Al2O3 supported hybrid Pd-CeO2 colloidal spheres and its enhanced catalytic performances for methane combustion

Fabrication of novel nano-catalyst with improved activity and stability has been a hot topic in heterogeneous catalysis. Herein a novel approach was designed to synthesize Pd-CeO2 colloidal assembled spheres (CASs) in one-pot fashion. The Pd clusters were encompassed by the CeO2 nanocrystals with a high dispersity. Based on this hybrid structure, the Pd/ceria interface area can be greatly improved. After Pd-CeO2 CASs was supported on gamma-Al2O3, its catalytic activity for CH4 combustion was evaluated. The result shows that Al2O3 supported Pd-CeO(2)CASs exhibits an improved catalytic activity and stability, compared to the Pd/CeO2 catalyst prepared by impregnation method. The results of several characterization techniques indicate that the enhanced catalytic activity of Al2O3 supported Pd-CeO2 CASs can be attributed to the more interfacial Pd-O-Ce species and the more surface active oxygen species. (C) 2019 Chinese Society of Rare Earths. Published by Elsevier B.V. All rights reserved.