Recent Advancement in Electrocatalytic Water Splitting Facilitated by the Sulfide Oxidation Reaction

Water electrolysis represents a promising pathway for hydrogen generation. However, its practical implementation is constrained by the kinetically sluggish anodic process of the oxygen evolution reaction (OER). Recently, a strategy of replacing OER with the sulfide oxidation reaction (SOR) has garnered significant attention. By coupling SOR with the cathodic hydrogen evolution reaction (HER), this approach reduces the overall reaction overpotential, facilitates the simultaneous purification of sulfide-containing wastewater, and recovers sulfur resources, thereby achieving dual benefits of environmental remediation and economic value. This Review initiates with a systematic elucidation of the SOR mechanistic framework and comprehensively catalogs recent advancements in bifunctional electrocatalysts for integrated SOR||HER systems, such as metal (hydr)oxides, metal sulfides, heterojunction catalysts, and alloy catalysts. In light of the relationship between active site modulation and catalyst structure, we suggest methods for improving the performance of SOR catalysts and outline future directions for SOR.