Hierarchical Co_0.85 Se-CdSe/MoSe₂ /CdSe Sandwich-Like Heterostructured Cages for Efficient Photocatalytic CO₂...

Fabricating efficient photocatalysts with rapid charge carrier separation and high visible light harvesting is an advisable strategy to improve CO₂ reduction performance. Herein, hierarchical Co_0.85 Se-CdSe/MoSe₂ /CdSe cages with sandwich-like heterostructure are prepared to act as efficient photocatalysts for CO₂ 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_0.85 Se-CdSe/MoSe₂ /CdSe cages, MoSe₂ nanosheets function as a bridge to integrate Co_0.85 Se-CdSe and CdSe on both sides of the MoSe₂ 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_0.85 Se-CdSe/MoSe₂ /CdSe cages exhibit remarkable visible-light photocatalytic performance and outstanding stability for CO₂ reduction with a high CO average yield of 15.04 µmol g^-1 h^-1 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.