Recent Advances in CuInS 2 -Based Photocathodes for Photoelectrochemical H 2 Evolution.

Photoelectrochemical (PEC) H 2 production from water using solar energy is an ideal and environmentally friendly process. CuInS 2 is a p-type semiconductor that offers many advantages for PEC H 2 production. Therefore, this review summarizes studies on CuInS 2 -based PEC cells designed for H 2 production. The theoretical background of PEC H 2 evolution and properties of the CuInS 2 semiconductor are initially explored. Subsequently, certain important strategies that have been executed to improve the activity and charge-separation characteristics of CuInS 2 photoelectrodes are examined; these include CuInS 2 synthesis methods, nanostructure development, heterojunction construction, and cocatalyst design. This review helps enhance the understanding of state-of-the-art CuInS 2 -based photocathodes to enable the development of superior equivalents for efficient PEC H 2 production.