Ultrastable NiFeOOH/NiFe/Ni electrocatalysts prepared by in-situ electro-oxidation for oxygen evolution reaction at large current density

The bottleneck of large-scale hydrogen production from water splitting is the instability of the catalysts with excellent catalytic activity for oxygen evolution reaction (OER) at large current density (>1000 mA cm-2). In this work, a simple and efficient strategy including H2 bubbles-templating cathodic reduction and in situ electrooxidation was designed for the preparation of NiFeOOH/NiFe/Ni catalysts with laminar structure on Ni mesh (NM). As-prepared NiFeOOH/NiFe/Ni electrocatalyst for OER showed a small overpotential of 290 mV and 300 mV to achieve a current density of 500 and 1000 mA cm-2 in a three-electrode system, respectively. What's more, the water-alkali electrolyzer using NiFeOOH/NiFe/Ni as the anode and Ni/NM as the cathode can deliver 10 mA cm-2 at 1.52 V and steadily operate at 500 mA cm-2 for 100 h, suggesting the strategy given by this work is a promising pathway to achieve non-noble electrocatalysts for industrial water splitting at large current.

Automated summary

A strategy for preparing NiFeOOH/NiFe/Ni catalysts with excellent catalytic activity for OER has been designed in this study, allowing efficient hydrogen production from water splitting at large current densities. The water-alkali electrolyzer using this catalyst as the anode demonstrates stable performance for industrial water splitting.