Roles of hydroxyl and oxygen vacancy of CeO2•xH2O in Pd-catalyzed ethanol electro-oxidation

In the field of noble metal-catalyzed alcohol electro-oxidation reaction (AOR), huge attention is paid on the composition, size, facet, and structure of the metals, while the support engineering should also be emphasized. CeO2 has been widely used as an unique support in AOR, primarily due to its abundant oxygen vacancies (O-v). Herein, we report CeO2 center dot xH(2)O nanoparticles with both massive hydroxyl groups (OH) and O-v remarkably enhance the catalytic activity and stability of Pd toward ethanol oxidation reaction (EOR). The CO striping experiments and density functional theory (DFT) calculations suggest that OH and O-v on CeO2 center dot xH(2)O surface bring about a large downshift of Pd d-band center and a significant weakening of CO absorption on Pd. Moreover, OH and O-v also play synergic roles in the removal of toxic intermediates. Consequently, the important roles of OH and O-v of CeO2 center dot xH(2)O are confirmed in Pd-catalyzed EOR. The facile CeO2 center dot xH(2)O-enhanced strategy can contribute to the catalyst design for other energy conversion reactions.

Automated summary

In this study, CeO2·xH2O nanoparticles were used as a support material for the catalyst, and the presence of hydroxyl groups and oxygen vacancies significantly enhanced the catalytic activity and stability of Pd for ethanol oxidation reaction.