Institut des
NanoSciences de Paris
insp
Accueil > Evénements > Séminaires > Archives 2013 > Chemical reactivity (...)
insp
5.jpg

Seminaire Oxydes en basses dimensions

Chemical reactivity of TiO2  : from nanoclusters to surfaces - Monica Calatayud - Mardi 19 février 2013 à 10 h 30

Monica Calatayud, Laboratoire de Chimie Théorique de l’UPMC
Mardi 19 février 2013 à 10 h 30, INSP, salle 407, couloir 22-32, 4e étage

Laboratoire de Chimie Théorique UMR 7616, Université Pierre et Marie Curie and CNRS, Paris, France Institut Universitaire de France

In the last years there has been a considerable effort in determining structure-properties relationships for titania nanoclusters due to their technological applications in many fields. The smallest TiO2 clusters have been obtained in collision induced dissociation experiments, and a number of computational studies are devoted to the determination of their geometry. The lowest energy isomers are searched by means of different algorithms and techniques in order to explain the experimental observations. In this work we aim at exploring the chemical reactivity of such nanoclusters in terms of their structural and electronic features. The acidic and basic properties have been modeled by computing the gas-phase cluster interaction with probe molecules (H+ and NH3 respectively[1][2]). The chemical reducibility by electron transfer has been determined by the adsorption of H2.[3] The results show that the local topology dominates the reactivity of these nanostructures, whereas no trend is observed with the size. Finally, diffusion processes of H2 at selected TiO2 surfaces will be discussed.[4][5][6]

References

[1] Reactivity of (TiO2)N clusters (N=1-10) : probing gas-phase acidity and basicity properties, M. Calatayud, L. Maldonado, C. Minot J. Phys. Chem. C 112 16087 (2008)
[2] Is there a nanosize for the activity of TiO2 compounds ? M. Calatayud, C. Minot J. Phys. Chem. C 113 12186 (2009)
[3] Theoretical study of H2 interaction with (TiO2)N clusters (N=1-10), O. Syzgantseva, P. Gonzalez-Navarrete, M. Calatayud, S. Bromley, C. Minot J. Phys. Chem. C. 115 15890 (2011)
[4] Diffusion versus Desorption : Complex Behavior of H Atoms on an Oxide Surface, X.-L. Yin, M. Calatayud, H. Qiu, Y. Wang, A. Birkner, C. Minot, C. Wöll Chem. Phys. Chem. 9 (2008) 253 -256
[5] Comment on “Imaging of the Hydrogen Subsurface Site in Rutile” M. Calatayud, X.-L. Yin, H. Qiu, Y. Wang, A. Birkner, C. Minot, Ch. Wöll Phys. Rev. Lett. 104 (2010) 119603
[6] Hydrogen Adsorption and Diffusion on the Anatase TiO2(101) Surface : A First Principles Investigation, M. Islam, M. Calatayud, G. Pacchioni J. Phys. Chem. C 115 (2011) 6809–6814