| 초록 |
Cobalt oxide (Co3O4) is a promising catalytic material for CO oxidation. When CeO2 is deposited on Co3O4, the reaction rate is improved due to the superior oxygen supply of CeO2. To understand the role of the CeO2-Co3O4 interface, we designed novel CeO2-deposited Co3O4 nanocubes (NCs) with controlled CeO2 layers. By selective deposition of CeO2 to Co3O4 NCs by varying surfactant concentration and pH, Co3O4 NCs covered with 1-, 3-, and 6 faces of CeO2 layers (CoCe-1F, CoCe-3F, and CoCe-6F) were prepared. Various in situ characterization studies reveal that the deposited CeO2 supplies oxygen to the Co3O4 surface, preventing Co3O4 from being easily reduced. CoCe-3F with a maximum Co3O4/CeO2 active interface exhibits the best CO oxidation rate due to the flexible change of the oxidation state at the interface. In this study, the reaction mechanism is clearly understood by investigating the changes in the oxidation state during the CO oxidation reaction at the Co3O4/CeO2 interface. |
