Engineered Charge Transfer and Reactive Site over Hierarchical Ti3C2Tx MXene@In2S3-NiS toward Enhanced Photocatalytic H2 Evolution

Abstract Steering photogenerated electron flow to the effective reactive sites is ideal for photocatalytic H2 evolution. Herein, as a proof-of-concept, NiS is coupled with a typical Schottky heterojunction of Ti3C2Tx MXene@In2S3 through the photodepotition method towards improving the photocatalytic H2 evolution performance. In addition to the Schottky effect-mediated electron transfer in Ti3C2Tx MXene@In2S3 heterojunctions, p-n junctions form between In2S3 and NiS to extract photoinduced electrons, which is found to cooperate with the role of effective H2 evolution reactive sites. The synergistic dual functions of NiS cooporate with Ti3C2Tx MXene promote multichannel electron transfer in Ti3C2Tx MXene@In2S3-NiS hybrids to improve the photocatalytic hydrogen evolution reaction (HER) efficiency by 41 times compared to the bare In2S3. These results enlighten the engineering of the spatial transfer of photoinduced electrons to the reactive sites toward boosting the efficiency of photocatalytic HER.