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 H ₂ SO ₄ , 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.