Amorphous Phosphates Tailor Local Proton Supply for Alkaline Hydrogen Evolution Electrocatalysis

Abstract Hydrogen (H 2 ) is irreplaceable as a feedstock in varied industrial scenarios, and alkaline water electrolysis allows for H 2 production without costly proton exchange membrane and noble metals with limited reserves. However, alkaline solution is devoid of directly available protons, leading to suboptimal electrochemical H 2 ‐evolving kinetics even on catalysts with high intrinsic activities like CoP. On the other hand, high local acidity (i.e., superfluous protons) can lead to undesirable catalyst corrosion and active site blocking by excessive hydrogen coverage. Herein, a “cobalt phosphate‐clothed‐CoP (CoPi@CoP)” nanoarray catalyst is developed for proof of concept to explore a possible proton…