Structure and catalytic reactivity of mixed Ce-Ga oxides: a periodic DFT study of the bulk material

PAOLA QUAINO; FREDERIK TIELENS; CHRISTIAN MINOT; MONICA CALATAYUD; ADRIAN BONIVARDI

Salta

Congreso; XVII Congreso Argentino de Catalisis - VI Congreso de Catalisis a a del Mercosur; 2011

Doping CeO2 with gallium leads to the synthesis of catalysts with promising properties for their application as fuel cell. The high reactivity of these materials is investigated in the present work from a theoretical point of view by menas of the construction of a structural model. The main results are the following i) the bulk material respects the pure ceria structure, with important local relaxations around the gallium site ii) the most reactive models are those where gallium sites are isolated in the bulk structure iii) reactivity os modifies as a consequence of a decrease in the band gap, meading to a higher reducibility compared to pure ceria. The results presented here are in agreement with experimental data and allow an analysis of the structure-reactivity relationship at a molecular level.