Construction of Hierarchical Hollow Co 9 S 8 /ZnIn 2 S 4 Tubular Heterostructures for Highly Efficient Solar Energy Conversion and Environmental Remediation

Abstract Visible‐light‐responsive hierarchical Co 9 S 8 /ZnIn 2 S 4 tubular heterostructures are fabricated by growing 2D ZnIn 2 S 4 nanosheets on 1D hollow Co 9 S 8 nanotubes. This design combines two photoresponsive sulfide semiconductors in a stable heterojunction with a hierarchical hollow tubular structure, improving visible‐light absorption, yielding a large surface area, exposing sufficient catalytically active sites, and promoting the separation and migration of photogenerated charges. The hierarchical nanotubes exhibit excellent photocatalytic H 2 evolution and Cr VI reduction efficiency. Under visible‐light illumination, the optimized Co 9 S 8 /ZnIn 2 S 4 heterostructure provides a remarkable H 2 generation rate of 9039 μmol h −1 g −1 without the use of any co‐catalysts and Cr VI is completely reduced in 45 min. The Co 9 S 8 /ZnIn 2 S 4 heterostructure is stable after multiple photocatalytic cycles.