Crystal plane regulation and heterostructure construction of ZnIn2S4/h-BN for boosting photocatalytic hydrogen evolution

Abstract

Visible light photocatalytic decomposition of water to form hydrogen provides a green and safe production method for clean energy, in which high activity and stability of heterocatalysts are high demand. In this paper, we report an inorganic anion regulation strategy to tune different exposed crystal planes of hexagonal ZnIn₂S₄, while modifying them with h-BN cocatalyst to form van der Waals heterojunction (vdWH) and reduce the photocorrosion, thereby boosting the photocatalytic hydrogen evolution activity. Consequently, ZnIn₂S₄(102)-20BN (ZIS-20BN) photocatalysts showed a remarkable photocatalytic H₂ production performance of 3.61 mmol/g_cat/h with a 10 W LED as the light source, 1.64 times higher than that of ZnIn₂S₄(102) (ZIS-(102)). Moreover, characterization and density functional theory calculations demonstrated that ZIS-(102) exhibited the lowest work function and the introduction of an appropriate amount of h-BN induced the formation of the van der Waals heterostructure, which are conducive to the improvement of the photocatalytic hydrogen evolution activity and stability. Therefore, this study provides a new feasible option for the rational design of heterojunction photocatalysts utilizing specific crystal planes and non-noble metal cocatalysts to achieve efficient photocatalytic production of hydrogen.