CoFe-OH Double Hydroxide Films Electrodeposited on Ni-Foam as Electrocatalyst for the Oxygen Evolution Reaction

Abstract

Cobalt-iron double hydroxide (CoFe-OH) films were electrochemically deposited on 3D Ni foam electrodes for the oxygen evolution reaction (OER). The dependence of the OER activity on film composition and thickness was evaluated, which revealed an optimal Fe:Co ratio of about 1:2.33. The composition of the catalyst film was observed to vary with film thickness. The electrodeposition parameters were carefully controlled to yield microstructured Ni-foam decorated with CoFe-OH films of controlled thickness and composition. The most active electrode exhibited an overpotential as low as 360 mV OER at an industrial scale current density of 400 mA cm-2 that remained stable for at least 320 h. This work contributes towards the fabrication of practical electrodes with the focus on the development of stable electrodes for electrocatalytic oxygen evolution at high current densities.