Synergistic effects of CeO_(2)/Cu_(2)O on CO catalytic oxidation:Electronic interaction and oxygen defect

For CO catalytic oxidation,Cu and Ce species are of great importance,between which the synergistic effect is worth investigating.In this work,CeO_(2)/Cu_(2)O with Cu_(2)O {111} and {100} planes were comparatively explored on CO catalytic oxidation to reveal the effects of interfacial electronic interactions and oxygen defects.The activity result demonstrates that CeO_(2)/o-Cu_(2)O {111} has superior performance compared with CeO_(2)/c-Cu_(2)O {100}.Credit to the coordination unsaturated copper atoms(Cu_(CUS)) on oCu_(2)O {111} surface,the interfacial electronic interactions on CeO_(2)/o-Cu_(2)O {111} are more obvious than those on CeO_(2)/c-Cu_(2)O {100},leading to richer oxygen defect generation,better redox and activation abilities of CO and O_(2) reactants.Furthermore,the reaction mechanism of CeO_(2)/o-Cu_(2)O {111} on CO oxidation is revealed,i.e.,CO and O_(2) are adsorbed on the Cucus on Cu_(2)O {111} and oxygen defect of CeO_(2),respectively,and then synergistically promote the CO oxidation to CO_(2).The work sheds light on the designing optimized ceria and copper-based catalysts and the mechanism of CO oxidation.