Rationally designed hierarchical hollow CuS/CdInS heterostructure nanoboxes for boosted photoreduction of CO.

A novel double-shelled CuS/CdInS photocatalyst was rationally designed using CdInS sheets grown upon the exterior of hollow CuS nanocubes. The unique hierarchical hollow structure of CuS/CdInS provides numerous active sites and reduces carrier diffusion length. Surface sulfur vacancies mitigate the detachment of the intermediate, which is favorable for a multi-electron reaction path such as that in the production of CH. Meanwhile, a suitable band-structure alignment between p-type CuS and n-type CdInS leads to the formation of a type-II heterostructure, thus resulting in effective light-harvesting and spatial separation of electron-hole pairs for CO photoreduction. The CuS/CdInS heterostructure exhibits significantly enhanced performance with a boosted CO yield of 40.73 μmol g h as well as a noticeably improved CH selectivity (36.5%, 23.41 μmol g h). This work introduces innovative concepts in designing photocatalytic systems with unique morphologies and rational band structures, promising advancements in CO photoreduction at reduced costs.