We present a critical analysis of the mechanism reversible hydrogen evolution reaction based on thermodynamics processes considering atomic and ionic species as intermediates. Clear distinction between molecular evolution/oxidation (H2ER H2OR) (HER HOR) reactions is made. It suggested that main describing H2ER H2OR in acidic basic solutions is: H3O++2e??(H2+)adH2+OH? its standard potential E0 =...

Abstract Sustainable, renewable and scalable production of highly pure hydrogen gas through evolution reaction (HER) in electrochemical water splitting requires efficient stable electrocatalysts. Single atom catalysts (SACs) with significant merits such as the maximum atom-utilization efficiency, unique electronic structure fascinating properties, are considered promising candidates electrocata...