Co(OH)2-Ni(OH)xSy amorphous composite electrocatalysts prepared by electrodeposition method for efficient oxygen evolution reaction

In this paper, an amorphous composite electrocatalyst of Co(OH)(2)-Ni(OH)(x)S-y was prepared by a simple and rapid electrochemical deposition method on nickel foam (NF). The electrochemical performance for oxygen evolution reaction (OER) was tested in 1 M KOH solution. The overpotential of Co(OH)(2)-Ni(OH)(x)S-y (Co:Ni = 9:1) electrode was 423 mV at 50 mA cm(-2). The potential of the Co(OH)(2)-Ni(OH)(x)S-y (Co:Ni = 9:1) sample remained essentially unchanged from the initial potential of 1.651 V after 12 h of stability test. In this catalyst, the strong synergistic effect between cobalt and nickel ions, the greatly increased amorphous defect sites and oxygen vacancies, and the abundant electrochemical specific surface area together lead to the increased electrocatalytic activity and high electrocatalyst stability. This amorphous CoNi-based composite electrocatalyst prepared by simple electrodeposition has certain significance for the preparation of hydrogen energy.