Exploratory research project,funded by CNCSIS,

PN II “Ideas” program

Title: Getting an inside view with spin probes on interface processes in the synthesis of mesoporous alumina and on

topology, dynamics and accessibility of functional groups in mesoporous materials

Director: Dr. Agneta Caragheorgheopol

01.10.2007-30.09.2010

Exploratory research project,funded by CNCSIS,

PN II “Ideas” program

Title: Getting an inside view with spin probes on interface processes in the synthesis of mesoporous alumina and on

topology, dynamics and accessibility of functional groups in mesoporous materials

Director: Dr. Agneta Caragheorgheopol

01.10.2007-30.09.2010

Budget

85000018000028000032000070000Total5.

15500019000420007400020000Logistics 4.

850001700032000320004000Mobilities3

17000036000560006400014000Indirect costs 2.

44000010800015000015000032000 Personnel 1.

Total(lei)

2010200920082007Budget chapterNr.Crt

Summary

Mesoporous materials belong to advanced, smart materials with an ordered and controlled structure, which can be used as building blocks of more complex supramolecular materials. To this end the detailed knowledge of synthesis details and of functioning parameters appears important. This project proposes the use of EPR spectroscopy of spin probes to get an inside view of the synthesis and functioning of certain mesoporous materials. The spatial and temporal resolution of information are both in the nanoscopic region, characteristic of EPR spectroscopy.We propose: To study the mechanism of mesoporous alumina synthesis by CW and pulsed EPR (ESEEM), a method which allows for the spatial distribution of alumina precursor, surfactant and solvent during synthesis to be revealed. ESEEM is unique in providing such information. To study by spin labeling the distribution, dynamics and accessibility of functional groups in mesoporous silica. This information is relevant for the catalytic activity of the corresponding materials or their use as adsorbents or as templates for the synthesis of special dimensionality products. Gold nanoparticles can be prepared and stabilized in silica mesopores. We propose to label them by adsorbing spin labels thiol ligands and to follow by EPR the dynamics and exchange reactions of those ligands in the pores, as compared to existing data for au nanoparticles in solution.

Objectives

1. The synthesis of mesoporous alumina in organic solvents with non-ionic surfactants exploring the organic/inorganic interaction during alumina precipitation;

2. To study the distribution, dynamics and accessibility of functional aminopropyl groups in the pores of silicas with different pore sizes and geometry;

3. The distribution, dynamics and exchange reactions of spin-labeled thiol ligands bound to Au nanoparticles deposited in silica mesopores.

Team

PhD StudentAssistant Reseacher1976Mariana Nicolescu

PhD StudentAssistant Reseacher1980Adina Rogozea

PhDReseacher1972Florenta Savonea

PhDReseacher1969Gabriela Ionita

PhDSenior Researcher I1941Agneta Caragheorgheopol

Ph. D.JobBirth dateName

CV Agneta Caragheorgheopol, Project Director

The main research fields related to the structural study of advanced materials are:1. Study of self-assembled systems by EPR of spin probes.

Investigated binary and ternary colloid systems : micelles, reverse micelles lyotropic hexagonal and lamellar liquid crystals, microemulsions, gels.

These studies resulted in 12 papers in ISI journals and in 2 book chapters.2. Study of hybrid organic/inorganic systems in the synthesis of mesoporous silica and alumina; 5 papers in ISI journals.3. Monolayer protected gold naoparticles, studied by spin labeled ligands. 6 papers in ISI journals.

Selected papers:1. Agneta Caragheorgheopol*, Florenta Savonea, Duncan J. Macquarrie, Rafael Luque, Dan Donescu, Mihai C. Corobea“EPR spin probe investigation

into the synthesis of mesoporous silica from the water / acetonitrile / n-dodecylamine system” J.Phys. Chem C, 2007, 111, 14500 - 14507 2. Petre Ionita, Joanna Wolowska, Victor Chechik,,* Agneta Caragheorgheopol *, “Ligand Dynamics in Spin-Labeled Au Nanoparticles”, J.Phys. Chem, 2007 on the web3. D.J.Macquarrie, B.C.Gilbert, L.J. Gilbey, A. Caragheorgheopol, F. Savonea, D.B.Jackson,B.Onida, E.Garrone and R.L.Alvarez, “Structured

mesoporous organosilicas from acetonitrile-water template system” J. Mater. Chem., 2005.4. Petre Ionita, Agneta Caragheorgheopol, Bruce C. Gilbert and Victor Chechik “ Dipol-dipol interactions in spin-labeled Au nanoparticles as a measure of

interspin distance”, J.Phys.Chem.B, 2005, 109, 3734.5. A.Caragheorgheopol, H.Caldararu, G.Ionita , F. Savonea, N. Zilkova, A.Zukal J.Cejka, “Solvent - induced textural changes of as-synthesized

mesoporous alumina, as reported by spin probe electron spin resonance” Langmuir, 2005, 21(6), 2591-7.6 A.Caragheorgheopol, H.Caldararu, M.Vasilescu, Ali Khan, D.Angelescu, N.Zilkova, J.Cejka, “ Structural Characterization of Micellar Aggregates in

Sodium Dodecyl Sulfate/Aluminum Nitrate/Urea/Water System in the Synthesis of Mesoporous Alumina”, J.Phys.Chem., 2004, 108, 7735-7743. 7. H.Wellsted, E.Sitsen, A. Caragheorgheopol and V. Chechik “Polydisperse composition of mixed monolayer-protected Au nanoparticles, Anal.Chem.

2004, 76, 2010.

Book Chapters:A.Caragheorgheopol si H.Caldararu, “EPR Spin-labelling and Spin Probe Studies of Self-assembled Systems”, in Specialist Periodical Reports: Electron

Paramagnetic Resonace, volume 17, Royal Society of Chemistry, Cambridge, 2000, p.205

V. Chechik and A. Caragheorgheopol “Getting an inside view of nanomaterials with spin labels and spin probes “in Specialist Periodical Reports Electron Paramagnetic Resonace, volume 23, Royal Society of Chemistry, Cambridge 2006

CV Elena Gabriela Ionita

1993-2002, University of Pitesti; since 2002 researcher at Institute of Physical Chemistry Bucharest. Expertise: EPR, IR, UV-Vis spectroscopy, cyclic voltammetry, TLC, organic synthesis, cyclodextrins, spin labelling. International fellowships: - NATO/Royal Society (2004-5): “Spin-Labelled Cyclodextrins: Novel Supramolecular Receptor/Reporter Units” at York University, UK;-September – December 2005, Royal Society -Short visit fellowship (York University, UK);-February-August 2006, study visit at York University CEEX 2/2005; -COST P15 – STSM, January-March 2007 (York University, UK), COST P15 – STSM June 2007, (Institute Weizmann, Rehovot).

1. Gabriela Ionita, Viorica Meltzer, Elena Pincu, Victor Chechik, “Inclusion complexes of cyclodextrins with biradicals linked

by a polyether chain - an EPR study“, Org. Biomol. Chem, 2007, 5, 1910.

2. Victor Chechik, Gabriela Ionita, “Supramolecular Complexes Of Spin-Labelled Cyclodextrins”, Organic & Biomolecular Chemistry, 2006, 3(17), 3505.

3. Gabriela Ionita, Victor Chechik, “Spin -Labelled Cyclodextrins As Hosts For Large Supramolecular Assemblies”, Organic & Biomolecular Chemistry, 2005, 3(17), 3096.4. Agneta Caragheorgheopol, Horia Caldararu, Gabriela Ionita, and Florenta Savonea, “Solvent-Induced Textural Changes

of As-Synthesized Mesoporous Alumina, As Reported by Spin Probe Electron Spin Resonance Spectroscopy”, Langmuir 2005, 21, 25915. Gabriela Ionita, V. Sahini, “Oxidation of Natural and Thermal Denatured Bovine Serum Albumin with Hydrazyl Free

Radicals in the Presence of Cyclodextrins”, J. Incl. Phenom. Macrocycl. Chem., 2004, 50, 183.

CV Florenta Daniela Savonea

Bucharest University degree-Faculty of Chemistry (1996), master (1997), Ph. D. diploma (2007). International fellowships: November 2003 – study visit at Instituto de Tecnologia Quimica, Valencia, Spain, NATO Project SfP 974217 “Synthesis of ordered mesoporous aluminas and their application as a catalyst support”; June-July 2004– study visit at Institute of Catalysis and Surface Chemistry, Cracow, Poland; August – September 2004, study visit at York University, UK, Royal Society Joint Project Grant „Structural Characterization of Self-Assembling Systems with EPR Spin Probes”.Competence: EPR and UV-VIS spectroscopy, catalysts and mesoporous materials synthesis; catalysts synthesis by sol - gel method and their testing in hydrogenolysis reactions, EPR studies on mesoporous materials synthesis.

1. A.Caragheorgheopol, H.Caldararu, G.Ionita , F. Savonea, N. Zilkova, A.Zukal, J.Cejka,”Solvent-induced textural changes of as-synthesized mesoporous alumina, as reported by spin probe electron spin resonance” Langmuir, 2005, 21(6), 2591. 2. D.J.Macquarrie, B. C.Gilbert, L.J.Gilbey, A.Caragheorgheopol, F.Savonea, D.B.Jackson, B.Onida, E.Garrone and R.Luque,”Structural mesoporous organosilicas from an acetonitrile-water template system” J.Mater.Chem.,2005,15, 3946.3. G. Ionita, R. Socoteanu and F. Savonea “ATR/FTIR Study of Mesoporous Silicate Synthesis Using Mixture of Β-Cyclodextrine and Urea as Template” Revue Roumaine de Chimie, 2005, 50(1), 71.4. F.Savonea D.Macqarrie and B.Gilbert,” A spin Probe Study of Mesoporous Silica Formation via a Neutral Templating Route”, J.Phys.Chem.B, 2003,107,6032. 5. F. Tiu, V. Pârvulescu, P. Grange and V. I. Pârvulescu, “Effect of hydrogen spillover in hydrogenolysis and cracking of butane on Co-niobia-silica catalysts”, Stud. Surf. Sci. Catal., 2001,138 , 251-258.

CV Adina Rogozea

1999 – 2003 – Bucharest University, Faculty of Chemistry; 2003 – 2005 – Master in Applied Enzymology; 2005- present Ph D student at University “Politehnica” Bucharest.

Competence: UV – VIS spectroscopy, Chemiluminescence, EPR studies on mesoporous materials synthesis 1. M. Mihaly, A. Rogozea, A. Meghea – IX International Conference on Frontieres of Polymers and Advanced

Materials, Cracow, Poland, 2007.2. M. Giurginca, G, Coara, N. Iftimie, A. Rogozea, Scientific Bulletin – University Politehnica Bucharest, 2005, 67(3),

11 - 15.

CV Mariana Nicolescu

-2000 – 2004 Bucharest University, Faculty of Chemistry, Department of Physical Chemistry;-2004 – 2006 Master Degree in Quality Control obtained at the same University

Competences: UV – VIS and IR spectroscopy, HPLC, elipsometry.