One-step fabrication of amorphous Ni-Fe phosphated alloys as efficient bifunctional electrocatalysts for overall water splitting

Abstract

Herein, the amorphous Ni-Fe-P alloys with different phosphorus concentrations were fabricated by the one-step electrodeposition, and the electrocatalytic activities toward hydrogen and oxygen evolution reaction (HER and OER) were evaluated in alkaline solution. It was found that the doped phosphorus played an important role in the formation of amorphous structure and improving active sites. The Ni-Fe-P electrocatalysts with the optimized phosphorus concentration exhibited the simultaneously enhanced HER and OER performances. Furthermore, Ni-Fe-P electrocatalysts as the bifunctional electrodes displayed the excellent water splitting performance and durability with a cell potential of 1.71 V (on Cu sheet) and 1.59 V (on Ni foam) reaching 10 mA·cm−2 significantly better than that of as-synthesized Ni-Fe alloys. Additionally, the boosting electrocatalytic performance was discussed in detail. The simultaneous improving HER and OER performances of Ni-Fe-P electrocatalyst might broaden the horizon in designing the highly efficient and earth-abundant electrocatalyst to produce hydrogen by electrocatalytic water splitting.