In2S3-modified ZnIn2S4 enhanced photogenerated carrier separation efficiency and photocatalytic hydrogen evolution under visible light

Abstract

ZnInS (ZIS) has limited photocatalytic hydrogen production due to low visible light utilisation and insufficient separation efficiency of photogenerated carriers. This study utilized a simple hydrothermal method to prepare InS/ZnInS (INS/ZIS) heterojunctions. The addition of InS (INS) improves the separation and movement of photogenerated charges, and makes better use of visible light. The material was analysed using SEM, TEM, XRD, XPS and photoelectrochemical tests. Results from the transient photocurrent (TPR) and photoluminescence (PL) experiments show a photocurrent density of approximately 1.8 μA/cm, which is 3 times greater than the ZIS (0.6 μA/cm) density, when the INS mass is 5 %. And at this time, INS/ZIS boasts the most effective photogenerated carrier separation. The hydrogen photocatalytic generation test results showed that the photocatalytic hydrogen production rate of 5-INS/ZIS (5690 μmol/g/h) was 8.4 and 66.9 times higher than that of pure ZIS (710 μmol/g/h) and INS (89 μmol/g/h), respectively. The enhanced activity is due to the creation of type II heterojunctions, which improve the separation and transfer of light-generated charges. The research presents an innovative approach to creating composites based on ZIS.