Efficient photocatalytic H2 evolution using NiS/ZnIn2S4 heterostructures with enhanced charge separation and interfacial charge transfer

The effect of multidimensional heterostructures on charge transfer and charge separation is intriguing in photocatalytic applications. Herein, NiS/ZnIn2S4 heterostructures with tailorable composition, tunable light absorption, and controllable band gap were successfully prepared by a two-step method to show uniform NiS nanoparticles with an average size of 10 nm loaded homogeneously on porous ZnIn2S4 nanosheets. Consequently, NiS/ZnIn2S4 heterostructures have markedly enhanced light absorption and efficient photocatalytic efficiency, reaching the hydrogen evolution rate of 5.0 μmol h−1 under the light irradiation at 420 nm, to be approximately three times higher than that of pure ZnIn2S4. The enhanced photocatalytic efficiency results from faster charge transfer and more efficient photogenerated electron-hole separation under beneficial band alignment. The results shed light on how the photocatalytic reaction occurs at the interface between NiS and ZnIn2S4, and can open a new avenue for synthesizing efficient photocatalysts.