Toward Molecular Level Understandings of Hydrogen Evolution Reaction on Platinum Surface

Theelectrocatalytic hydrogen evolution reaction (HER) is of centralimportance for water electrolysis and green hydrogen production. Platinumrepresents the state-of-the-art electrocatalyst for the HER. The HERon the platinum surface displays distinct pH dependent kinetics, showingmuch more sluggish kinetics in alkaline media than in acidic electrolytes.The fundamental origin of the pH-dependent HER kinetics has attractedsubstantial interest in the electrocatalysis community. Considerableefforts have been made to understand the distinct HER kinetics indifferent electrolytes, although with frequent inconsistencies amongdifferent studies. A fundamental molecular level understanding ofthe pH dependent HER kinetics remains elusive but is essential fordeveloping more efficient and cost-effective water electrolysis technologies.This Perspective summarizes the current status of the mechanisticunderstanding of HER on platinum surface, analyzes several intertwinedfactors that could alter the fundamental molecular pathways and reactionkinetics in different electrolytes, and highlights the challengesand opportunities associated with advancing the mechanistic understandingof HER on platinum surface.

Automated summary

The electrocatalytic hydrogen evolution reaction (HER) is crucial for water electrolysis and green hydrogen production. Platinum is the leading electrocatalyst for HER, but its kinetics vary with pH conditions. Understanding the pH-dependent HER kinetics at a molecular level is essential for advancing water electrolysis technologies.