Investigation of Co3O4–CeO2 Composite Oxide as Catalyst for the Decomposition of N2O

Co3O4–CeO2 composite oxides with various ratios of Ce/Co were fabricated by the hydrothermal method, and their activities in N2O decomposition have been studied. Co3O4–CeO2 catalyst is more active than pristine Co3O4 and CeO2 catalysts. Over Co3O4–CeO2 catalyst the strong interaction between Co3O4 and CeO2 existed, which suppressed the crystallization of Co3O4, resulting in the large surface area. Particularly, the synergetic effect between Co3O4 and CeO2 induces the formation of more active Co3+ and enhanced redox property of Co3O4–CeO2 catalyst. The desorption of adsorbed oxygen, which is the key step in N2O decomposition, can be promoted due to the existed redox cycle (Co2+  + Ce4+  ↔ Co3+  + Ce3+). Therefore, Co3O4–CeO2 composite oxide showed high activity for N2O decomposition.