Copper Sulfide based Photocatalysts, Electrocatalysts and Photoelectrocatalysts: Innovations in Structural Modulation and Application

Abstract Copper sulfides (Cu x S, 1 ≤ x ≤ 2) are notable for their unique photoelectric properties and potential applications, particularly in photo/electrocatalysis. These materials are valued for their tunable band gap, near‐infrared optical characteristics, and plasmonic resonance effects. However, challenges such as low catalytic activity and limited stability impede their practical applications. This review addresses these issues by exploring advanced strategies for electronic structure modulation, including atomic doping, shape alteration, heterojunction construction, and defect introduction to enhance catalytic efficiency. A detailed analysis of the optical and electrical properties of Cu x S across various stoichiometric ratios and crystal structures is provided, offering a comprehensive overview of their applications in photocatalysis, electrocatalysis, and photo/electrocatalysis. Additionally, the review synthesizes current knowledge and highlights the potential of these strategies to optimize Cu x S‐based photo/electrocatalysts, proposing future research directions to bridge the gap between theoretical studies and practical applications. This work underscores the importance of Cu x S in photo/electrocatalysis and aims to inspire further innovation and exploration in this field, emphasizing its significance in material science and engineering.