Enhanced Photoelectrochemical Water Splitting of In₂S₃ Photoanodes by Surface Modulation with 2D MoS₂ Nanosheets

Photoanodes with ample visible-light absorption and efficient photogenerated charge carrier dynamics expedite the actualization of high-efficiency photoelectrochemical water splitting (PEC-WS). Herein, we fabricated the heterojunction nanostructures of In₂S₃/MoS₂ on indium-doped tin oxide glass substrates by indium sputtering and sulfurization, followed by the metal-organic chemical vapor deposition of 2D MoS₂ nanosheets (NSs). The photocurrent density of In₂S₃/MoS₂ was substantially enhanced and higher than those of pristine In₂S₃ and MoS₂ NSs. This improvement is due to the MoS₂ NSs extending the visible-light absorption range and the type-II heterojunction enhancing the separation and transfer of photogenerated electron-hole pairs. This work offers a promising avenue toward the development of an efficient photoanode for solar-driven PEC-WS.