One-step synthesis of amorphous Ni-Fe-P alloy as bifunctional electrocatalyst for overall water splitting in alkaline medium

Design of inexpensive and highly efficient bifunctional electrocatalyst is paramount for overall water splitting. In this study, amorphous Ni-Fe-P alloy was successfully synthesized by one-step direct-current electrodeposition method. The performance of Ni-Fe-P alloy as a bifunctional electrocatalyst toward both hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) was evaluated in 30 wt% KOH solution. It was found that Ni-Fe-P alloy exhibits excellent HER and OER performances, which delivers a current density of 10 mA cm−2 at overpotential of ∼335 mV for HER and ∼309 mV for OER with Tafel slopes of 63.7 and 79.4 mV dec−1, respectively. Moreover, the electrolyzer only needs a cell voltage of ∼1.62 V to achieve 10 mA cm−2 for overall water splitting. The excellent electrocatalytic performance of Ni-Fe-P alloy is attributed to its electrochemically active constituents, amorphous structure, and the conductive Cu Foil.