Development of Au/CeO2 catalysts for preferential oxidation of CO in PEMFC

Abstract

The preferential oxidation (PROX) of CO in an H-2-rich stream was investigated over Au/MOx (M = Ti, Al, Fe, Ce) catalysts. It was found that 2.5 wt% Au/CeO2 showed the best activity for the reaction. Ceria itself had catalytic activity for the reaction and the activity increased with its decreasing crystallite size. In addition, the effect of Au particle size was investigated by means of XRD, TEM, TPR, and FT-IR spectroscopy of chemisorbed CO. This analysis showed that the number of active sites increased with decreasing Au particle size. This effect caused changes in the intensity of the FT-IR spectra of the adsorbed CO and in the reduction temperature of the catalysts.