Highly efficient FexNi1-xOy/CP electrode prepared via simple soaking and heating treatments for electrocatalytic water oxidation

The oxygen evolution reaction (OER) is a key step in the overall water splitting process. Numerous electrocatalysts have been developed to lower the overpotential and accelerate the kinetics of the OER. In this work, a simple soaking and heating treatment was used to form a stable and efficient FexNi1-xOy/CP electrode. The electrode combined nickel and iron oxides on a commercial carbon paper were used for electrocatalytic water oxidation. The best FexNi1-xOy/CP electrode (Ni/Fe = 15/1) displayed a current density of 10 mA/cm(2) at a low overpotential of 290 mV in 0.1 M KOH solution with a Tafel slope of 52 mV/dec. A higher current density of similar to 50 mA/cm(2) at the same overpotential and a lower Tafel slope of 43 mV/dec was obtained for this electrode in 1.0 M KOH solution. Excellent durability of the FexNi1-xOy/CP electrode in 1.0 M KOH solution was confirmed under a high current density of 136 mA/cm(2) at an overpotential of 340 mV. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B. V. and Science Press. All rights reserved.