Superior performance of gold supported on doped CeO2 catalysts for the preferential CO oxidation (PROX)

Herein, the preferential oxidation of CO in excess hydrogen (PROX reaction) was studied over Au catalysts supported on ceria and Y or Nb doped ceria. Both supports and catalysts have been extensively characterized by a number of advanced techniques; XRD, N2-adsortion, Raman spectroscopy, XPS, and H2-TPR. The catalytic results showed that when an ideal mixture of H2 and CO is used for the PROX reaction the gold supported on pure ceria behaves better than the others samples. However, when a typical reformate gas composition containing CO2 and H2O is used, the gold supported on Nb doped sample behaves better than gold supported in pure ceria. It is suggested that niobium hampers the strong adsorption of CO2 and H2O in the active sites, thus improving the catalytic performance in real reformate gas.

Financial support from Generalitat Valenciana and Ministerio de Economía y Competitividad (Spain) through projects PROMETEO/2009/02-FEDER and MAT2010-21147 is gratefully acknowledged. EOJ also thanks the CNPq – Brazil for her grant. EVRF gratefully acknowledge the Ministerio de Economía y Competitividad (Spain) for his Ramon y Cajal grant (RYC-2012-11427).