One-step synthesis of well-structured NiS–Ni2P2S6 nanosheets on nickel foam for efficient overall water splitting

Abstract

One-step fabrication of efficient and self-supported electrocatalysts as bifunctional electrodes for water splitting is of prime importance but still challenging. Herein, we demonstrated a facile approach for the in situ growth of NiS–Ni₂P₂S₆ nanosheets on nickel foam (NF) (NiS–Ni₂P₂S₆/NF) via one-step calcination at low temperature. Benefitting from the fast electron and mass transfer and the unique 3D self-supported structure as well as the synergistic effect between NiS and Ni₂P₂S₆, the optimized NiS–Ni₂P₂S₆/NF exhibits superior OER and HER electrocatalytic activity in 1.0 M KOH with small overpotentials of 220 mV and 140 mV to achieve the current density of 10 mA cm⁻², respectively. Moreover, the as-prepared NiS–Ni₂P₂S₆/NF could be used as both the cathode and anode in a two-electrode water splitting cell, which can deliver the current density of 10 mA cm⁻² under a cell voltage of 1.64 V with satisfactory stability, implying its promising prospects in practical scale-up applications.