Recent progress in engineering molybdenum diselenide based electrocatalysts for hydrogen evolution reaction in acidic medium

Hydrogen production through electrochemical water splitting has attracted substantial interest as a low-carbon route for future clean energy systems. However, the widespread adoption of this technology is largely constrained by the dependence on noble-metal catalysts for the hydrogen evolution reaction (HER). In recent times, transition metal dichalcogenides (TMDs) emerge as prospective solutions on account of their tunable electronic structures and favourable catalytic properties. Among them, molybdenum diselenide (MoSe 2 ) witnesses a surge in scholarly attention because of its layered structure, variable phase characteristics and ability to expose catalytic active sites. Despite several reviews covering TMD based electrocatalysts, a comprehensive analysis on catalyst design for achieving both activity and stability for HER in acidic environments is still lacking. This review evaluates recent advances in MoSe 2 based electrocatalysts for acidic HER, offering insights into catalyst engineering strategies and future research directions for the rational design of efficient materials for HER.