Surficial Engineering of Cathodic Protection Strategy via P‐Doped NiCuV Monolithic Electrode for Enhanced Hydrogen Evolution Reaction in Alkaline Media

Abstract The concentrated alkaline passivates the monolithic electrode for electrochemical hydrogen evolution reaction (HER) in the alkaline water electrolysis (AWE) industry. Herein, a surface engineering of cathodic protection via one‐step co‐electrodeposition of P into NiCuV is presented and the achieved monolithic electrode exhibits an enhanced electrochemical catalytic behavior and constant durability with a feedback potential of −0.75 V versus the reversible hydrogen electrode (RHE) under an extremely high current density of 1A cm ⁻² for more than 270 h in alkaline media. The strategy of cathodic protection optimises the charge density redistribution by forming a phosphate surface layer. This preserves the particular metal (alloy) phase from oxidation while also modulating the heterarchical porous structure through P incorporation. Furthermore, an anion‐exchange membrane water electrolysis (AEMWE) with the NiCuVP serving as the HER catalyst and the NiFeCr LDH as the OER catalyst is constructed, which exhibits a current density of 912 mA cm ⁻² at 2 V at 80 °C with 30 wt.% KOH electrolytes. The resultant factors for activity and durability such as the electrochemical specific area, redox behaviors and surface hydrophilicity are also systematically discussed. This research presents a practical protocol for the anticorrosion and active enhancement of AWE and AEMWE cathodes.