Dynamic Hydrogen Bubble Templated NiCu Phosphide Electrodes for pH-Insensitive Hydrogen Evolution Reactions

A highly efficient porous NiCu-phosphide (NiCu-P) electrode is reported for a hydrogen evolution reaction (HER) in acidic, neutral, and basic electrolytes. The NiCu-P electrode was prepared via hydrogen bubbles dynamic templated electrodeposition of NiCu alloy onto nickel mesh, followed by phosphidation. Due to the synergistic interaction in NiCu-P, the material exhibits excellent HER activity in a wide pH range from 0.3–14. Current density of −10 mA cm–2 was achieved at low overpotentials of −226, −250, and −175 mV in 0.5 M H2SO4, 1 M phosphate buffer solution, and 1 M KOH, respectively. The fabricated NiCu-P electrode also shows an outstanding electrochemical stability, regardless of electrolyte pH. The NiCu-P has a slope value of −53 mV dec–1, indicating that HER at NiCu-P follows the Heyrovsky mechanism in 1 M KOH.