Strong metal-support interaction, by alloying, in a Pd/Ga2O3 catalyst during selective methanol synthesis via CO2 hydrogenation

S.E. COLLINS; M.A.BALTANÁS; A.L. BONIVARDI; C. MIRA; J.J. CALVINO; S. BERNAL

Seoul, Corea

Congreso; 14th International Congress on Catalysis; 2008

The effect of the palladium-gallia interaction on Pd(1 wt.%)/gamma-Ga2O3 is studied. A detailed HRTEManalysis of the pre- and post- reaction catalysts showed a dramatic encapsulation of Pd by Ga2O3 on the latter. Afteradsorbing CO2 and switching to a H2/CO2=3 flow, IR spectroscopy showed that the hydrogenation of the (bi)carbonatesurface species to formate groups on Ga2O3 takes place only over the pre-reaction catalyst. These observations,together with the effect of the reduction temperature on the CO adsorption uptake and speciation (via FTIR), suggestthat the strong metal-support interaction under reaction conditions is related to a Pd-Ga alloy formation.