Interface Engineering of High-Energy Faceted Co3O4/ZnO Heterostructured Catalysts Derived from Layered Double Hydroxide Nanosheets

The interfaces of heterogeneous catalysts provide great contributions in improving catalytic activity due to the existing edge and corner sites with less coordinative unsaturation active sites. However, the active sites are generally limited due to suboptimal large lateral size and thickness. Heterostructured catalysts with abundant heterostructure interfaces provide a possible protocol to address the above issue. Herein, we describe the successful fabrication of heterostructure of high-energy {112} faceted Co3O4 nanosheets (similar to 20 nm) confined by highly active {001} faceted ZnO nanosheets, via calcination of ZnCo layered double hydroxide. The resulting Co3O4/ZnO heterostructure exhibits outstanding performance in an acceptorless dehydrogenative coupling reaction with >99% yield. X-ray absorption fine structure and density functional theory calculations reveal that the high activity can be attributed to the exposure of the highly active {112} facets of Co3O4 and the abundant interfaces of Co3O4/ZnO heterostructure, in which the ZnO facilitates electron transfer and lowers the reaction barrier as electronic promoter.