Cu–Co–P electrodeposited on carbon paper as an efficient electrocatalyst for hydrogen evolution reaction in anion exchange membrane water electrolyzers.

To solve the issues of energy shortage and environmental pollution, it is essential to develop highly effective catalysts for hydrogen evolution reaction (HER) in water electrolysis. Herein, we report a facile and rapid fabrication of a Cu–Co–P catalyst on a carbon paper (CP) substrate using electrodeposition. First, the deposition conditions for Co–P/CP were optimized. The prepared Co–P consisted of numerous spheres and exhibited acceptable catalytic activity towards HER in an alkaline medium with an overpotential of 72 mV at current density of −10 mA/cm2. Further performance enhancement was achieved by the incorporation of Cu to modify the electronic structure of the Co–P catalyst. In a half-cell test, the optimized Cu–Co–P/CP exhibits remarkable performance, achieving −10 mA/cm2 at an overpotential of 59 mV, and the Tafel slope is 38 mV/dec. In a single-cell test, an anion exchange membrane water electrolyzer with a Cu–Co–P/CP cathode and commercial IrO 2 /CP anode exhibited high current density of 0.70 A/cm2 at 1.9 V cell. [Display omitted] • Cu–Co–P was electrodeposited on carbon paper while varying the Cu content. • The catalyst shows low overpotential of 59 mV to deliver −10 mA/cm2 and small Tafel slope in 1.0 M KOH. • The Cu–Co–P/CP gas diffusion electrode exhibited high cell performance (0.7 A/cm2 at 1.9 V cell) in AEMWE single cell. [ABSTRACT FROM AUTHOR]