Transcript Title: Getting an inside view with spin probes on interface

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
Nr.
Crt
Budget chapter
2007
2008
2009
2010
Total
(lei)
1.
Personnel
32000
150000
150000
108000
440000
2.
Indirect costs
14000
64000
56000
36000
170000
3
Mobilities
4000
32000
32000
17000
85000
4.
Logistics
20000
74000
42000
19000
155000
5.
Total
70000
320000
280000
180000
850000
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 spinlabeled thiol ligands bound to Au nanoparticles deposited in
silica mesopores.
Team
Name
Birth date
Job
Ph. D.
Agneta Caragheorgheopol
1941
Senior Researcher I
PhD
Gabriela Ionita
1969
Reseacher
PhD
Florenta Savonea
1972
Reseacher
PhD
Adina Rogozea
1980
Assistant Reseacher
PhD Student
Mariana Nicolescu
1976
Assistant Reseacher
PhD Student
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 web
3. 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, 2591
5. 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 ΒCyclodextrine 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; 2005present Ph D student at University “Politehnica” Bucharest.
Competence: UV – VIS spectroscopy, Chemiluminescence, EPR studies on mesoporous materials synthesis
1.
2.
M. Mihaly, A. Rogozea, A. Meghea – IX International Conference on Frontieres of Polymers and Advanced
Materials, Cracow, Poland, 2007.
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.