Hierarchical Co Se-CdSe/MoSe /CdSe Sandwich-Like Heterostructured Cages for Efficient Photocatalytic CO Reduction.

Fabricating efficient photocatalysts with rapid charge carrier separation and high visible light harvesting is an advisable strategy to improve CO reduction performance. Herein, hierarchical Co Se-CdSe/MoSe /CdSe cages with sandwich-like heterostructure are prepared to act as efficient photocatalysts for CO reduction. In this study, the structure and composition of the final products can be regulated through the cation-exchange reaction in the presence of ascorbic acid. In the Co Se-CdSe/MoSe /CdSe cages, MoSe nanosheets function as a bridge to integrate Co Se-CdSe and CdSe on both sides of the MoSe nanosheet shell into a sandwich-like heterostructured catalyst system, which possesses multiple positive merits for photocatalysis, including accelerated transport and separation of photogenerated carriers, improved visible light utilization, and increased catalytic active sites. Thus, the optimized Co Se-CdSe/MoSe /CdSe cages exhibit remarkable visible-light photocatalytic performance and outstanding stability for CO reduction with a high CO average yield of 15.04 µmol g h and 90.14% selectivity, which are much higher than those of other control samples including single-component catalysts and binary hybrid catalysts. This study provides a promising way for the design and fabrication of high-efficiency photocatalysts.