Construction of two-dimensional zinc indium sulfide/bismuth titanate nanoplate with S-scheme heterojunction for enhanced photocatalytic hydrogen evolution

Abstract

Improving the separation efficiency of photogenerated carriers plays an important role in photocatalysis. In this study, two-dimensional (2D)/2D zinc indium sulfide (ZnIn₂S₄)/bismuth titanate (Bi₄Ti₃O₁₂) nanoplate heterojunctions were synthesized to alter the Bi₄Ti₃O₁₂ morphology, modulate the bandgap of Bi₄Ti₃O₁₂, and enhance the utilization of light. Meanwhile, the construction of the S-scheme heterojunction establishes an internal electric field at the ZnIn₂S₄/Bi₄Ti₃O₁₂ heterojunctions interface and achieves the spatial separation of photogenerated charges. The hydrogen production rate of ZnIn₂S₄/Bi₄Ti₃O₁₂ nanoplate with the optimal ratio reaches 27.50 mmol h^-1 g^-1, which is 1.5 times higher than that of ZnIn₂S₄/Bi₄Ti₃O₁₂ nanoflower (18.28 mmol h^-1 g^-1) and 2.4 times higher than that of ZnIn₂S₄ (11.69 mmol h^-1 g^-1). The apparent quantum efficiency of ZnIn₂S₄/Bi₄Ti₃O₁₂ nanoplate reached 57.9 % under a single wavelength of light at 370 nm. This work provides insights into the study of new materials for photocatalytic hydrogen production.

Keywords: Electron transfer; Heterojunction; Hydrogen production; Morphology control; S-scheme.