On the Origins of Intrinsic Limitations of Electrocatalytic Hydrogen Evolution in Alkaline Media

Abstract

Electrocatalytic hydrogen evolution reaction (HER) in alkaline media was investigated in comparative relationship to HER in acidic media. Experimentally obtained adsorption free energies for 13 d-metals were used to study the impact of intermediate coverage on HER activity trends, and how activity trends relate to trends in activation energies and preexponential frequency factors. A mechanistic picture of water discharge and adsorbed intermediate formation was analyzed in the light of recent experimental findings with the goal of creating a more comprehensive picture of HER electrocatalysis in alkaline media.