1. Graphene and other 2D material Introduction and overview
Prof Ian Kinloch Professor of Materials Science #GrapheneWeek
2. Graphene and other 2-D materials: Introduction and overview
Prof. Ian Kinloch Professor of Materials Science
[email protected]
3. My research EPSRC Challenging Engineering Fellow in Graphene
Production Carbon: Graphene, Nanotubes and Fibre Related 2D
materials Processing Dispersion Rheology Architecture control
Applications Electrochemical power storage Matrix modifiers Matrix
reinforcement -1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 -4.0x10 -6
-3.0x10 -6 -2.0x10 -6 -1.0x10 -6 0.0 1.0x10 -6 monolayer no defects
bilayer multi-layer (graphite) Current/radius/(A/cm) V vs Ag/AgCl
(V) WithProf. Young&Dryfe
4. Overview Graphene Structure Properties Not all graphene is
the same Production Applications Beyond graphene
5. The sp2 carbon family Graphene is imensional Buckyballs
Carbon Nanotubes Graphite A. K. Geim, K. S. Novoselov Nat Mater
2007, 6, 183.
6. Graphene properties Morphological Thinnest imaginable
material one atom Highest surface area 2630 m2/g Transparent to
light (97.7 %) Mechanical Stiffness = 1 TPa Strength = 130 GPa
Electrical and thermal Record thermal conductivity (6000 W/m/K)
Highest current density at room temp (million times of that in
copper) Highest intrinsic mobility (100 times more than Si)
Lightest charge carrier (Dirac fermions) Longest mean free path at
room temp (microns) Chemical Relatively easily functionalised
Processable Barrier Impervious to even He but potentially
controlled porosity.
7. Graphene in reality Monolayer Bilayer Trilayer 10 layer
GraphiteGraphene oxide Known since 1850s, 25 to 30 % O Can be
reduced Standards & techniques to identify these materials etc
need work and input from stakeholders. Flake length Surface
chemistry
8. The challenge V. Palmero et al., 2D Materials,
Submitted.
9. Overview Graphene Structure Properties Not all graphene is
the same Production Applications Beyond graphene
10. Production by removing elements from a large starting
material. Assembly of a nanostructure from smaller elements. How to
make nanomaterials
11. Novoselov et al, Nature, 490, 2012 Routes to graphene:
flakes and films
12. How to make GRAPHENE?
13. Electrochemical exfoliation of graphene Few layer graphene
on the gram scale WO2012120264-A1, three others pending filed
Cooper et al. Carbon, 66, 340-350, 2014 Abdelkader et al. ACS
Applied Mat & Sci, 2014
14. Video accelerated by 8 times speed
15. Graphene Oxide The production for GO is well established
and based on the Hummers method: Natural flake graphite + KNO3 (4.5
g) in concentrated sulfuric acid KMnO4 was added over 70 mins and
left for 7 days Disperse mixture into H2SO4 in water + hydrogen
peroxide and left overnight. The structural model for GO is still
under debate, typically it is given as:
Roukeetal.,Ang.Chemie.2011,50(14) The graphene produced is
hydrophilic and highly functionalised but low conductivity.
16. CVD on copper
17. A few example producers. (including plant and by all means
not exhaustive)
18. Overview Graphene Structure Properties Not all graphene is
the same Production Applications Beyond graphene
19. A key benefit, especially in the near term, is
multi-functionality, e.g. in OLED packing it is transparent, an
oxygen barrier, flexible, and conductive. Of course, the big
transformative application is probably not yet on the list!
Medicine Sensors, delivery
20. Applications: Composites & coatings
21. Potential of graphene: composites
22. Epoxy/Graphene nanoplatelet 25 micron diameter particles,
pc = 3 wt% 5 micron diameter particles, pc = 4 wt% Kinloch, Young
et al
23. 0 0.1 0.2 0.3 0.4 0.5 0.6 0 1 2 3 4 5 6 7 8 9
Thermalconductivity(Wm-1K-1) Wt % Thermal conductivity by laser
flash Kinloch, Young et al
24. PLAY YOUR BEST WITH GRAPHENE
25. Structural reinforcement in engineering polymers Thickness
1 layer = 1 TPa Modulus Layers Optimum 4-6 layers Diameter Minimum
length is ~ 3 mm for stress transfer Surface chemistry Balance
between performance and aggregation? Random alignment =8/15
DESIGNRULES CF/GF Hybrids Additive manufacture Injection moulded
components
27. Selective Membranes for purification
Nairetal.,Science,2012
28. Applications: Energy
29. Energy: Graphene 200 F/g super capacitor Abdelkader,
Kinloch, Dryfe, ACS Nano 2014 2 m 2032 COIN CELL Feng et al.
30. Energy generation: Thermoelectrics
Figureofmerit(higherbetter) Freer, Kinloch et al., App. Mat &
Interfaces, Accepted
31. Applications: Electronics
32. Graphene electronics high frequency FETs IBM produced
graphene FETs on a 2 wafer Frequency of 100 GHz for graphene
compared to ~40 GHz for silicon. Graphene has no band gap so poor
for conventional electronics but good for high frequency (eg
communications).
33. Graphene radio frequency receiver integrated circuit, S.-J.
Han et al.,Nature Communications 5, 3086
34. Graphene: ITO replacement ITO is the transparent conducting
ceramic used in all solar cells and flat panel displays. ($1.5bn
p.a.) The issue is it is very brittle. A number of rival
technologies (e.g. silver nanowires) of which graphene is one.
GrapheneSquareInc Nat. Nano, doi:10.1038/nnano.2014.226
36. Overview Graphene Structure Properties Not all graphene is
the same Production Applications Beyond graphene Patent landscape
(2013 UK IPO Report)
37. New Class of Crystalline Materials 2-DIMENSIONAL ATOMIC
CRYSTALS Initially studied : Graphene Large Variety of Material
Properties Unexplored: NbSe2 MoS2 MgB2 BiSCCO ... Lightly Touched:
Boron-Nitride Graphane Fluorographene
38. These other 2D materials are important for functional
materials TMDs give a greater change of band structure, which can
still be tuned by flake thickness. BN is insulator and not black!
Room temperature photoluminesce.
40. Layered structures by design: 2D solar cell Flexible
photovoltaic devices with photoresponsivity > 0.1 A per watt
(corresponding to an external quantum efficiency of above 30%)
Britnell et al, Science, 340, pp 1311-1314, 2013 Gold nanodots
Graphene electrode Graphene electrode MoS2 BN
41. Conclusions Graphene and other 2D materials show tremendous
potential for a range of applications. New ways to tune materials
and structures to gain unique properties. Challenge is how to
translate the exception properties seen on single flakes in to
industrial applications.
