Growing ZnIn2S4 nanosheets on FeWO4 flowers with p-n heterojunction structure for efficient photocatalytic H2 production

Constructing heterojunction structure can efficiently accelerate the separation and transfer of charge carriers and improve the photoactivity. Herein, a high-performance FeWO4/ZnIn2S4 composite with abundant and tight 2D/ 2D hetero-interfaces was rational designed and prepared. ZnIn2S4 nanosheets as hydrogen evolution species uniformly grow on the surface of FeWO4 flower, constructing a unique face-to-face hierarchical architecture. A maximum H-2 production rate of 3531.2 mu mol h(-1) g(-1) was obtained at the optimal mass ratio of FeWO4 to ZnIn2S4 , which was 35 times higher than pure ZnIn2S4 . Based on the experimental results and the Density Functional Theoretical calculation results, a possible p-n heterojunction mechanism and the transfer route of photoinduced charges toward the improved H-2 production were proposed. The p-n heterojunction between FeWO4 and ZnIn2S4 nanosheets plays a key role in enhancing photocatalytic H-2 production activity. Moreover, the intimate interface between two components and the preferable hydrophilic property favors the improved H-2 evolution rate.