Hierarchical ZnIn2S4: A promising cocatalyst to boost visible-light-driven photocatalytic hydrogen evolution of In(OH)3

Efficient separation of electrons and holes, associated with the reduction and oxidation, is of great importance in a photocatalytic reaction. 3D hierarchical core-shell-like ZnIn2-S-4@In(OH)(3) microspheres have been fabricated by a facile hydrothermal method via controlling the sulfur source. The marigold-like spherical ZnIn2S4 induced the in situ growth of cubic In(OH)(3) nanosheets as the outer shell, which efficiently transferred the photo-generated electrons and achieved efficient charge separation efficiency for highly photo catalytic H-2 production. Moreover, the intimate interfacial contact between ZnIn2S4 core and In(OH)(3) shell offered rectified charge transfer directions, which further boosted the charge separation. In consequence, the photocatalytic H-2 evolution under visible light irradiation was achieved on wide-gap In(OH)(3) owing to ZnIn2S4 as a cocatalyst, and a prominent photocatalytic H-2 production of 2088 mu mol g(-1) was obtained on core-shell-like ZnIn2S4@In(OH)(3) structure with an apparent quantum efficiency of 1.45% (400 nm), which was nearly 2-folds higher of H-2 production rate than the pristine ZnIn2S4. This work provides a prototype material for high efficiency of hydrogen evolution, and gives a new insight for the development of efficient heterojunction photocatalysts. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.