan,119(No. 1387),147–160 (2011).

AbstractShaping ceramic materials is a research area which hascontinuing innovation and excellence. Dry processingroutes gave way to colloidal techniques enabling thepreparation of more complex shapes for a wide andgrowing field of applications. Both dense and porousceramics with improved properties can be produced.The development of colloidal processing led to thecreation of the near-net-shaping concept, performedthrough slip-casting, gel-casting and freeze-casting.Even though these concepts have been used for the lastfew decades, different trends and combinations of thesetechniques are refreshing the processing strategies inrecent years. New chemistries and concepts continueto emerge.

This paper is an overview of the recent trends innear-net-shaping routes, having a deeper look into gel-casting and freeze- casting, since both processes areused in the preparation of tailored and custom denseand porous ceramics. 102 References.

• Silicon Carbide Powder and Sintered Materials. ByH. Tanaka,J. Ceram. Soc. Japan,119 (No. 1387),218–233 (2011).

AbstractSilicon carbide (SiC) was first industrially synthesizedin 1894 and has been used as refractories, abrasives andhigh temperature furnace parts. The basic fabricationand sintering technologies were almost established byabout 1970. Recently, sintered SiC has become a keymaterial as it has been widely used in advanced indus-tries of semiconductors and high precision machines.New fabrication methods for modern SiC powders andsintering methods are being developed on the bases oftraditional methods.

In this review, the original studies and recent devel-opments have been given maximum possible emphasis,and in particular, basic points of view are introduced.169 References.

• Study of the Friction, Adhesion and Mechani-cal Properties of Single Crystals, Ceramics andCeramic Coatings by AFM. By J. J. Roa, G. Oncins,



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J. Dıaz, X. G. Capdevila, F. Sanz and M. Segarra,J. Europ. Ceram. Soc.,31 (4), 429–449 (2011).

AbstractThis paper reviews commonly used methods ofanalyzing and interpreting friction, adhesion andnanoindentation with an AFM tip test data, with aparticular emphasis of the testing of single crystals,metals, ceramics and ceramic coatings. Experimentalresults are reported on the friction, mechanical andadhesion properties of these materials.

The popularity of AFM testing is evidenced by thelarge quantity of papers that report such measurementsin the last decade. Unfortunately, a lot of informa-tion about these topics is scare in the literature. Thispaper is aimed to present the basic physical modellingemployed and also some examples using each tech-nique. 205 References.

• Crystal Chemistry of the Monazite Structure. ByN. Clavier, R. Podor and N. Dacheux,J. Europ.Ceram. Soc.,31 (6) 941–976 (2011).

AbstractThe AXO4 monazite-type compounds form anextended family that is described in this review in termsof field of stability versus composition. All the sub-stitution possibilities on the cationic and anionic sitesleading to the monazite structure are reported. Thephosphate, vanadate, chromate, arsenate, sulphate andsilicate families are described and the unit-cell param-eters of pure compounds and solid solutions are gath-ered. The stability limits of the monazite-type structureare discussed versus several models generally corre-lated with geometric criteria. The effects of physico-chemical parameters such as pressure, temperature andirradiation on the monazite-type structure stability arealso discussed. The structural relationships betweenthe monazite structure and the related structures (zir-con, anhydrite, barite, AgMnO4, scheelite and mono-clinic BiPO4, CaSeO3, rhabdophane and SrNp(PO4)2)are described. 398 References.

• Polymer and Organic Nonvolatile Memory Devices.By P. Heremans, G. H. Gelinck, R. Muller,K.-J. Baeg, D.-Y. Kim and Y.-Y. Noh,Chem. Mater.,23 (3), 341–358 (2011).

AbstractOrganic molecules and semiconductors have been pro-posed as active part of a large variety of nonvolatilememory devices, including resistors, diodes and tran-sistors. In this review, the authors focus on elec-trically reprogrammable nonvolatile memories. Theyclassify several possible devices according to theiroperation principle and critically review the role of theπ-conjugated materials in the device operation. Theyalso propose specifications for applications for organicnonvolatile memory, and review the state of the art withrespect to these target specifications. Conclusions aredrawn regarding further work on materials and devicearchitectures. 129 References.

• Design of Organic Semiconductors from MolecularElectrostatics. By G. Heimel, I. Salzmann, S. Duhmand N. Koch,Chem. Mater., 23(3), 359–377 (2011).

AbstractProgress in the field of organic electronics depends onthe synthesis of newπ-conjugated molecules to fur-ther improve the performance of, for example, organiclight-emitting diodes, organic photovoltaic cells, andorganic field-effect transistors. However, the interrela-tion between the properties of isolated molecules onone hand and close-packed thin films on the other handis far from trivial.

Here, the authors review recent progress in theunderstanding of electrostatic phenomena, which orig-inate in the collective action of the anisotropic chargedistribution in typical conjugated molecules. Both theπ-electron systems and polar end-group substitutionsexposed at the surface of a molecular or polymeric filmare seen to form dipole layers, which critically impactthe device-relevant ionization energy and electronaffinity of that film. After briefly revisiting electrostaticfundamentals and critically assessing related experi-mental methods, the energies of the frontier electronicstates in organic thin films are shown to depend appre-ciably on the orientation of the constituent moleculeswith respect to device-relevant interfaces. For filmsof preferentially “standing” or “edge-on” molecules,this opens the possibility for electronic-structure engi-neering with intra-molecular polar bonds. On the basisof these findings, additional insights into the workingprinciples of organic electronic devices are provided



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and valuable guidelines for the synthesis of improvedorganic semiconductors are derived. 220 References.

• Discotic Liquid Crystals for Opto-Electronic Appli-cations. By B. R. Kaafarani,Chem. Mater., 23 (3),378–396 (2011).

AbstractDiscotic liquid crystals (DLCs) have been exploited inopto-electronic devices for their advantageous proper-ties including long-range self-assembling, self-healing,ease of processing, solubility in a variety of organicsolvents, and high charge-carrier mobilities along thestacking axis.

An overview of DLCs and their charge-carriermobilities, theoretical modeling, alignment, and deviceapplications is addressed herein. The effects of align-ment on charge-carrier properties of DLCs are dis-cussed. Particular attention is devoted to processingtechniques that achieve suitable alignment of DLCsfor efficient electronic devices such as zone-casting,zone melting, Langmuir-Blodgett deposition, solution-casting on preoriented polytetrafluoroethylene (PTFE),surface treatment, IR irradiation, application of a mag-netic field, use of sacrificial layers, use of blends, appli-cation of an electric field, and others. 223 References.

• Navigating the Color Palette of Solution-Processable Electrochromic Polymers. ByC. M. Amb, A. L. Dyer and J. R. Reynolds,Chem.Mater., 23 (3), 397–415 (2011).

AbstractSolution-processable electrochromic (EC) polymersthat can be switched from one distinct color stateto a highly transmissive and near colorless state arerequired for applications in both EC windows and dis-plays.

Using a tour around the color wheel, the authorsdescribe the various EC polymer (ECP) compositionsthat now make a full palette of colors available demon-strating a set of structure- property relationships.Electrochemical and electrochromic characterizationmethodologies are described and their application toECPs demonstrated. Processing and patterning meth-ods including spray casting, screen-, flexo-, and ink

jet printing, along with photo- and soft lithogra-phy are described. Absorptive/transmissive (windowtype) and absorptive/reflective (display type) devicesare described as platforms for practical applications.131 References.

• Photoconducting Polymers for Photorefrac-tive 3D Display Applications. By J. Thomas,C. W. Christenson, P.-A. Blanche, M. Yamamoto,R. A. Norwood and N. Peyghambarian,Chem.Mater., 23 (3), 416–429 (2011).

AbstractPhotorefractive composites derived from photocon-ducting polymers offer the advantage of dynamicallyrecording holograms without the need for processingof any kind. Thus, they are the material of choice formany cutting edge applications, such as updatable 3Ddisplays and imaging through a scattering medium.

This article reviews the basic properties ofphotorefractive polymer systems and the inherentadvantages that have attracted much attention. Thechemistry and physics relevant for the design of thehigh-performance guest-host composite are discussedand recent advances emphasized. In particular, a chargetransporting polymer with high mobility and history-independent response times is highlighted, as well aspolymer systems useful for holographic displays andthe material considerations necessary to develop high-speed, large-sensitivity composites. 115 References.

• Systematic Nanoengineering of Soft MatterOrganic Electro-optic Materials. By L. R. Dalton,S. J. Benight, L. E. Johnson, D. B Knorr, Jr.,I. Kosilkin, B. E. Eichinger, B. H. Robinson,A. K.-Y. Jen and R. M. Overney,Chem. Mater., 23(3), 430–445 (2011).

AbstractAn overview of the development and utilizationof organic electro-optic materials is presented withemphasis on the role played by quantum and statis-tical mechanical calculations in understanding criti-cal structure/function relationships that have guidedthe improvement of such materials over the past twodecades.



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This review concentrates largely on three classesof organic electro-optic materials prepared by electricfield poling of materials near their glass transitiontemperature: (1) chromophore/polymer compos-ite materials, (2) dendrimers and polymers con-taining covalently incorporated chromophores, and(3) matrix-assisted-poling (MAP) materials where spe-cific spatially anisotropic interactions enhance pol-ing efficiency. In particular, the role of chromophoreshape, restrictions on chromophore motion associatedwith covalent bonds, and lattice dimensionality effectsare reviewed. The role of device design and auxiliaryproperties (optical loss, thermal stability, photochem-ical stability, processability) in influencing the utiliza-tion of organic electro-optic materials is also brieflyreviewed. 146 References.

• Halogenated Materials as Organic Semiconductors.By M. L. Tang and Z. Bao,Chem. Mater., 23 (3),446–455 (2011).

AbstractOrganic semiconductors have great potential as theactive material in low-cost, large area plastic elec-tronics, whether as light-emitting diodes (LEDs),field-effect transistors (FETs) or solar cells. Organicsemiconducting materials retain the processabilityassociated with polymers while maintaining goodoptoelectronic properties, for example, high absorp-tion coefficients for photons in the visible region, andfield-effect mobilities comparable with that of amor-phous silicon. The elucidation of important structure-property relationships is vital for the design offunctional, high-performance organic semiconductors.

In this review, the authors summarize such rela-tionships stemming from the halogenation of organicsemiconductors. While it has been known in the pastdecade that fluorination lowers the energy levels incarbon based systems, induces stability and electrontransport, less is known about the effect of the otherhalogens. Chlorination has recently been shown to bea viable route ton-type materials. The bandgap of con-jugated compounds can also be decreased slightly bythe addition of Cl, Br, and I to the aromatic core. Theeffect of the halogenated moieties on the packing ofmolecules is discussed. 80 References.

• Processable Low-Bandgap Polymers for Photo-voltaic Applications. By P. -L. T. Boudreault,A. Najari and M. Leclerc,Chem. Mater., 23 (3),456–469 (2011).

AbstractOver the last five years, organic photovoltaic deviceshave emerged as a new competitor to silicon-basedsolar cells. In particular, the bulk heterojunction archi-tecture (BHJ), in which the photoactive layer consistsof a bicontinuous blend of an electron donor and anelectron acceptor, has allowed power conversion effi-ciencies around 8%.

The latest conjugated polymers used insuch BHJ solar cells are presented in thisreview, mainly focusing on electron-donating(p-type) polymers based on thiophenes, 1,3,2-benzodiathiazoles, pyrrolo[3,4-c]pyrrole-1,4-diones,benzo[1,2-b; 3,4-b]dithiophenes, and few other mate-rials with more exotic structures. This review shouldbe helpful to evaluate which are the most promisingmaterials and where this research field is going in theyears to come. 106 References.

• Molecule Solution-Processed Bulk Heterojunc-tion Solar Cells. By B. Walker, C. Kim andT.-Q. Nguyen, Chem. Mater., 23 (3), 470–482(2011).

AbstractAlthough most research in the field of organic bulkheterojunction solar cells has focused on combina-tions of a p-type conducting polymer as a donor anda fullerene-based acceptor, recent work has demon-strated the viability of solution-processed heterojunc-tions composed entirely of molecular solids. Molecularsolids offer potential advantages over conjugated poly-mer systems in terms of easier purification, amenabil-ity to mass-scale production and better batch-to-batchreproducibility.

This article reviews the major classes of moleculardonors that have been reported in the literature in thepast several years and highlights some of key consider-ations in molecular heterojunction design compared topolymer-based bulk heterojunctions. 96 References.



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• Metal-Ion-Responsive Fluorescent Probes for Two-Photon Excitation Microscopy. By S. Sumalekshmyand C. J. Fahrni,Chem. Mater., 23 (3), 483–500(2011).

AbstractMetal-ion-responsive fluorescent probes are powerfultools for visualizing labile metal ion pools in livecells. To take full advantage of the benefits offered bytwo-photon excitation microscopy, including increaseddepth penetration, reduced phototoxicity, and intrin-sic 3D capabilities, the photophysical properties of theprobes must be optimized for nonlinear excitation.

This review summarizes the challenges associatedwith the design of two-photon excitable fluorescentprobes and labels, and offers an overview of recentefforts in developing selective and sensitive reagentsfor the detection of metal ions in biological systems.114 References.

• Recent Advances in Conjugated Polyelectrolytesfor Emerging Optoelectronic Applications. ByA. Duarte, K.-Y. Pu, B. Liu and G. C. Bazan,Chem.Mater., 23 (3), 501–515 (2011).

AbstractThis review summarizes recent advances in the sci-ence and applications of conjugated polyelectrolytes(CPEs), with an emphasis on direct visual sensing,cellular imaging, and the fabrication of optoelectronicdevices.

CPEs backbones that incorporate donor- accep-tor units are useful for direct visual sensing, whereasCPEs with hyperbranched structures, or biocompati-ble long side chains, are particularly useful for cel-lular imaging. With specially designed counterions,CPEs also demonstrate unique function in device fab-rication and operation, for example, in dye-sensitizedsolar cells (DSSCs), bulk heterojunction (BHJ) solarcells, polymer light-emitting diodes (PLEDs), poly-mer light-emitting electrochemical cells (PLECs), andorganic thin film transistors (OFET). Additionally, newstrategies to modify and optimize CPE properties forspecific applications are provided. The work summa-rized herein not only illustrates relationships betweenmolecular structures and function, but also highlightshow the structural versatility of CPEs makes them a

unique category of multifunctional materials with thepotential for fulfilling a variety of optical and elec-tronic applications in solution, mixed media, and in thesolid state. 90 References.

• Magneto-Optic Properties of RegioregularPolyalkylthiophenes. By P. Gangopadhyay,G. Koeckelberghs and A. Persoons,Chem. Mater.,23 (3), 516–521 (2011).

AbstractThis paper reviews work on the magneto-optical prop-erties ofπ-conjugated polymers, in particular regioreg-ular poly(3-alkyl) thiophenes. The authors give anoverview of the theoretical formalism that led tothe first observation of Faraday rotation from thinfilms of poly(3-dodecyl) thiophene and experimentalresults, which include Faraday rotation studies fromthin films composed of various polythiophene deriva-tives with varying degree of regioregularity They alsodiscuss possible correlations of Faraday rotation andthe supramolecular organization within the thin filmsof these polymers. When appropriate, the authorspoint out possible applications or suggest directionsfor further research. Organic magneto-optic polymermaterials could reduce production costs for variousmagneto-optic devices, as these materials are solutionprocessable and amenable to roll-to-roll processing.39 References.

• Application of Molecular Simulation Techniques tothe Study of Factors Affecting the Thin-Film Mor-phology of Small-Molecule Organic Semiconduc-tors. By P. Clancy,Chem. Mater., 23 (3), 522–543(2011).

AbstractThe author provides a short review of the status ofusing atomic- or molecular-scale simulations to lookat the phenomena associated with growing thin films ofsmall organic semiconductor materials, such as surfacediffusion, thin film growth, Ehrlich- Schwoebel step-edge barrier, etc. She offers a summary of the advan-tages and limitations of existing computational tools(Molecular Dynamics, kinetic Monte Carlo, ab initiomethods, etc.) and hint at method development thatmay help to deepen our understanding of “functional



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π”-materials. She also provides a deeper focus oncomputational, as well as related experimental, stud-ies of fundamental questions related to the thin-filmgrowth of a representative member of this class ofmaterials, namely, pentacene, on a variety of substratesfrom insulating oxides to metals, and shows resultsfor some other organic semiconductor members of theclass, wherever possible. 222 References.

• Tailored Organic Electro-optic Materials and TheirHybrid Systems for Device Applications. By J. Luo,S. Huang, Z. Shi, B. M. Polishak, X.-H. Zhou andA. K.-Y. Jen,Chem. Mater., 23(3), 544–553 (2011).

AbstractRecent development of tailored organic electric-optic(OEO) materials and their applications in hybrid devicesystems has been reviewed.

Hybrid systems encompass the optical and/or elec-trical components that form intimate contact with OEOmaterials, such as metal oxide barrier layers, solu-tion processable passive waveguides, silicon nanoslots,and photonic CMOS chips, etc. These systems offerunique advantages combining excellent properties andsimple processing for advanced photonic device plat-forms. Examples include the demonstration of low-Vπand low-loss EO modulators in hybrid polymersol- gel waveguides, CMOS-compatible hybrid poly-mer/silicon slotted waveguides, and EO polymer-cladsilicon nitride ring resonator modulators. This reviewalso provides a future prospect for the developmentof OEO materials and their hybrid systems. 32 Refer-ences.

• Charge-Carrier Transporting Graphene-TypeMolecules. By W. Pisula, X. Feng and K. Mullen,Chem. Mater., 23 (3), 554–567 (2011).

AbstractGraphene-type molecules, typically large polycyclicaromatic hydrocarbons (PAHs), have gained enor-mous interest because of their unique self-organizationbehavior and promising electronic properties for appli-cations in organic electronics. This article reviews thethermotropic behavior and supramolecular organiza-tion of discotic PAHs in the bulk as well as theirself-assembly on the surface at different length scales.

Applications of PAHs in field-effect transistors andsolar cells are discussed in light of various differentprocessing approaches from solution that ensure highorder and an adequate molecular arrangement in thedevice configuration. 118 References.

• Molecular Design and Synthetic Approaches toElectron-Transporting Organic Transistor Semicon-ductors. By B. J. Jung, N. J. Tremblay, M.-L. Yehand H. E. Katz,Chem. Mater., 23 (3), 568–582(2011).

AbstractThis review covers the various classes of molecu-lar structures that may be used as the basis for thesynthesis of organic semiconductors that favor elec-tron transport in field-effect transistors and relatedelectronic and optoelectronic devices. The types ofcompounds include tetracarboxylic diimides, hetero-cyclic oligomers, fullerenes, and metal complexes.Approaches to polymers are also mentioned. Althoughbrief discussions of transistor operation and applica-tions are included, the emphasis is on the rationale forchoosing these structures, and synthetic routes to them.Performance of exemplary compounds in transistors isalso discussed. 181 References.

• Small-Molecule, Nonfullerene Acceptors for Poly-mer Bulk Heterojunction Organic Photovoltaics. ByJ. E. Anthony,Chem. Mater., 23 (3), 583–590(2011).

AbstractIn the field of polymer bulk-heterojunction organicphotovoltaics, fullerenes and fullerene derivativesclearly play the dominant role as acceptor materials.Recently, a number of research efforts have focusedon the development of new small-molecule acceptorsfor this device configuration. Although few materialsprepared to-date have demonstrated power conversionefficiencies close to those achieved with fullerenes,numerous design rules and some interesting new mate-rials classes have been explored.

This short review will highlight the progress towardhigher efficiency in nonfullerene small-moleculeacceptors for organic solar cells. 41 References.



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• Electronic Processes at Organic-Organic Interfaces:Insight from Modeling and Implications for Opto-electronic Devices. By D. Beljonne, J. Cornil,L. Muccioli, C. Zannoni, J.-L. Bredas and F. Castet,Chem. Mater., 23 (3), 591–609 (2011).

AbstractThe authors report on the recent progress achieved inmodeling the electronic processes that take place atinterfaces betweenπ-conjugated materials in organicopto-electronic devices.

First, they provide a critical overview of the cur-rent computational techniques used to assess the mor-phology of organic: organic heterojunctions; highlightthe compromises that are necessary to handle largesystems and multiple time scales while preserving theatomistic details required for subsequent computationsof the electronic and optical properties. They thenreview some recent theoretical advances in describingthe ground-state electronic structure at heterojunctionsbetween donor and acceptor materials and highlight therole played by charge-transfer and long-range polar-ization effects. Finally, The authors discuss the model-ing of the excited-state electronic structure at organic:organic interfaces, which is a key aspect in the under-standing of the dynamics of photoinduced electron-transfer processes. 162 References.

• Electronic Energy Transfer and Quantum-Coherence inπ-Conjugated Polymers. By I. Hwangand G. D. Scholes,Chem. Mater., 23 (3), 610–620(2011).

AbstractElectronic energy transfer (EET) has been the subjectof intense research because of its significant contribu-tion to the photophysical properties of various materialsystems. Forπ-conjugated polymers, it has long beenaccepted that a classical hopping mechanism is domi-nant in the energy transfer dynamics because of a weakelectronic coupling. However, recent research revealsthat conjugated polymers, in fact, can have an elec-tronic coupling strong enough to preserve quantum-coherence.

In this review, the authors summarize the mainphotophysical features of conjugated polymers. They

discuss how electronic excited states evolve on var-ious time scales from femto-seconds to hundreds ofpico-seconds in terms of exciton relaxation, localiza-tion, and electronic energy transfer. The Forster energytransfer model and modifications needed for describingenergy transfer in conjugated polymers are described.They also discuss how chain conformation and its dis-order influence EET and the time scale of the evolutionof electronic excited states, and demonstrate how quan-tum coherence contributes to energy transfer dynamics.Recent research on exciton diffusion in various kindsof polymers is summarized. 141 References.

• Multifunctional Materials in High-PerformanceOLEDs: Challenges for Solid-State Lighting. ByH. Sasabe and J. Kido,Chem. Mater., 23 (3),621–630 (2011).

AbstractRecent advances in material chemistry have enabledwhite organic light-emitting device (OLED) efficacybeyond fluorescent tube efficacy up to 100 lm/W. Inthis short review, the authors explore recent develop-ments of small molecule-based multifunctional mate-rials in high-performance OLEDs, especially bluephosphorescent emitters, host materials, and electron-transporting materials. 102 References.

• Probing Hopping Conduction in Conjugated Molec-ular Wires Connected to Metal Electrodes. ByL. Luo, S. H. Choi and C. D. Frisbie,Chem. Mater.,23 (3), 631–630 (2011).

AbstractUnderstanding electrical transport processes inmolecules connected between metal electrodes is acentral focus in the field of molecular electronics andis important for both potential applications and funda-mental research purposes.

This short review summarizes recent progress inassembling and measuring strategies for long con-jugated molecular wires within molecular junctions,and introduces several new in situ methods to preparemolecular wires connected to electrodes. Followinga brief introduction to charge transport mechanisms,



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particular examples of molecular wires in the recent lit-erature are presented to discuss the influence of molec-ular length, temperature, and applied voltage on thetransport properties with emphasis on the tunneling-to-hopping transition. The review concludes with an out-look on future hopping transport experiments in longconjugated molecular wires. 114 References.

• Emerging Applications of Carbon Nanotubes. ByJ. M. Schnorr and T. M. Swager,Chem. Mater., 23(3), 646–657 (2011).

AbstractOn the basis of their unique electrical and mechani-cal properties, carbon nanotubes (CNTs) have attractedgreat attention in recent years. A diverse array ofmethods has been developed to modify CNTs and toassemble them into devices. On the basis of theseinnovations, many applications that include the use ofCNTs have been demonstrated. Transparent electrodesfor organic light-emitting diodes (OLEDs), lithium-ionbatteries, supercapacitors, and CNT-based electroniccomponents such as field-effect transistors (FETs) havebeen demonstrated. Furthermore, CNTs have beenemployed in catalysis and sensing as well as filters andmechanical and biomedical applications.

This review highlights illustrative examples fromthese areas to give an overview of applications ofCNTs. 165 References.

• Approaches to Solution-Processed MultilayerOrganic Light-Emitting Diodes Based on Cross-Linking. By C. A. Zuniga, S. Barlow andS. R. Marder, Chem. Mater., 23 (3), 658–681(2011).

AbstractThe fabrication of multilayer organic light-emittingdiodes (OLEDs)through solution processing presentschallenges, especially regarding dissolution of the firstlayer during deposition of a second layer. One possi-ble approach to this problem is to insolubilize the firstlayer using cross-linking. Cross-linking has also beenused to control the morphological stability and aggre-gation phenomena of the active organic materials.

In this short review, the authors discuss thealternative chemically, thermally, and photochemically

promoted cross-linking chemistries that have beenexamined in the context of OLEDs including: thehydrolysis of silicon compounds to form siloxanes;the polymerization of styrene, acrylate, and oxetanegroups; and the dimerization of trifluorovinyl ethers,benzocyclobutenes, and cinnamates. 68 References.

• One-Dimensional Nanostructures ofπ-ConjugatedMolecular Systems: Assembly, Properties, andApplications from Photovoltaics, Sensors, andNanophotonics to Nanoelectronics. By F. S. Kim,G. Ren and S. A. Jenekhe,Chem. Mater., 23 (3),682–732 (2011).

AbstractThis paper presents a comprehensive review ofthe literature on one-dimensional (1D) nanostruc-tures (nanowires, nanoribbons, nanotubes, nanobelts,and nanofibers) ofπ-conjugated small molecules,oligomers, and polymers.

The diverse methods used in assembling the molec-ular building blocks into 1D functional nanostruc-tures and nanodevices are discussed, including hardand soft template-assisted synthesis, electro-spinning,nanolithography, self-assembly in solution and atinterfaces, physical vapor transport, and other strate-gies. Optical, charge transport, electronic, and pho-toconductive properties of nanowires and nanotubesof selected classes ofπ-conjugated molecular sys-tems are discussed, highlighting unique features ofthe 1D nanostructures compared to 2D thin films.Overview of applications of these 1D organic nanos-tructures ranging from nanoscale light-emitting diodes,field-emission devices, organic photovoltaics, sen-sors/biosensors, spin-electronics, and nanophotonics tonanoelectronics is then given. The final section pro-vides brief concluding comments on the status of thefield and on areas of outstanding challenges and oppor-tunities for future work. 592 References.

• π-Conjugated Polymers for Organic Electronics andPhotovoltaic Cell Applications. By A. Facchetti,Chem. Mater., 23 (3), 733–758 (2011).

AbstractThe optoelectronic properties of polymeric semicon-ductor materials can be utilized for the fabrication of



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organic electronic and photonic devices. When keystructural requirements are met, these materials exhibitunique properties such as solution processability, largecharge transporting capabilities, and/or broad opticalabsorption.

In this review, recent developments in thearea of π-conjugated polymeric semiconductors fororganic thin-film (or field-effect) transistors (OTFTsor OFETs) and bulk-heterojunction photovoltaic (orsolar) cell (BHJ-OPV or OSC) applications are sum-marized and analyzed. 155 References.

• Using the Dynamic Bond to Access Macroscopi-cally Responsive Structurally Dynamic Polymers.By R. J. Wojtecki, M. A. Meador and S. J. Rowan,Nature Mater., 10 (1), 14–27 (2011).

AbstractNew materials that have the ability to reversibly adaptto their environment and possess a wide range ofresponses ranging from self-healing to mechanicalwork are continually emerging. These adaptive sys-tems have the potential to revolutionize technologiessuch as sensors and actuators, as well as numerousbiomedical applications.

The authors describe the emergence of a new trendin the design of adaptive materials that involves the useof reversible chemistry (both non-covalent and cova-lent) to program a response that originates at the mostfundamental (molecular) level. Materials that make useof this approach — structurally dynamic polymers —produce macroscopic responses from a change in thematerial’s molecular architecture. That is, the rear-rangement or reorganization of the polymer compo-nents, or polymeric aggregates. This design approachrequires careful selection of the reversible/dynamicbond used in the construction of the material to con-trol its environmental responsiveness. 111 References.

• Single Dopants in Semiconductors. ByP. M. Koenraad and M. E. Flatte,Nature Mater.,10 (2), 91–100 (2011).

AbstractThe sensitive dependence of a semiconductor’s elec-tronic, optical and magnetic properties on dopants hasprovided an extensive range of tunable phenomena to

explore and apply to devices. Recently it has becomepossible to move past the tunable properties of anensemble of dopants to identify the effects of a soli-tary dopant on commercial device performance as wellas locally on the fundamental properties of a semicon-ductor. New applications that require the discrete char-acter of a single dopant, such as single-spin devices inthe area of quantum information or single-dopant tran-sistors, demand a further focus on the properties of aspecific dopant.

This article describes the huge advances in the pastdecade towards observing, controllably creating andmanipulating single dopants, as well as their applica-tion in novel devices which allow opening the newfield of ‘solotronics’ (solitary dopant optoelectronics).117 References.

• Functional Soft Materials from Metallopoly-mers and Metallosupramolecular Polymers. ByG. R. Whittell, M. D. Hager, U. S. Schubert andI. Manners,Nature Mater., 10 (3), 176–188 (2011).

AbstractSynthetic polymers containing metal centres areemerging as an interesting and broad class of eas-ily processable materials with properties and func-tions that complement those of state-of-the-art organicmacromolecular materials. A diverse range of differ-ent metal centres can be harnessed to tune macro-molecular properties, from transition- and main-groupmetals to lanthanides. Moreover, the linkages thatbind the metal centres can vary almost continuouslyfrom strong, essentially covalent bonds that lead toirreversible or ’static’ binding of the metal to weakand labile, non-covalent coordination interactions thatallow for reversible, ’dynamic’ or ’metallosupramolec-ular’, binding.

Here, the authors review recent advances and chal-lenges in the field and illustrate developments towardsapplications as emissive and photovoltaic materials;as optical limiters; in nanoelectronics, informationstorage, nanopatterning and sensing; as macromolec-ular catalysts and artificial enzymes; and as stimuli-responsive materials. They focus on materials in whichthe metal centres provide function; although they canalso play a structural role, systems where this is solelytheir purpose have not been discussed. 125 References.



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• Strain Effects in Low-Dimensional Transition MetalOxides. By J. Cao and J. Wu,Mater Sci. & Engg. R.,71 (2–4), 35–52 (2011).

AbstractTransition metal oxides offer a wide spectrum of prop-erties which provide the foundation for a broad rangeof potential applications. Many of these propertiesoriginate from intrinsic coupling between lattice defor-mation and nanoscale electronic and magnetic order-ing. Lattice strain thus has a profound influence onthe electrical, optical, and magnetic properties of thesematerials. Recent advances in materials processinghave led to the synthesis of low-dimensional single-crystal transition metal oxides, namely, epitaxial ultra-thin films and free-standing nano/microwires. Unlikebulk materials, these systems allow external tuning ofuniform strain in these materials to tailor their proper-ties and functionalities.

This paper provides a comprehensive reviewof recent developments in studies of strain effectsin transition metal oxide ultra-thin films andnano/microwires. The authors focus on the work ofstrain-controlled electromechanical response in piezo-electric oxides and strain-induced metal–insulator tran-sitions as well as domain physics in strongly correlatedelectron oxides. Related nanoscale device applicationssuch as strain sensing and power generation are high-lighted as well. 206 References.

• Electromigration in Submicron Interconnect Fea-tures of Integrated Circuits. By H. Ceric andS. Selberherr,Mater Sci. & Engg. R.,71 (5–6),53–86 (2011).

AbstractElectromigration (EM) is a complex multiphysicsproblem including electrical, thermal, and mechanicalaspects. Since the first work on EM was published in1907, extensive studies on EM have been conductedtheoretically, experimentally, and by means of com-puter simulation. Today EM is the most significantthreat for interconnect reliability in high performanceintegrated circuits.

The intention of this review is to present the mostimportant aspects of theoretical and experimental EM

investigations together with a brief history of the devel-opment of the main concepts and methods. The authorspresent an overview of EM models from their originsin classical materials science methods up to the mostrecent developments for submicron interconnect fea-tures, as well as the application of ab initio and firstprinciple methods. The main findings of experimen-tal studies, important for any model development andapplication, are also presented. 161 References.

• Medium Chain Length Polyhydroxyalkanoates,Promising New Biomedical Materials for theFuture. By R. Rai, T. Keshavarz, J. A. Roether,A. R. Boccaccini and I. Roy,Mater Sci. & Engg. R.,72 (3), 29–47 (2011).

AbstractMedium chain length polyhydroxyalkanoates, mcl-PHAs (C6–C14 carbon atoms), are polyesters ofhydroxyalkanoates produced mainly by fluorescentPseudomonadsunder unbalanced growth conditions.These mcl-PHAs, which can be produced usingrenewable resources are biocompatible, biodegradableand thermo-processable. They have low crystallinity,low glass transition temperature, low tensile strengthand high elongation to break, making them elas-tomeric polymers. Mcl-PHAs and their copolymersare suitable for a range of biomedical applicationswhere flexible biomaterials are required, and aremore structurally diverse than short chain lengthPHAs and hence can be more readily tailored forspecific applications. Composites have also beenfabricated using mcl-PHAs and their copolymers,with single walled carbon nanotubes and poly(3-hydroxbutyrate-co-3-hydroxyhexanoate) [P(3HB-co-3HHx)] combined with hydroxyapatite. Because ofthese attractive properties, Mcl-PHAs and their com-posites are being increasingly used for biomedicalapplications. However, studies remain limited mainlyto P(3HO) and the copolymer P(3HB-co-3HHx),which are the only mcl-PHAs available in large quan-tities.

In this review, the authors have consolidatedcurrent knowledge on the properties and biomedi-cal applications of these elastomeric mcl-PHAs, theircopolymers and their composites. 142 References.



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• Bionanoelectronics. By A. Noy,Adv. Mater., 23 (7),807–820 (2011).

AbstractEvery cell in a living organisms performs a complexarray of functions using a vast arsenal of proteins,ion channels, pumps, motors, signaling molecules, andcargo carriers. With all the progress that humankindhas made to date in the development of sophisticatedmachinery and computing capabilities, understandingand communicating with living systems on that levelof complexity lags behind. A breakthrough in thesecapabilities could only come if a way is found to inte-grate biological components into artificial devices. Thecentral obstacle for this vision of bionanoelectronics isthe absence of a versatile interface that facilitates two-way communication between biological and electronicstructures. 1D nanomaterials, such as nanotubes andnanowires, open up the possibility of constructing tightinterfaces that could enable such bidirectional flow ofinformation.

This review discusses the overall progress in build-ing such interfaces on the level of individual proteinsand whole cells and focuses on the latest efforts tocreate device platforms that integrate membrane pro-teins, channels, and pumps with nanowire bioelectron-ics. 104 References.

• Magnetic Materials and Devices for the 21st Cen-tury: Stronger, Lighter, and More Energy Effi-cient. By O. Gutfleisch, M. A. Willard, E. Bruck,C. H. Chen, S. G. Sankar and J. P. Liu,Adv. Mater.,23 (7), 807–820 (2011).

AbstractA new energy paradigm, consisting of greater relianceon renewable energy sources and increased concernfor energy efficiency in the total energy lifecycle,has accelerated research into energy-related technolo-gies. Due to their ubiquity, magnetic materials playan important role in improving the efficiency andperformance of devices in electric power generation,conditioning, conversion, transportation, and otherenergy-use sectors of the economy.

This review focuses on the state-of-the-art hardand soft magnets and magnetocaloric materials, with

an emphasis on their optimization for energy appli-cations. Specifically, the impact of hard magnets onelectric motor and transportation technologies, of softmagnetic materials on electricity generation and con-version technologies, and of magnetocaloric materialsfor refrigeration technologies, are discussed. The syn-thesis, characterization, and property evaluation of thematerials, with an emphasis on structure–property rela-tionships, are discussed in the context of their respec-tive markets, as well as their potential impact on energyefficiency. Finally, considering future bottlenecks inraw materials, options for the recycling of rare-earthintermetallics for hard magnets are discussed. 134 Ref-erences.

• Recent Progresses on Materials for Electrophos-phorescent Organic Light-Emitting Devices. ByL. Xiao, Z. Chen, B. Qu, J. Luo, S. Kong, Q. Gongand J. Kido,Adv. Mater., 23 (8), 926–952 (2011).

AbstractAlthough organic light-emitting devices have beencommercialized as flat panel displays since 1997,only singlet excitons were emitted. Full use of sin-glet and triplet excitons, electrophosphorescence, hasattracted increasing attentions after the premier workmade by Forrest, Thompson, and co-workers. In fact,red electrophosphorescent dye has already been usedin sub-display of commercial mobile phones since2003. Highly efficient green phosphorescent dye isnow undergoing of commercialization. Very recently,blue phosphorescence approaching the theoretical effi-ciency has also been achieved, which may overcomethe final obstacle against the commercialization of fullcolor display and white light sources from phospho-rescent materials. Combining light out-coupling struc-tures with highly efficient phosphors, white emissionwith an efficiency matching that of fluorescent tubes(90 lm/W) has now been realized. It is possible to tunethe color to the true white region by changing to adeep blue emitter and corresponding wide gap host andtransporting material for the blue phosphor.

In this article, recent progresses in red, green, blue,and white electrophosphorescent materials for OLEDsare reviewed, with special emphasis on blue elec-trophosphorescent materials. 228 References.



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• Strategies for Post-Synthesis Alignment and Immo-bilization of Carbon Nanotubes. By T. Druzhinina,S. Hoeppener and U. S. Schubert,-Adv. Mater.,23(8), 953–970 (2011).

AbstractCarbon nanotubes (CNTs) have developed into astandard material used as a building block fornanotechnological developments. Based on the uniqueproperties that make CNTs useful for many differentapplications in nanotechnology,optics, electronics, andmaterial science, there has been a rapid development ofthis research area and many different applications haveemerged in the past few years. Frequently, the align-ment and immobilization of CNTs play an importantrole for many applications and different strategies, inparticular post-synthesis approaches, can be applied.

Recent developments of different techniques toimmobilize and align carbon nanotubes are discussedand classified into three main categories: chemicalimmobilization and alignment, physical immobiliza-tion and alignment, and the use of external fields forthese purposes. Many of the techniques involve mul-tiple steps and may also cross these rather crudelydefined boundaries. As such, the techniques are clas-sified according to their most important or unique step.169 References.

• Bimetallic Nanocrystals: Liquid-Phase Synthesisand Catalytic Applications. By D. Wang and Y. Li,Adv. Mater., 23 (9), 1044–1060 (2011).

AbstractBimetallic nanocrystals (NCs) with core/shell, het-erostructure, or intermetallic and alloyed structuresare emerging as more important materials thanmonometallic NCs. They are expected to displaynot only a combination of the properties associatedwith two distinct metals, but also new properties andcapabilities due to a synergy between the two met-als. More importantly, bimetallic NCs usually showcomposition-dependent surface structure and atomicsegregation behavior, and therefore more interestingapplied potentials in various fields including elec-tronics, engineering, and catalysis. Compared withmonometallic NCs, preparation of bimetallic NCs ismuch more complicated and difficult to be achieved. In

recent years, researchers from many groups have madegreat efforts in this area. This review highlights therecent progress in the chemical synthesis of bimetal-lic NCs. The control over morphology, size, compo-sition, and structure of bimetallic NCs as well as theexploration of their properties and applications are dis-cussed. 111 References.

• Recent Progress in Multiferroic MagnetoelectricComposites: from Bulk to Thin Films. By J. Ma,J. Hu, Z. Li and C.-W. Nan,Adv. Mater., 23 (9),1062–1087 (2011).

AbstractMultiferroic magnetoelectric composite systems suchas ferromagnetic-ferroelectric heterostructures haverecently attracted an ever-increasing interest and pro-voked a great number of research activities, drivenby profound physics from coupling between ferroelec-tric and magnetic orders, as well as potential applica-tions in novel multifunctional devices, such as sensors,transducers, memories, and spintronics.

In this review, the authors try to summarize whatremarkable progress in multiferroic magnetoelectriccomposite systems has been achieved in most recentfew years, with emphasis on thin films; and to describeunsolved issues and new device applications whichcan be controlled both electrically and magnetically.233 References.

• Dry Autoclaving for the Nanofabrication of Sul-fides, Selenides, Borides, Phosphides, Nitrides, Car-bides, and Oxides. By V. G. Pol, S. V. Pol andA. Gedanken,Adv. Mater., 23 (10), 1179–1190(2011).

AbstractThis review compiles various nanostructures fabricatedby a distinct “dry autoclaving” approach, where thechemical reactions are carried out without solvents;above the dissociation temperature of the chemical pre-cursor(s) at elevated temperature in a closed reactor.The diversity to fabricate carbides (SiC, Mo2C, WC),oxides (VOx-C, ZnO, Eu2O3, Fe3O4, MoO2), hex-aborides (LaB6, CeB6, NdB6, SmB6, EuB6, GdB6),nitrides (TiN, NbN, TaN), phosphides (PtP2, WP),sulfides (ZnS, FeS/C, SnS/C, WS2, WS2/C), and



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selenides (Zn1−xMnxSe/C, Cd1−xMnxSe/C), with var-ious shapes and sizes is accounted with plausible appli-cations. This unique single-step, solvent-free syntheticprocess opens up a new route in the growing nanoma-terials science, owing to its considerable advantages onthe existing approaches. 116 References.

• Dynamic Aspects of Films Prepared by a SequentialDeposition of Species: Perspectives for Smart andResponsive Materials. By P. Lavalle, J.-C. Voegel,D. Vautier, B. Senger, P. Schaaf and V. Ball,Adv.Mater., 23 (10), 1191–1221 (2011).

AbstractThe deposition of surface coatings using a step-by-step approach from mutually interacting species allowsthe fabrication of so called “multilayered films”. Thesecoatings are very versatile and easy to produce in envi-ronmentally friendly conditions, mostly from aque-ous solution. They find more and more applications inmany hot topic areas, such as in biomaterials and nano-electronics but also in stimuli-responsive films.

The authors aim to review the most recent devel-opments in such stimuli-responsive coatings based onlayer-by-layer (LBL) depositions in relationship to theproperties of these coatings. The most investigatedstimuli are based on changes in ionic strength, tem-perature, exposure to light, and mechanical forces. Thepossibility to induce a transition from linear to expo-nential growth in thickness and to change the chargecompensation from “intrinsic” to “extrinsic” by con-trolling parameters such as temperature, pH, and ionicstrength are the ways to confer their responsivenessto the films. Chemical post-modifications also allowto significantly modify the film properties. 405 Refer-ences.

• Thermoforming of Film-based BiomedicalMicrodevices. By R. Truckenmuller, S. Giselbrecht,N. Rivron, E. Gottwald, V. Saile, A. van den Berg,M. Wessling and C. van Blitterswijk,Adv. Mater.,23 (11), 1311–1329 (2011).

AbstractFor roughly ten years now, a new class of polymermicromoulding processes comes more and more into

the focus both of the microtechnology and the biomed-ical engineering community. These processes can besubsumed under the term “microthermoforming”. Inmicrothermoforming, thin polymer films are heated toa softened, but still solid state and formed to thin-walled microdevices by three-dimensional stretching.The high material coherence during forming is in con-trast to common polymer microreplication processeswhere the material is processed in a liquid or flowingstate. It enables the preservation of premodifications ofthe film material.

In this article, the authors review the still youngstate- of –the- art of microthermoforming technologyas well as its first applications. So far, the applica-tions are mainly in the biomedical field. They bene-fit from the fact that thermoformed microdevices haveunique properties resulting from their special, unusualmorphology. The focus of this article is on the impactof the new class of micromoulding processes and theprocessed film materials on the characteristics of themoulded microdevices and on their applications. 73References.

• Smectic Liquid Crystal Defects for Self-Assemblingof Building Blocks and their Lithographic Appli-cations. By Y. H. Kim, D. K. Yoon, H. S. Jeong,O. D. Lavrentovich and H.-T. Jung,Adv. Funct.Mater., 21 (4), 610–627 (2011).

AbstractRecently, it has been reported that liquid crystal (LC)defects can be used to create highly periodic templatesby controlling the surface anchoring and the elasticproperties of LC molecules. The self-assembled defectordering of the LC materials takes advantage of theability to achieve fast stabilization of molecular order-ing and structure due to the reversible and non-covalentinteractions of the LC molecules.

In this article, the defect structures of liquid crys-talline materials will be demonstrated by the surfaceanchoring and elastic properties. A particular focusis on the focal conic domains (FCDs) that are com-monly observed in SmA liquid crystals and their lamel-lar lyotropic counterparts, which form periodic defectordered structures. In addition, methodologies for cre-ating lithographic templates from the defect order will



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be described. Finally, the review closes with a discus-sion of toric focal conic domain arrays that have beenfabricated in this manner and used for various applica-tions. 95 References.

• Carbide-Derived Carbons – From Porous Networksto Nanotubes and Graphene. By V. Presser, M. Heonand Y. Gogotsi,Adv. Funct. Mater., 21 (5), 810–833(2011).

AbstractCarbide-derived carbons (CDCs) are a large familyof carbon materials derived from carbide precursorsthat are transformed into pure carbon via physical(e.g., thermal decomposition) or chemical (e.g., halo-genation) processes. Structurally, CDC ranges fromamorphous carbon to graphite, carbon nanotubes orgraphene. For halogenated carbides, a high level ofcontrol over the resulting amorphous porous carbonstructure is possible by changing the synthesis con-ditions and carbide precursor. The large number ofresulting carbon structures and their tunability enablesa wide range of applications, from tribological coatingsfor ceramics, or selective sorbents, to gas and electricalenergy storage. In particular, the application of CDC insupercapacitors has recently attracted much attention.

This review summarizes key aspects of CDC syn-thesis, properties, and applications. It is shown thatthe CDC structure and properties are sensitive tochanges of the synthesis parameters. Understandingof processing–structure–properties relationships facil-itates tuning of the carbon material to the requirementsof a certain application. 237 References.

• Materials Chemistry of Fullerene (C60) Derivatives.By A. M. Lopez, A. M. -Alonso and M. Prato,J. Mater. Chem.,21 (5), 1305–1318 (2011).

AbstractDespite the increasing interest of the scientific com-munity in carbon nanotubes and graphene, fullereneC60 still plays an important role in the family ofnanocarbons. A quarter of a century of research onfullerenes has been dedicated to understanding the wayto produce stable, well-characterized and highly sol-uble fullerene derivatives, which retain the original

properties of C60. The applications in a wide num-ber of fields, especially on new materials design, haveenriched the literature with fascinating examples wherefullerenes are directly involved.

The authors report a brief summary of recentachievements in some exciting applications offullerene derivatives. 157 References.

• A Review of Powder Modifications in Con-ventional Glass-Ionomer Dental Cements. ByA. Moshaverinia, N. Roohpour, W. W. L. Chee andS. R. Schricker,J. Mater. Chem.,21 (5), 1319–1328(2011).

AbstractGlass-ionomer dental cements (GICs) have proven tobe useful in several areas of dentistry such as restora-tive dentistry. Glass-ionomers are aqueous cementsformed by the reaction of an acidic polymer and a basicglass in the presence of water. The oral environmentpresents many challenges to the longevity of restorativematerials. Glass-ionomer cements have many proper-ties that are clinically useful and promote longevity.Importantly, GICs adhere to moist tooth structure with-out any pretreatment, and provide a prolonged periodof fluoride release, which inhibits recurrent tooth decay(caries). These properties together with acceptable aes-thetics and biocompatibility make these materials pop-ular and desirable for medical and dental applications.However, glass-ionomer dental cements have limita-tions that prevent broader clinical adaptation such aspoor mechanical properties and moisture sensitivity.Many significant changes and modifications to thechemistry of the acidic polymers and basic glasses andto the formulation of the cements have been made toaddress these limitations.

In this review, advances in the development ofthe basic glasses and other reinforcing agents are dis-cussed. An overview of the chemistry of glass-ionomercements is discussed followed by an in-depth discus-sion of the chemistry of novel basic glasses and rein-forcing additives. 94 References.

• Chalcogenoarene Semiconductors: New Ideas fromOld Materials. By L. Zhang, S. M. Fakhouri, F. Liu,J. C. Timmons, N. A. Ran and A. L. Briseno,J. Mater. Chem.,21 (5), 1329–1337 (2011).



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AbstractThere are certain aspects of the electronic and pack-ing behavior of planar aromatic molecules contain-ing exocyclic chalcogen atoms (i.e., sulfur, selenium,tellurium) which need considerable re-enlightenment.This class of semiconductors was once regarded asnext-generationπ-donors for applications in charge-transfer complexes. With the advent of new devicetechnologies such as light-emitting diodes, solar cells,and organic transistors, the interest in charge-transfercomplexes eventually tapered off. However, significantprogress in the use of this class of materials in mod-ern organic devices has been reported over the last fiveyears.

In this article, the authors review the exocyclicarenes with chalcogen atoms inperi-positions, sum-marize synthetic routes to these compounds and takea close look at their basic properties. Particular empha-sis is placed upon their packing arrangements andthe effect of exocyclic chalcogen atoms on the crys-tal packing motifs. Selected example applications fromthis class of materials in different fields are highlighted.As a final note, the authors provide a prediction fortheir use in mainstream applications such as energyand fundamental charge transport/generation. 76 Ref-erences.

• Alkoxy-Substituted Poly(Arylene-Ethynylene)-Alt-Poly(Arylene-Vinylene)s: Synthesis, Electrolu-minescence and Photovoltaic Applications. ByD. A. M. Egbe, H. Neugebauer and N. S. Sariciftci,J. Mater. Chem.,21 (5), 1338–1349 (2011).

AbstractPoly (arylene-ethynylene)-alt-poly(arylene-vinylene)s(PAE-PAVs) combine the intrinsic features of bothpoly (arylene-ethynylene) (PAE) and poly(arylene-vinylene) (PAV) in a single polymeric backbone.They exhibit enhanced electron affinity, as com-pared to parent poly (p-phenylene-vinylene) (PPV),making electron injection easier, placing them aspotential candidates for low turn-on voltage organiclight emitting diodes (OLEDs). Depending on thechemical structures, PAE-PAVs have been efficientlyused either as donor materials in polymer-PCBM

(phenyl-C61-butyric acid methylester) or polymer-Vinazene (2-vinyl-4,5-dicyanoimidazole) bulk hetero-junction solar cells, or as acceptor materials inpolymer-polymer bilayer and blend solar cells.

This article reviews the synthesis and prop-erties (electroluminescence and photovoltaic) ofπ-conjugated alkoxy-substituted PAE-PAVs designedby the authors, and which were obtained either byHorner–Wadsworth–Emmons olefination reaction ofluminophoric dialdehydes with bisphosphonate esters,or Knoevenagel reaction of the same dialdehydes withdinitriles. 71 References.

• Exotic Materials for Bio-Organic Electronics. ByM. Irimia-Vladu, N. S. Sariciftci and S. Bauer,J. Mater. Chem.,21 (5), 1350–1361 (2011).

Abstract‘Exotic materials have become the focus of recentdevelopments in organic electronics that envision bio-compatibility, biodegradability, and sustainability forlow-cost, large-volume electronic components.

In this brief review, the authors discuss firstly theuse of paper, leather, silk, hard gelatine, and bio-degradable plastics as substrates for electronic devices,and secondly smoothing agents, such as polydimethyl-siloxane and aurin. Thirdly, they describe DNA andnucleobases as examples of exotic dielectrics with lowdielectric losses and leakage currents as well as suf-ficiently high dielectric breakdown strength. Fourthly,natural, nature-inspired, and common-commoditysemiconductors are presented that broaden the mate-rials base for organic semiconductors and may inspirefurther work to identify semiconductors that are stablein the face of changing environmental conditions yetdegradable at the end of their product lifetime. Sus-tainability in organic electronics, energy storage, andemerging concepts are also reviewed briefly. Researchon “exotic” organic materials may ultimately resultin environmentally safe “green electronic” products.56 References.

• From Molecular Mechanochemistry to Stress-Responsive Materials. By A. L. Black,J. M. Lenhardt and S. L. Craig,J. Mater. Chem.,21 (6), 1655–1663 (2011).



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AbstractCurrent activity in, and future prospects for, theincorporation of mechanochemically active functionalgroups (‘mechanophores’) into polymers is reviewed.

This area of research is treated in the contextof two categories. The first category is the devel-opment of new chemistry in the service of mate-rial science, through the design and synthesis ofmechanophores to provide stress-sensing and/or stress-responsive elements in materials. The second categoryis the reverse—the development of new material archi-tectures that efficiently transmit macroscopic forces totargeted molecules in order to generate chemical reac-tivity that is inaccessible by other means. 83 Refer-ences.

• Carbon Nanospheres: Synthesis, PhysicochemicalProperties and Applications. By A. Nieto-Marquez,R. Romero, A. Romero and J. L. Valverde,J. Mater.Chem.,21 (6), 1664–1672 (2011).

AbstractThe discovery of carbon nanostructures, essentiallycarbon nanotubes (CNT) and carbon nanofibres (CNF)has led to a big effort devoted to their synthesis, charac-terization, surface modification and use. Indeed, thesestructures have encountered application in a wide rangeof technological fields, such as adsorption, catalysis,hydrogen storage or electronics. Apart from the fil-amentous arrange of graphene sheets conducting toCNT or CNF, carbon can bond in other different waysto create structures with dissimilar properties. The pair-ing of pentagonal and heptagonal carbon rings canresult in the formation of carbon nanospheres (CNS).This novel nanostructure has only now started to attractsignificant research activity. In its spherical arrange-ment, the graphite sheets are not closed shells butrather waving flakes that follow the curvature of thesphere, creating many open edges at the surface. Con-trary to the chemically inert C60, the unclosed graphiticflakes provide reactive “dangling bonds” that are pro-posed to enhance surface reactions, establishing CNSas good candidates for catalytic and adsorption appli-cations.

Despite the embryonic stage of the field and theexisting data being too scattered, this work is aimed to

provide a comprehensive review of the existing litera-ture related to CNS, exploring the different preparationroutes employed, the critical characterization results aswell as the applications studied so far. 105 References.

• Two-Dimensional Nanoparticle Organization usingBlock Copolymer Thin Films as Templates. ByM. J. Pavan and R. Shenhar,J. Mater. Chem.,21(7),2028–2040 (2011).

AbstractThe creation of ordered nanoparticle assemblies is oneof the main prerequisites for the utilization of nanopar-ticles in advanced device applications. However, whileconsiderable progress has been made in the precisionsynthesis of high quality, uniform nanoparticles of dif-ferent compositions, sizes and shapes, our ability toorganize them into ordered structures still faces majorchallenges.

This Article focuses on a facile approach developedin recent years for the fabrication of two-dimensionallyorganized nanoparticle assemblies, which is based onpatterning as a simple and straightforward assemblymechanism and on block copolymer films as easily cre-ated templates. 62 References.

• Recent Advances in Making Nano-Sized TiO2

Visible-Light Active through Rare-Earth MetalDoping. By S. Bingham and W. A. Daoud,J. Mater. Chem.,21 (7), 2041–2050 (2011).

AbstractDoping with metals and non-metals is a popular tech-nique that facilitates visible light activity of titaniumdioxide. More recently, rare-earth metals have showntremendous potential as dopants not only in red-shifting the absorption but also in improving the pho-tocatalysis of TiO2.

This article discusses recent developments in mak-ing TiO2 visible-light active through single and co-doping with rare earth metals. An emphasis is placedon wet chemical techniques and their associated effectson the phase, adsorption, surface area, and photocat-alytic activity of TiO2. New techniques, such as elec-trospinning, magnetron sputtering, co-precipitation,and complexation, as well as the use of nanotubes andphysical support are also discussed. 52 References.



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• Efficient Photocatalytic Degradation of OrganicsDiluted in Water and Air using TiO2 Designedwith Zeolites and Mesoporous Silica Materials. ByY. Kuwahara and H. Yamashita,J. Mater. Chem.,21(8), 2407–2016 (2011).

AbstractTitanium dioxide (TiO2) is a promising photocatalystfor degradation of organic compounds ideally underenvironmentally benign conditions. This paper reviewsrecent developments in designing TiO2-sorbent hybridphotocatalysts, especially those supported on orderednano-porous silica materials including zeolites andmesoporous silicas, with the objective of fabricat-ing efficient photodegradation systems toward organiccompounds diluted in water and air.

This review also describes the basic features of zeo-lites and mesoporous silica, adsorption kinetics on theirsurfaces, and the principles of surface modificationtechniques, and highlights that the hydrophobic natureof support materials can offer significant enhancementin photodegradation. Additionally, the several emerg-ing synthetic approaches for related zeolitic materi-als from siliceous industrial wastes, which indicatethe realization of energy-saving and recycling-orientedmanufacturing processes in this field, are discussed.54 References.

• The Impact of Carbon Materials on the Hydro-gen Storage Properties of Light Metal Hydrides. ByP. Adelhelm and P. E. de Jongh,J. Mater. Chem.,21(8), 2417–2027 (2011).

AbstractThe safe and efficient storage of hydrogen is still oneof the remaining challenges towards fuel cell poweredcars. Metal hydrides are a promising class of materialsas they allow the storage of large amounts of hydro-gen in a small volume at room temperature and lowpressures. However, usually the kinetics of hydrogenrelease and uptake and the thermodynamic propertiesdo not satisfy the requirements for practical applica-tions. Therefore current research focuses on catalysisand the thermodynamic tailoring of metal hydride sys-tems. Surprisingly, carbon materials used as additiveor support are very effective to improve the hydro-gen storage properties of metal hydrides allowing fast

kinetics and even a change in the thermodynamic prop-erties. Even though the underlying mechanisms are notalways well understood, the beneficial effect is proba-bly related to the peculiar structure of the carbon mate-rials.

This article gives an introduction to the differentcarbon materials, an overview of the preparation strate-gies to synthesize carbon/hydride nanocomposites, andhighlights the beneficial effect of carbon by discussingtwo important hydrides: MgH2 and NaAlH4. 105 Ref-erences.

• Lateral Interactions at Functional Monolayers. ByS.-H. Hsu, D. N. Reinhoudt, J. Huskens andA. H. Velders,J. Mater. Chem.,21 (8), 2428–2444(2011).

AbstractThis article gives an overview of the recent literatureregarding lateral molecular interactions in monolayers.The first part (Section 3) focuses on systems of self-assembled monolayers on metal surfaces, discussingthe covalent and noncovalent interactions of the termi-nal functionality or between the molecular chains ofthe molecules. The second part (Section 4) highlightsthe intermolecular interactions of monolayers on sili-con and metal oxide surfaces. The third part (Section5) presents examples of lateral interactions on receptorsurfaces. A focus in all parts is on examples of lateralinteractions in monolayers in which electron or energytransfer occurs. 91 References.

• Composites of Functional Polymeric Hydrogelsand Porous Membranes. By Q. Yang, N. Adrus,F. Tomicki and M. Ulbricht,J. Mater. Chem.,21 (9),2783–2811 (2011).

AbstractPolymeric hydrogels are a most interesting class of“soft matter” with several established and many morepossible applications as functional materials. In thisreview, the authors focus on the combination of poly-meric hydrogels and porous membranes which leads tocomposites with promising functionality, for example,mass separations, sensing and analytics, (bio)catalysis,biomedical engineering and micro-system technolo-gies.



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The combination of a rigid porous membrane witha soft functional hydrogel by a suited preparation tech-nique enables that the functionality of the hydrogel canbe applied in a unique way. The most important prepa-ration strategies for hydrogel composite membranes,i.e., pore-filling, various surface-grafting methods andcombinations thereof, are discussed. The structuraldiversity of the hydrogels is based on the use of a widerange of synthetic monomers, but biopolymers or theirderivatives can also be applied. The interplay of themembrane pore structure, the structure of the hydro-gel and the distribution of the hydrogel in the porespace can lead to different types of composite mem-branes with completely different potential applications.The focus is on promising examples for the varioustypes of functional composite membranes, i.e., macro-porous membrane adsorbers, anti-fouling filtrationmembranes, hydrogel-based ultrafiltration membranes,other separation membranes with pore-filling hydrogelas selective material, stimuli-responsive membranesand porous membrane valves and gates, as well as bio-compatible or bioactive membranes. 233 References.

• Stimuli-Responsive, Mechanically-Adaptive Poly-mer Nanocomposites. By L. Hsu, C. Weder andS. J. Rowan,J. Mater. Chem.,21 (9), 2812–2822(2011).

AbstractStimuli-responsive nanocomposites composed of func-tional nanoparticles that are embedded within polymermatrices have begun to attract much attention as a newgeneration of mechanically-adaptive materials. Thesesystems exhibit properties that exploit the influenceof the filler beyond static mechanical reinforcement.The underlying mechanisms of these new nanomateri-als typically involve an external stimulus that impactsthe composite material, altering its bulk mechanics.

In this article, the key components currently beingutilized to create polymeric nanocomposites with mor-phing mechanical properties are discussed, along withpotential applications that provide the motivation forthe development and investigation of such materials.60 References.

• Core–Shell Structural Iron Oxide Hybrid Nanopar-ticles: from Controlled Synthesis to Biomedical

Applications. By L. Zhou, J. Yuan and Y. Wei,J. Mater. Chem.,21 (9), 2823–2840 (2011).

AbstractSuperparamagnetic iron oxide nanoparticles havereceived great research attention due to their widespectrum of potential applications. Core–shell struc-tures with iron oxide nanoparticles as the core andwith covalently grafted organic polymers as the shell,which has specific functions, such as biocompatibil-ity, fluorescence, and biological activity have been syn-thesised. These nanostructured compounds could findnumerous biomedical applications.

This article provides a review on the syntheticmethodologies for building such magnetic core–shell structures, and on their applications in targeteddrug delivery, enhanced magnetic resonance imag-ing (MRI), enzyme immobilization, hyperthermia andbiosensors. Promising future directions of this activeresearch field are also discussed. 136 References.

• Graphene: Preparation and Structural Perfection.By M. Inagaki, Y. A. Kim and M. Endo,J. Mater. Chem.,21 (10), 3280–3294 (2011).

AbstractThree basic processes for the production of mono-layer graphene are reviewed: cleavage of graphite crys-tals, exfoliation of graphite intercalation compoundsand chemical vapor deposition. The relationship of thestructural perfection of the obtained thin flakes to thepreparation method is discussed. 196 References.

• Solution-Chemistry Approach to Graphene Nanos-tructures. By X. Yan and L.-S. Li,J. Mater. Chem.,21 (10), 3295–3300 (2011).

AbstractGraphene has many novel optical and electrical proper-ties desirable for applications in future electro-opticaldevices. Graphene nanostructures are especially attrac-tive for their wide range of tunable properties. Here,the authors describe the recent progress and challengesin the solution-chemistry approach to graphene nanos-tructures. This approach could not only lead to newmaterials with various well-defined properties, but also



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enable their production in large quantities. 154 Refer-ences.

• Graphene Filled Polymer Nanocomposites. ByR. Verdejo, M. M. Bernal, L. J. Romasanta andM. A. Lopez-Manchado,J. Mater. Chem.,21 (10),3301–3310 (2011).

AbstractGraphene has attracted the attention of a growingnumber of scientists from several disciplines dueto its remarkable physical properties and chemicalfunctionalisation capabilities. This article presents anoverview of graphene/polymer nanocomposites dis-cussing preparation, properties and potential applica-tions. The challenges and outlook of these emergingpolymer nanocomposites are also discussed. 87 Refer-ences.

• Assembly of Chemically Modified Graphene: Meth-ods and Applications. By Y. Xu and G. Shi,J. Mater. Chem.,21 (10), 3311–3323 (2011).

AbstractChemically modified graphenes (CMGs) are uniquebuilding blocks for “bottom up” nanotechnol-ogy because of their single-atom thickness, two-dimensional conjugated structure, and exceptionalphysical and chemical properties. Various hierarchi-cal structures and functional nanocomposites based onCMGs have been prepared by self-assembly.

Here, the authors reviewed the recent advances inthe assembly of CMGs in solution or at interfaces, anddemonstrate the wide application of the resulting mate-rials. 119 References.

• A Review of Chemical Vapour Deposition ofGraphene on Copper. By C. Mattevi, H. Kim andM. Chhowalla,J. Mater. Chem.,21 (10), 3324–3334(2011).

AbstractThe discovery of uniform deposition of high-qualitysingle layered graphene on copper has generated sig-nificant interest. That interest has been translated intorapid progress in terms of large area deposition of thin

films via transfer onto plastic and glass substrates. Theopto-electronic properties of the graphene thin filmsreveal that they are of very high quality with trans-mittance and conductance values of>90% and 30Ω/sq, both are comparable to the current state-of-the-art indium tin oxide transparent conductor.

In this Article, the authors provide a detailed andup to date description of the literature on the subject aswell as highlighting challenges that must be overcomefor the utilization of graphene deposited on copper sub-strates by chemical vapour deposition. 98 References.

• Chemical Doping of Grapheme. By H. Liu, Y. Liuand D. Zhu,J. Mater. Chem.,21 (10), 3335–3345(2011).

AbstractRecently, a lot of effort has been focused on improvingthe performance and exploring the electric propertiesof graphene. This article presents a summary of chem-ical doping of graphene aimed at tuning the electronicproperties of graphene. p-Type and n-type doping ofgraphene achieved through surface transfer doping orsubstitutional doping and their applications based ondoping are reviewed. Chemical doping for band gaptuning in graphene is also presented. It will be benefi-cial to designing high performance electronic devicesbased on chemically doped graphene. 153 References.

• Ultrahigh Density Data Storage based on OrganicMaterials with SPM Techniques. By Y. Ma, Y. Wenand Y. Song,J. Mater. Chem.,21 (11), 3522–3533(2011).

AbstractWith the ever-increasing demand of expansive stor-age capacity and the continuous miniaturization ofoptoelectronic device, ultrahigh density data storagehas attracted intensive research interest. In this arti-cle, recent progress on the developments of ultra-high density data storage based on organic materialsis summarized and discussed., The article especiallyfocuses on materials for data recording using scanningtunneling microscopy (STM), atom force microscopy(AFM), and scanning near-field microscopy (SNOM).The focus is placed on the rational design and synthesisof new organic recording media to realize and improve



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nanoscale data storage. In addition, an outlook in thisfield is also discussed. 96 References.

• The Oxidation of Aniline to Produce “Polyani-line”: A Process Yielding Many Different NanoscaleStructures. By H. D. Tran, J. M. D’Arcy, Y. Wang,P. J. Beltramo, V. A. Strong and R. B. Kaner,J. Mater. Chem.,21 (11), 3534–3550 (2011).

AbstractThe number of different nano- and micro-scale struc-tures produced from the chemical oxidation of anilineinto “polyaniline” is rivaled by few other organic mate-rials. Nanoscale structures such as fibers, tubes, alignedwires, flowers, spheres and hollow spheres, plates, andeven those resembling anatomical organs, insects, andsea animals have been observed for the products pro-duced when aniline is oxidized.

This article examines these different structuresand the small and subtle changes in reaction parame-ters that result in their formation. These changes canoften result in drastic differences in the polymer’snanoscale morphology.Because a nanomaterial’s prop-erties are highly dependent on the type of morphologyproduced, understanding polyaniline’s propensity forforming these structures is crucial towards tailoring thematerial for different applications as well as improvingits synthetic reproducibility. The different approachesto commonly observed polyaniline nanostructures arepresented in this article along with some of the highlydebated aspects of these processes. The article endswith an approach towards resolving some of these con-tentious issues and a perspective on where things areheaded in the years to come. 150 References.

• What Controls Triplet Exciton Transfer in OrganicSemiconductors? By A. Kohler and H. Bassler,J. Mater. Chem.,21 (12), 4003–4011 (2011).

AbstractDexter-type triplet transfer is a phenomenon that isubiquitous in the field of molecular electronics, andthat takes place at the interface of chemistry, physicsand biology. It may be considered as a correlated trans-fer of two charges, and thus, models originally devel-oped for charge transfer may be applied to describe

triplet transfer. In dilute fluid solutions, triplet trans-fer from a donor to an acceptor is well-understood andit has been described in terms of Marcus theory,i.e.

taking into account distortions in the molecule and itssurroundings. In amorphous thin films, that are usedfor organic semiconductor applications, the effects ofenergetic disorder prevail, and they need to be con-sidered for an appropriate description of triplet energytransfer.

Here, an overview on recent experimental and the-oretical work concerning a unified description of tripletenergy transfer, is presented. 57 References.

• Gold-Platinum Nanoparticles: Alloying and PhaseSegregation. By B. N. Wanjala, J. Luo, B. Fang,D. Mott and C.-J. Zhong,J. Mater. Chem.,21 (12),4012–4020 (2011).

AbstractThe ability to control nanoscale alloying and phasesegregation properties is important for the explo-ration of multimetallic nanoparticles for the designof advanced functional materials and catalysts. Thisreview highlights recent insights into the nanoscalephase properties of gold-platinum (AuPt) nanoparti-cles, which serves as an example to shine a light onthe importance of changes in physical and chemicalproperties in which nanoscale multimetallic materialsmay differ from their bulk counterparts. In contrast tothe wide miscibility gap well known for the bulk gold-platinum system, the bimetallic nanoparticles havebeen demonstrated to exist in phases ranging fromalloy, partial alloy, to phase segregation depending onthe preparation conditions, the bimetallic composition,and the supporting materials. For AuPt nanoparticlessupported on carbon materials, the nanoscale alloyingor phase segregation is shown to be controllable bythermal treatment temperatures, which is not only evi-denced by detailed analysis of the phase and surfaceproperties, but also supported by theoretical modelingbased on thermodynamic and density functional the-ory.

The understanding of the nanoscale phase proper-ties can be correlated with the electrocatalytic activi-ties for fuel cell reactions such as methanol oxidationreaction and oxygen reduction reaction. Implicationsof the new insights to designing and nanoengineering



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the phase properties of multimetallic nanoparticles andcatalysts are also briefly discussed. 32 References.

• Thin Film Metal Hydrides for Hydrogen Stor-age Applications. By A. Baldi and B. Dam,J. Mater. Chem.,21 (12), 4021–4026 (2011).

AbstractThin film technology is a powerful exploratory tech-nique in the search for advanced hydrogen-storagesystems. Thin films of metal hydrides allow one toperform high-throughput screening of large materialslibraries, discover new metastable phases inaccessibleby bulk preparation methods, and model the finite-sizeeffects occurring at the nanoscale. 41 References.

• Nanostructured Catalysts in Fuel Cells. By Y. Qiaoand C. M. Li,J. Mater. Chem.,21 (12), 4027–4036(2011).

AbstractFuel cells are promising green power sources with the-oretically zero pollution and broad applications. Oneof the most important challenges for fuel cells is tohave more cost-effective catalysts with high catalyticactivity. Nanoscience has stimulated extensive interestin nanostructured catalysts to significantly improve theenergy density, power density and operation reliabilitywhile greatly reducing the manufacturing expense. Inparticular, nanostructured materials play a critical rolein the catalysis of various innovative fuel cells, whichnot only possess high specific surface area and goodconductivity for low polarization, but also provideunique nanoporous structures and functional chemicalproperties for highly intrinsic electroactivity and excel-lent utilization.

The recent advances in nanostructured catalystsand supports are reviewed in this article. The rela-tionships between the nanostructures and electrocat-alytic performance and the catalysis mechanisms arediscussed. 110 References.

• Enhancement of the Thermoelectric Propertiesin Nanoscale and Nanostructured Materials. ByJ. R. Szczech, J. M. Higgins and S. Jin,J. Mater.Chem.,21 (12), 4037–4055 (2011).

AbstractThermoelectric materials can be used for solid statepower generation and heating/cooling applications.The figure of merit of thermoelectric materials, ZT,which determines their efficiency in a thermoelec-tric device, remains low for most conventional bulkmaterials. Nanoscale and nanostructured thermoelec-tric materials are promising for increasing ZT relativeto the bulk.

This review introduces the theory behind ther-moelectric materials and details the predicted anddemonstrated enhancements of ZT in nanoscale andnanostructured thermoelectric materials. The authorsdiscuss thin films and superlattices, nanowires andnanotubes, and nanocomposites, providing a ZTcomparison among various families of nanocompositematerials. They provide some perspectives regardingthe origin of enhanced ZT in nanoscale and nanostruc-tured materials and suggest some promising and fruit-ful research directions for achieving high ZT materialsfor practical applications. 149 References.

• Activation of Carbide-Derived Carbons: A Routeto Materials with Enhanced Gas and Energy Stor-age Properties. By M. Sevilla and R. Mokaya,J. Mater. Chem.,21 (13), 4727–4732 (2011).

AbstractThermal halogenation of a wide range of metal car-bides provides a simple route to a class of so-calledcarbide-derived carbon (CDC) materials. The poros-ity of the CDCs, which is mainly in the microporousregime, may be modulated by the choice of metal car-bide precursor and halogenation temperature. How-ever, although the pore size of CDCs can be fine-tunedby the choice of synthesis process, the maximum sur-face area achieved is only up to 2500 m2 g−1, whichlimits their use in gas storage or in electrochemicalcapacitor applications that require larger surface areas.

This article is focused on what has and can be doneto enhance the textural properties of CDCsvia furtherpost-synthesis treatments and the ramifications of suchmodifications on their gas/energy storage capacity. Themain developments in physical and chemical activationof CDCs and consequences on gas and energy storageare summarized. 56 References.



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• Multilayer Edge Molecular Electronics Devices: AReview. By P. Tyagi,J. Mater. Chem.,21 (13),4733–4742 (2011).

AbstractMolecular electronics devices have potential to minia-turize the computational devices down to few nmand can be highly versatile. The realization of anymolecular electronics device critically depends on themethods of connecting functional molecule(s) to elec-trical leads. This review mainly focuses on the recentlydeveloped versatile multilayer edge molecular elec-tronics device (MEMED) approach.

To produce MEMEDs molecular conduction chan-nels are bridged across the ultrathin insulator, along theexposed vertical edges of a tunnel junction. MEMEDcan be produced by widely available microfabricationtools. The tunnel junction used in a MEMED can haveany combination of metallic electrodes, and can becharacterized before establishing molecular conduc-tion channels. Besides the application in computationaldevices, MEMED design can also be used for biosens-ing by enabling the interaction between MEMED’sactive molecular channels with the target bio-analytes.75 References.

• Advanced Hydrogen Storage Alloys for Ni/MHRechargeable Batteries. By Y. Liu, H. Pan, M. Gaoand Q. Wang,J. Mater. Chem.,21 (13), 4743–4755(2011).

AbstractHydrogen storage alloys are of particular interest asa novel group in functional materials owing to theirpotential and practical applications in Ni/MH recharge-able batteries. This review is devoted to the specificalloy families developed for high-energy and high-power Ni/MH batteries in the last decades, especiallyfor EV, HEV and PHEV applications.

The scope of the work encompasses princi-ples of Ni/MH batteries, electrochemical hydrogenstorage thermodynamics and kinetics, prerequisitesfor hydrogen storage electrode alloys and recentadvances in hydrogen storage electrode alloys. Rareearth AB5-type alloys, Ti- and Zr-based AB2-typealloys, Mg-based amorphous/nanocrystalline alloys,rare earth-Mg–Ni-based alloys and Ti–V-based alloys

are highlighted. Additionally, the challenges met indeveloping advanced hydrogen storage alloys forNi/MH rechargeable batteries are pointed out and someresearch directions are suggested. 185 References.

• Chemistry and High Temperature Superconductiv-ity. By J. P. Attfield, J. Mater. Chem.,21 (13),4756–4764 (2011).

AbstractSeven distinct families of superconductors with criticaltemperatures at ambient pressure that equal or surpassthe historic 23K limit for Nb3Ge have been discoveredin the last 25 years. Each family is reviewed briefly andtheir common chemical features are discussed.

High temperature superconductors are distin-guished by having a high (≥50%) content ofnonmetallic elements and fall into two broad classes.‘Metal–nonmetal’ superconductors require a specificcombination of elements such as Cu–O and Fe–Aswhich give rise to the highest known Tc’s, probablythrough a magnetic pairing mechanism. ‘Nonmetal-bonded’ materials contain covalently bonded nonmetalanion networks and are BCS-like superconductors. Fit-ting an extreme value function to the distribution ofTc values for the known high- Tc families suggeststhat the probability of a newly discovered supercon-ductor family having maximum Tc > 100 K is∼0.1 to1%, decreasing to∼0.02 to 0.2% for room temperaturesuperconductivity. 45 References.

• Novel Rare-Earth-Free Tunable-Color-EmittingBCNO Phosphors. By W.-N. Wang, T. Ogi,Y. Kaihatsu, F. Iskandar and K. Okuyama,J. Mater. Chem.,21 (14), 5183–5189 (2011).

AbstractThe authors present a facile synthesis of novel, rare-earth (RE)-ion-free boron carbon oxynitride (BCNO)phosphors. The preparation method, chemical com-position, luminescent properties and emission mech-anisms, as well as current trends in BCNO phosphorsare reviewed.

The novel BCNO phosphors were synthesizedfrom inexpensive and environmentally friendly rawmaterials by a straightforward route using liquidprecursors at low temperatures under atmosphericpressure. The newly developed BCNO phosphors



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demonstrated tunable color emission, high quantumefficiency, and long-duration afterglow. The coloremission of these phosphors can be tuned across almostthe entire visible light spectrum by varying the molarratios of the raw materials. 48 References.

• Bio-Imaging, Detection and Analysis by usingNanostructures as SERS Substrates. By W. Xie,P. Qiu and C. Mao,J. Mater. Chem.,21 (14),5190–5202 (2011).

AbstractSurface-enhanced Raman scattering (SERS) is a phe-nomenon that occurs on nanoscale-roughed metallicsurface. The magnitude of the Raman scattering signalcan be greatly enhanced when the scatterer is placed inthe very close vicinity of the surface, which enablesthis phenomenon to be a highly sensitive analyticaltechnique. SERS inherits the general strongpoint ofconventional Raman spectroscopy and overcomes theinherently small cross section problem of a Ramanscattering. It is a sensitive and nondestructive spec-troscopic method for biological samples, and can beexploited either for the delivery of molecular structuralinformation or for the detection of trace levels of ana-lytes. Therefore, SERS has long been regarded as apowerful tool in biomedical research. Metallic nanos-tructure plays a key role in all the biomedical appli-cations of SERS because the enhanced Raman signalcan only be obtained on the surface of a finely dividedsubstrate.

This review focuses on progress made in the use ofSERS as an analytical technique in bio-imaging, anal-ysis and detection. Recent progress in the fabricationof SERS active nanostructures is also highlighted. 167References.

• Towards Printable Organic Thin Film Transistorbased Flash Memory Devices. By W. L. Leong,N. Mathews, B. Tan, S. Vaidyanathan, F. Dotz andS. Mhaisalkar,J. Mater. Chem.,21 (14), 5203–5214(2011).

AbstractThe implementation of plastic electronic solutions tolarge area displays, disposable sensor arrays, radio-frequency identification tags (RFIDs), and varioussmart packaging devices necessitate the development

of organic memories that are solution-processable andreadily integrated with the transistors for digital logic.

This article highlights recent research progressmade towards organic memory transistors based oncharge trapping and focuses on the principles andmaterials (namely, nanoparticles and polymer elec-trets) for these devices. The challenges and prospectsof charge trapping memories are also discussed. 66References.

• One-Dimensional Coordination Polymers: Com-plexity and Diversity in Structures, Properties, andApplications. By W. L. Leong and J. J. Vittal,Chem.Rev.,111(2), 688–764 (2011).

AbstractCrystal engineering of coordination polymers, whichinvolves self-assembly of organic ligands with appro-priate functional groups and metal ions with spe-cific directionality and functionality, is one of thefacile routes to produce materials of technologi-cal importance. The non-molecular compounds inwhich the basic building blocks containing metalions and organic ligands assemble infinitely lead-ing to one-, two-, and three-dimensional networks,are commonly known as coordination polymers ormetal-organic frameworks (MOFs). Of these one-dimensional coordination polymer (1D CP), being thesimplest topological type of coordination array, isfound to be ubiquitous in nature. The relative simplic-ity of the 1D chains and their ease of formation by self-assembly allow us to incorporate functional propertiesat the metal centers or in the backbone of the organiclinkers very easily to develop strategies for engineeringmultifunctional polymeric materials.

This review focuses on the recent progress made onthe linear and zigzag 1D CPs, emphasizing on unusualpacking and interesting properties with selected exam-ples from the literature. 473 References.

• Block Copolymer based Composition and Morphol-ogy Control in Nanostructured Hybrid Materials forEnergy Conversion and Storage: Solar Cells, Batter-ies, and Fuel Cells. By M. C. Orilall and U. Wiesner,Chem. Soc. Rev.,40 (2), 520–535 (2011).



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AbstractThis review highlights block copolymers as an emerg-ing and powerful yet affordable tool to structure-directnano-materials with precise control over structuraldimensions, composition and spatial arrangement ofmaterials in composites for uses in photovoltaics,batteries and fuel cells. In each case, insights areprovided into the various underlying fundamentalchemical, thermodynamic and kinetic formation prin-ciples enabling general and relatively inexpensive wet-polymer chemistry methodologies for the efficientcreation of multiscale functional materials. Exam-ples include nanostructured ceramics, ceramic–carboncomposites, ceramic–carbon–metal composites andmetals with morphologies ranging from hexagonallyarranged cylinders to three-dimensional bi-continuouscubic networks. 68 References.

• Progress on lanthanide-based organic–inorganic hybrid phosphors. By L. D. Carlos,R. A. S. Ferreira, V. de Zea Bermudez,B. Julian-Lopez and P. Escribano,Chem. Soc. Rev.,40 (2), 536–549 (2011).

AbstractResearch on organic–inorganic hybrid materials con-taining trivalent lanthanide ions (Ln3+) is a very activefield that has rapidly shifted in the last couple ofyears to the development of eco-friendly, versatile andmultifunctional systems, stimulated by the challengingrequirements of technological applications spanningdomains as diverse as optics, environment, energy, andbiomedicine. This article offers a general overview ofthe myriad of advanced Ln3+-based organic–inorganichybrid materials recently synthesised, which may beviewed as a major innovation in areas of phosphors,lighting, integrated optics and optical telecommunica-tions, solar cells, and biomedicine. 61 References.

• Recent Development and Application of Li4Ti5O12

as Anode Material of Lithium Ion Battery. ByT.-F. Yi, L.-J. Jiang, J. Shu, C. –B. Yue, R.-S. Zhuand H.-B. Qiao, J. Phys. Chem. Solids, 71 (9),1236–1242 (2010).

AbstractLithium-ion batteries with both high power and highenergy density are one of the promising power sources

for electric devices, especially for electric vehicles(EV) and other portable electric devices. One of thechallenges is to improve the safety and electrochemi-cal performance of lithium ion batteries anode mate-rials. Li4Ti5O12 (LTO) has been accepted as a novelanode material of power lithium ion battery instead ofcarbon because it can release lithium ions repeatedlyfor recharging and quickly for high current. However,Li4Ti5O12 has an insulating character due to the elec-tronic structure characterized by empty Ti 3d-states,and this might result in the insufficient applications ofLTO at high current discharge rate before any materialsmodifications.

This review focuses first on the present status ofLTO including the synthesized method, doping, surfacemodification, application and theoretical calculation,then on its near future development. 85 References.

• Nanomaterials: Applications in Cancer Imaging andTherapy. By J. A. Barreto, W. O’Malley, M. Kubeil,B. Graham, H. Stephan and L. Spiccia,Adv. Mater.,23 (12) H18–H40 (2011).

AbstractThe application of nanomaterials (NMs) inbiomedicine is increasing rapidly and offers excellentprospects for the development of new non-invasivestrategies for the diagnosis and treatment of cancer.In this review, the authors provide a brief descriptionof cancer pathology and the characteristics that areimportant for tumor-targeted NM design, followed byan overview of the different types of NMs exploredto date, covering synthetic aspects and approachesexplored for their application in uni-modal and multi-modal imaging, diagnosis and therapy.

Significant synthetic advances now allow for thepreparation of NMs with highly controlled geometry,surface charge, physicochemical properties, and thedecoration of their surfaces with polymers and bioac-tive molecules in order to improve biocompatibilityand to achieve active targeting. This is stimulatingthe development of a diverse range of nanometer-sized objects that can recognize cancer tissue, enablingvisualization of tumors, delivery of anti-cancer drugsand/or the destruction of tumors by different therapeu-tic techniques. 396 References.



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• Hyaluronic Acid Hydrogels for Biomedical Appli-cations. By J. A. Burdick and G. D. Prestwich,Adv.Mater.,23 (12) H41–H56 (2011).

AbstractHyaluronic acid (HA), an immunoneutral polysaccha-ride that is ubiquitous in the human body, is crucialfor many cellular and tissue functions and has beenin clinical use for over thirty years. When chemicallymodified, HA can be transformed into many physicalforms—viscoelastic solutions, soft or stiff hydrogels,electrospun fibers, non-woven meshes, macroporousand fibrillar sponges, flexible sheets, and nanopartic-ulate fluids—for use in a range of preclinical andclinical settings. Many of these forms are derivedfrom the chemical crosslinking of pendant reactivegroups by addition/condensation chemistry or by rad-ical polymerization. Clinical products for cell therapyand regenerative medicine require crosslinking chem-istry that is compatible with the encapsulation of cellsand injection into tissues. Moreover, an injectable clin-ical biomaterial must meet marketing, regulatory, andfinancial constraints to provide affordable products thatcan be approved, deployed to the clinic, and used byphysicians. Many HA-derived hydrogels meet thesecriteria, and can deliver cells and therapeutic agents fortissue repair and regeneration.

This review covers both basic concepts and recentadvances in the development of HA-based hydrogelsfor biomedical applications. 137 References.

• Biomimetic Smart Interface Materials for BiologicalApplications. By T. Sun and G. Qing,Adv. Mater.,23 (12) H57–H77 (2011).

AbstractControlling the surface chemical and physical proper-ties of materials and modulating the interfacial behav-iors of biological entities, e.g., cells and biomolecules,are central tasks in the study of biomaterials. Inthis context, smart polymer interface materials haverecently attracted much interest in bio-related appli-cations and have broad prospects due to the excel-lent controllability of their surface properties byexternal stimuli. Among such materials, poly (N-isopropylacrylamide) and its copolymer films are

especially attractive due to their reversible hydrogen-bonding-mediated reversible phase transition, whichmimics natural biological processes. This platform ispromising for tuning surface properties or to introducenovel biofunctionalities via copolymerization with var-ious functional units and/or combination with othermaterials.

Important progress in this field in recent years ishighlighted. 148 References.

• Emerging Transparent Electrodes based on ThinFilms of Carbon Nanotubes, Graphene, and MetallicNanostructures. By D. S. Hecht, L. Hu and G. Irvin,Adv. Mater.,23 (13) 1482–1513 (2011).

AbstractTransparent electrodes are a necessary component inmany modern devices such as touch screens, LCDs,OLEDs, and solar cells, all of which are growing indemand. Traditionally, this role has been well servedby doped metal oxides, the most common of whichis indium tin oxide, or ITO. Recently, advances innano-materials research have opened the door for othertransparent conductive materials, each with uniqueproperties. These include carbon nanotubes (CNTs),graphene, metal nanowires, and printable metal grids.

This review will explore the materials propertiesof transparent conductors, covering traditional metaloxides and conductive polymers initially, but with afocus on current developments in nano-material coat-ings. Electronic, optical, and mechanical properties ofeach material will be discussed, as well as suitabilityfor various applications. 299 References.

• Single Molecule Electronic Devices. By H. Song,M. A. Reed and T. Lee,Adv. Mater., 23 (13)1583–1608 (2011).

AbstractSingle molecule electronic devices in which individ-ual molecules are utilized as active electronic compo-nents constitute a promising approach for the ultimateminiaturization and integration of electronic devices innanotechnology through the bottom-up strategy. Thus,the ability to understand, control, and exploit chargetransport at the level of single molecules has becomea long-standing desire of scientists and engineers from



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different disciplines for various potential device appli-cations. Indeed, a study on charge transport throughsingle molecules attached to metallic electrodes is avery challenging task, but rapid advances have beenmade in recent years.

This review focuses on experimental aspects ofelectronic devices made with single molecules, with aprimary focus on the characterization and manipulationof charge transport in this regime. 210 References.

• Assemblies of Functional Peptides and Their Appli-cations in Building Blocks for Biosensors. ByR. de la Rica, C. Pejoux and H. Matsui,Adv. Funct.Mater., 22 (6) 1018–1026 (2011).

AbstractThis article highlights the authors’ recent applicationsof functional peptide nanotubes, self-assembled fromshort peptides with recognition elements, as buildingblocks to develop sensors.

Peptide nanotubes with high aspect ratios areexcellent building blocks for a directed assem-bly into device configurations, and their combinedstructures with nanometric diameters and micro-metric lengths enables to bridge the “nanoworld”and the “microworld”. When the peptide-nanotube-based biosensors, which incorporate molecular recog-nition units, apply alternating current probes to detectimpedance signals, the peptide nanotubes behave asexcellent building blocks of the transducer for thedetection of target analytes such as pathogens, cells,and heavey metal ions with high specificity. In somesensor configurations, the electric signal can be ampli-fied by coupling them with ion-specific mineralizationvia molecular recognition of peptides. In general thedetection limit of peptide nanotube chips sensors isvery low and the dynamic range of detection can bewidened by improved device designs. 38 References.

• Self-Assembled Nanometer-Scale Magnetic Net-works on Surfaces: Fundamental Interactionsand Functional Properties. By C. Carbone,S. Gardonio, P. Moras, S. Lounis, M. Heide,G. Bihlmayer, N. Atodiresei, P. H. Dederichs,S. Blugel, S. Vlaic, A. Lehnert, S. Ouazi,S. Rusponi, H. Brune, J. Honolka, A. Enders,K. Kern, S. Stepanow, C. Krull, T. Balashov,

A. Mugarza and P. Gambardella,Adv. Funct. Mater.,22 (7) 1212–1228 (2011).

AbstractNanomagnets of controlled size, organized into reg-ular patterns open new perspectives in the fields ofnanoelectronics, spintronics, and quantum computa-tion. Self-assembling processes on various types ofsubstrates allow designing fine-structured architecturesand tuning of their magnetic properties.

Here, starting from a description of fundamen-tal magnetic interactions at the nanoscale, the authorsreview recent experimental approaches to fabricatezero-, one-, and two-dimensional magnetic parti-cle arrays with dimensions reduced to the atomiclimit and unprecedented areal density. They describesystems composed of individual magnetic atoms,metal-organic networks, metal wires, and bimetallicparticles, as well as strategies to control their mag-netic moment, anisotropy, and temperature-dependentmagnetic behavior. The investigation of self-assembledsub-nanometer magnetic particles leads to significantprogress in the design of fundamental and functionalaspects, mutual interactions among the magnetic units,and their coupling with the environment. 81 Refer-ences.

• Surface-Confined Self-Assembly of Di-carbonitrilePolyphenyls. By S. Klyatskaya, F. Klappenberger,U. Schlickum, D. Kuhne, M. Marschall, J.Reichert,R. Decker, W. Krenner, G. Zoppellaro, H. Brune,J. V. Barth and M. Ruben,Adv. Funct. Mater.,22 (7)1230–1240 (2011).

AbstractThis Article reports on the controlled formation andstructure-functionality aspects of vacuum-depositedself-assembled organic and metal-organic networksat metal surfaces using ditopic linear and nonlinearmolecular bricks, namely di-carbonitrile polyphenyls.

Surface confined supramolecular organization oflinear aromatic molecules leads to a fascinating varietyof open networks. Moreover, cobalt-directed assem-bly of the same linear linkers reveals highly regu-lar, open honeycomb networks with tunable pore sizesrepresenting versatile templates for the organization



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of molecular guests or metal clusters and the con-trol of supramolecular dynamers. In addition, the 2D(two dimensional) nanopore organic networks act asarrays of quantum corrals exhibiting confinement ofthe surface-electronic states of the metallic substrate. Areduction of the linker symmetry leads to the formationof disordered, glassy coordination networks, whichrepresent a structural model for amorphous materials.60 References.

• Selective and Responsive Nanoreactors. ByK. Renggli, P. Baumann, K. Langowska, O. Onaca,N. Bruns and W. Meier,Adv. Funct. Mater.,22 (7)1241–1259 (2011).

AbstractChemical reactions can be confined to nanoscalecompartments by encapsulating catalysts in hollownano-objects. Such reaction compartments effectivelybecome nanoreactors when substrate and product areexchanged between bulk solution and cavity. A keyissue, thereby, is control of shell permeability. Nanore-actors exhibit selectivity and responsiveness if theirshells discriminate among molecules and if access canbe modulated by external triggers.

Here, the authors review natural nanoreactorsthat include protein-based bacterial microcompart-ments, protein cages, and viruses. Artificial nanore-actors based on dendrimers, layer-by-layer capsules,and amphiphilic block copolymer polymersomes arealso discussed. Selectivity in these nanoreactors iseither due to intrinsic reactor-shell semipermeabil-ity or can be engineered using smart polymersto gate the reactors. Moreover, a rich repertoireof pores and channels are already provided innature, e.g., in protein-based nanoreactors or in trans-membrane channel proteins. The latter can be recon-stituted in polymersomes, resulting in gated vesicles.Nanoreactors hold promise for applications rangingfrom selective and size-constrained organic synthe-sis to biomedical advances (e.g., artificial organelles,biosensing) and as analytical tools to study reactionmechanisms. 202 References.

• Self-Assembly and Shape Morphology of LiquidCrystalline Gold Metamaterials. By M. Draper,I. M. Saez, S. J. Cowling, P. Gai, B. Heinrich,

B. Donnio, D. Guillon and J. W. Goodby,Adv.Funct. Mater.,22 (7) 1260–1278 (2011).

AbstractGold nanoparticles offer the possibility of creatingmetamaterials; however, such nanoparticles are notparticularly stable. Conversely, liquid crystals offerthe possibility of creating self-organizing and self-assembling materials, which can be designed to berelatively stable. Potentially, combining these two con-cepts could provide materials that can be induced toassemble in a controlled way and that would haveunique optical properties.

This article describes some of the groundworkmade in the preparation of stable liquid-crystallinemetamaterials and the investigation of their structuresand physical properties. In particular, spherically sub-stituted materials are found to be deformed into tac-toids with anisotropic properties, most notably theirdielectric anisotropies. 68 References.

• Non-conventional Processing and Post-processingMethods for the Nanostructuring of ConjugatedMaterials for Organic Electronics. By G. De Luca,W. Pisula, D. Credgington, E. Treossi, O. Fenwick,G. M. Lazzerini, R. Dabirian, E. Orgiu, A. Liscio,V. Palermo, K. Mullen, F. Cacialli and P. Samorı,Adv. Funct. Mater.,22 (7) 1279–1295 (2011).

AbstractIn the search for new ways to combine the appealingsimplicity of solution processing methods and the needfor a high performance of the active layer of organic(opto) electronic devices, the possibilities given by thejoint use of well-established casting techniques andpost-treatment procedures are explored, as well as newand unconventional deposition protocols to tailor self-assembled architectures with a high degree of order atdifferent length scales, from the sub-nanometer up tothe macroscopic scale. In fact, even the same organicmolecule can give rise to different molecular architec-tures which, in turn, may offer the possibility to exploita large variety of new functionalities of the depositedmaterials, paving the way towards the fabrication ofmultifunctional organic-based devices. 68 References.



• Self-Assembly at Different Length Scales:Polyphilic Star-Branched Liquid Crystals andMiktoarm Star Copolymers. By G. Ungar,C. Tschierske, V. Abetz, R. Holyst, M. A. Bates,F. Liu, M. Prehm, R. Kieffer, X. Zeng, M. Walker,B. Glettner and A. Zywocinski,Adv. Funct. Mater.,22 (7) 1296–1323 (2011).

AbstractThe diversity of phase morphologies observed recentlyin star-branched liquid-crystalline and polymeric com-pounds containing at least three immiscible segmentsis reviewed.

Bolaamphiphiles and facial amphiphiles with rod-like aromatic cores, two end-groups, and one (T-shape)or two (X-shape) chains attached laterally to the core,form numerous honeycomblike liquid-crystal phases,as well as a variety of novel lamellar and 3D-orderedmesophases. Molecular self-organization is describedin bulk phases and in thin films on solid and liq-uid surfaces, as well as in Langmuir–Blodgett films.The remarkably reversible formation of mono- and tri-layer films is highlighted. In the bulk, T-shaped “rod–coil” molecules without appended end-groups formpredominantly lamellar phases if the core is a straightrod, but the bent-core variety forms hexagonal hon-eycombs. Furthermore, self-assembly of “Janus”-typemolecules, is discussed. Also covered is the diversityof morphologies observed in miktoarm star terpoly-mers, i.e., polymers with three different and incom-patible arms of well defined lengths. Similarities anddifferences are highlighted between the liquid-crystalmorphologies on the 3–15 nm scale and the polymermorphologies on the scale of 10–100 nm. A separatesection is dedicated to computer simulations of suchsystems, particularly those using dissipative particleand molecular dynamics. Of special interest are therecently synthesised X-shaped tetraphilic molecules,where two different and incompatible side-chains areattached at opposite sides of the rodlike core. Thetendency for their phase separation produces liquid-crystal honeycombs with cells of different composi-tions that can be represented as a plane paved with

different colored tiles. The independent variation ofchain length and “color” creates the potential fordeveloping a considerable range of complex new 2Dand 3D soft nanostructures. Analogous X-shaped rod–coil compounds with unequal side groups are also ofconsiderable interest, forming tubular lyotropic struc-tures capable of confining strings of guest molecules.182 References.

• The Challenge of Unconventional Superconductiv-ity. By M. R. Norman,Science,332(6026), 196–200(2011).

AbstractDuring the past few decades, several new classes ofsuperconductors have been discovered that do notappear to be related to traditional superconductors.The source of the superconductivity of these materi-als is likely different from the electron-ion interactionsthat are at the heart of conventional superconductivity.Developing a rigorous theory for any of these classesof materials has proven to be a difficult challenge andwill remain one of the major problems in physics in thedecades to come. 66 References.

• The Electron-Pairing Mechanism of Iron-basedSuperconductors. By F. Wang and D.-H. Lee,Sci-ence,332(6026), 200–204 (2011).

AbstractThe past three years have witnessed the discovery ofa series of novel high-temperature superconductors.Trailing behind the cuprates, these iron-based com-pounds are the second–highest-temperature supercon-ducting material family known to date. Despite themarked differences in the chemical composition, thesematerials share many properties with the cuprates andoffer the hope of finally unveiling the secret of high-temperature superconductivity.

The main theme of this review is the electron-pairing mechanism responsible for their superconduc-tivity, and discuss the progress in this young field andpoint out the open issues. 63 References.


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Forthcoming Conferences

18th International Conference on Solid State Ionics, July 3–8, 2011, Warsaw, Poland

TopicsTheory, modelling and kinetics-Techniques-Oxide Ion Conductors-Mixed Conductors-New Materials-Fuel Cells-Electrocatalysis-Sensors-Proton Conductors-Nanoionics-Glasses-Lithium Batteries-Polymer Electrolytes-EnergyStorage-Ionic Liquids.Workshop for young scientist will be organized at Faculty ofPhysics, Warsaw University of Tech.WorkshopWorkshop for young scientist will be organized at the Faculty of Physics, Warsaw University of Tech.,Warsaw.

Confirmed Invited SpeakersMaria Forsyth (Australia), Clare Grey (USA/UK), Saiful Islam (UK), Rainer Waser (Germany), Harumi Yokokawa(Japan) and Christian Masquelier (Amiens, France).Website:http://ssi-18.net/

19th Annual International Conference on Composites or Nano Engineering (ICCE-19),July 24–30, 2011, Shanghai, China

Major Topics of ICCE-19Aging, Flammability; Bio-Composites; Mathematical Modeling ; Chemistry of Materials; Coatings and Wear;Metal Matrix Composites; Ceramics Composites; Micromechanics; Packaging Barrier; Electronic/Magnetic Meta-materials; Particulate Composites; Engineering Science and Structures; Powder Metallurgy; Textile Composites;Functionally Graded Materials; Impact Engineering; Vibration; Infrastructures; Composites; Computational Mate-rials; Durability; Natural Fibers; Processing; Biology; Physics of Materials.

Major Symposia of ICCE-19Metals Research; Nano Bio Materials; Nano Devices and Actuators; Inorganic Nanowires; Nano-Fabrication;NanoLithography; Nanosensor; Magnetic Materials; Thin Films; Surface-Coating; Processing/Characterization;Durabilty of Composites.Deadline for Submission of Short Paper: March,24,2011;Deadline for Full Length Paper: July,17,2011Website:http://www.icce-nano.org/

The 6th Conference of the Asian Consortium on ComputationalMaterials Science (ACCMS-6),6–9 Sept., 2011, Singapore

The 6th Conference of the Asian Consortium on ComputationalMaterials Science (ACCMS-6), will be held inSingapore, from 6 to 9 September 2011. The conference is jointly organized by the National University of Singa-pore, Institute of Advanced Studies at the Nanyang Technological University, and Materials Research Society ofSingapore.

The ACCMS was established in 2000 in order to nurture and promote research and development activities incomputational materials in Asian countries. The biennial ACCMS conference has become an international event forexchanging and archiving knowledge on the development of advanced computational methodology and its stronglink to material science and engineering applications. Theprevious ACCMS conferences were successfully held



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in India (Bangalore 2001), Russia (Novosibirsk, 2004), China (Beijing, 2005), Korea (Seoul, 2007) and Vietnam(Hanoi, 2009).

Computational Materials Science (CMS) has emerged as a distinct multidisciplinary branch of science andcomputer modeling and simulation is playing an increasingly important role in materials science research.ACCMS-6 will provide a platform for computational materials scientists in Asian and world to present their recentresults on research and development in CMS. The scope of the conference ranges from fundamental computationalmethodology (density functional theory and beyond, quantum mechanical based interatomic potentials, moleculardynamic and Monte-Carlo simulation of thermodynamic and kinetic properties at large length and time scales,phase field method of micro-structural simulation, etc.) toits industrial applications of different materials proper-ties.

All computational materials scientists, including graduate students, from Asia as well as in other parts of theworld are invited to participate in this conference. In addition to the three-day conference (7-9 September) whichconsists of plenary sessions, invited talks, contributed talks and poster presentation, pre-conference short courseswill be held on 6 September to introduce new computational methods and/or emerging computational trends tobeginners and those who may be interested in exploring new methods in their research.

Website:http://www.mrs.org.sg/accms6/For further information, please contact, Prof. Yuan Ping Feng, Co-Chair of ACCMS-6Tel: (65) 6516 2960;E-mail: [email protected] Miss Eileen So, Secretariat of ACCMS-6, DID: (65) 6874 1176; HP: (65) 8223 9845Email: [email protected]

The 7th International Conference on Porous Metals and Metallic Foams [MetFoam2011],Sep., 18–21, 2011, Busan, Korea

The conference will cover the following topics (but will notbe limited to):

• Physics of foaming, pore nucleation, pore growth and coalescence, foam stabilization• Techniques for making foams and other cellular metals, effect of processing parameters on the structure and

properties• Morphological and microstructural characterization at different size scales• Property profiles in relation with porous structure• Modelling of structure, structure development and relatesproperties• Secondary operations (joining, coating, machining, shaping, etc.)• Challenging applications and case studies including component design criteria• Porous biomaterials and nanoporous structures

Key dates: Submission of Abstract: April 15, 2011; red Notification to Authors: April 30, 2011; EarlyRegistration: May 31, 2011; Submission of Manuscript: September 18, 2011. For details, see the Web-site: www.metfoam2011.org

The 7th International Symposium on ‘Novel Materials and their Synthesis’,11–14, October 2011, Shanghai, China

For further information, please contact, Prof. Yuping Wu, Chemistry Dept.,New energy and Mater. Lab., Fudan Univ., Shanghai, 200 433, China.E-mail: [email protected]


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International Conference on Advanced Electromaterials (ICAE 2011)Nov., 7 to 10, 2011, Jeju, Korea

The ICAE 2011 is intended to provide an open forum to all participants with an opportunity to present the latestimportant findings in research activities and to discuss andshare them with experts and renowned scholars fromall over the world. It consists of 14 symposia in the field of electrical and electronic materials such as semicon-ductors, electronic ceramics, high voltage technology andinsulating materials, sensors, displays, nano-materialsand devices, and energy materials. In these symposiums, stimulating lectures and presentations by distinguishedspeakers from all over the world are planned for the ICAE 2011. In addition to the professional exchange of ideas,it will be a place to meet friends who share common research objectives and to have chances for further co-workthat may result in mutual achievements. Jeju, the venue of the ICAE 2011 is a beautiful volcanic resort island.Symposium Title and the Organizer:

(1) Nanostructured Materials for Sensor Applications (SE)Organizer: Dr. Seok-Jin Yoon (KIST, Korea, [email protected])

(2) Advanced Materials for Energy Conversion: fuel cell andsolar cell (EC)Organizer: Dr. Tae-Hoon Lim (KIST, Korea, [email protected])

(3) Energy Storage Materials (ES)Organizer: Dr. Hyun-Soo Kim (KERI, Korea, [email protected])

(4) Nanostructured Materials for Energy Devices (ED)Organizer: Dr. Eun Dong Kim (KERI, Korea, [email protected])

(5) Emerging Nano-based Device Technologies (ND)Organizer: Dr. Kamran Eshraghian (Chungbuk Nat’l Univ., Korea, [email protected]

(6) Ferroelectric, Piezoelectric Materials and Device Applications (FM)Organizer: Prof. Jae-Shin Lee (University of Ulsan, Korea,[email protected])

(7) Superconducting and Magnetic Materials and Devices (SM)Organizer: Prof. Sang-Heon Lee (Sunmoon Univ., Korea, [email protected])

(8) Thin Film Processing and Devices (TF)Organizer: Prof. Soon-Gil Yoon (Chungnam Nat’l Univ., Korea, [email protected])

(9) Advanced Insulating Materials and Condition Monitoring Diagnosis for HVPower Apparatus (HV)Organizer: Dr. Sang-Jin Kim (KEPCO KDN, Korea, [email protected])

(10) LED & OLED Lighting Technology (LT)Organizer: Sung-Jin Park (University of Illinois at Urbana-Champaign, USA, [email protected])

(11) Nanoscale Interface Devices and Materials for OrganicElectronics (OE)Organizer: Prof. Hoon-Kyu Shin (POSTECH, Korea, [email protected])

(12) Flexible and Printable Electronic Materials and Devices (FE)Organizer: Dr. Byoung-Gon Yu (ETRI, Korea, [email protected])

(13) Advanced Technology for LEDs (LE)Organizer: Prof. Ja-Soon Jang (Yeungnam Univ., Korea, [email protected])

(14) Thermal Management Materials, Devices, Packages, andProcessing Technologies (TM)Organizer: Dr. Hyo-Tae Kim (KICET, Korea, [email protected])



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Important DatesAbstract Submission:May 15, 2011; AcceptanceNotice:June 30, 2011; Early Registration: July 15, 2011; ManuscriptSubmission:November 7, 2011Homepage:www.icae.krConference Chairman:Dae-Hee Paek (Wonkwang University)Conference Secretariat:For registration & inquires: ICAE2011 Secretariat:Tel: +82-70-8222-3371;Mobile: +82-10-9156-3571;Fax: +82-2-3412-8723;E-mail: [email protected]

Materials Education & Research in Singapore

There are two Universities and several Research Institutes in Singapore involved in teaching,research and development in the broad area of Materials Science, Engineering and Technology.These are listed below along with the Websites and provide information on the available coursesand opportunities for undergraduate, graduate and post doctoral research. They also entertainqueries regarding openings for Research Scientists and Faculty positions.

National University of Singapore: www.nus.edu.sg

Nanyang Technological University: www.ntu.edu.sg

Institute of Materials Research and Engineering (IMRE): www.imre.a-star.edu.sg

Institute of Microelectronics (IME): www.ime.a-star.edu.sg

Data Storage Institute: www.dsi.a-star.edu.sg

Institute of Chemical & Engineering Sciences: www.ices.a-star.edu.sg

Institute of High Performance Computing: www.ihpc.a-star.edu.sg

Singapore Institute of Manufacturing Technology: www.SIMTech.a-star.edu.sg

Institute of Bioengineering and Nanotechnology (IBN): www.ibn.a-star.edu.sg


Volume 6• No.1• July–Sept., 2011 MRS-S OUTLOOKIn

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INVITATION

MRS-S members are welcome tocontribute to ‘MRS-S OUTLOOK’

• To suggest topics and prospective author(s) for ‘thematic’ articles pertaining tothe areas of materials science, engineering and technology. These will be ofgeneral interest to the students, teachers as well as active researchers. Thesecan be 10–15 pages (A4-size, single spaced) with figures, tables and selectreferences.

• To contribute reports on the recently held conferences and information on theforthcoming conferences.

• To contribute ‘Highlights from Recent Literature’ in the areas of materialsscience, engineering and technology. These must pertain to the past two years,and be of general interest to non-specialists, students, teachers as well asactive researchers. Each ‘Highlight’ must not exceed 250–300 words, includ-ing reference(s). Contributing author(s) and e-mail address(es) will be includedunder each ‘Highlight’.

• To contribute information about the recent awards and distinctions conferredon the MRS-S members.

• To contribute ‘Letters to the Editor’. They may be edited for brevity, clarity andavailable space, and the author(s) will be informed.

Information on the above aspects may be communicated to the Editor:

Dr. G.V. Subba RaoE-mail: [email protected]

The Editorial Board of ‘MRS-S OUTLOOK’ reserves the right toinclude or not any of the submitted contributions.

Design & Typeset byResearch Publishing ServicesE-mail:[email protected]


Documents

mrs-fcv6n1 draft.qxd 7/19/2011 10:04 AM Page 1mrs.org.sg/outlook/MRS-S-OUTLOOK Vol6 No1_Final.pdf · The method works with the four differ- ... their widespread technological application