Energy-free corrosion engineering for in-situ growth of iron oxyhydroxide nanosheets on nickel foam toward efficient oxygen evolution

Abstract

The catalytic activity of electrode materials plays a pivotal role in determining the overall efficiency of water electrolysis. Developing low-cost and highperformance electrocatalysts for the oxygen evolution reaction (OER) is therefore crucial for advancing sustainable hydrogen production. Here, we report a facile, roomtemperature corrosion engineering strategy for the in-situ growth of FeOOH nanosheets on nickel foam (NF; labeled as NiFeNa). The obtained self-supported electrode exhibits outstanding OER activity in alkaline condition, requiring an overpotentials of only 201 mV to deliver a current density of 10 mA cm -2 -comparable to that of noble metal-based catalysts. Post-reaction characterizations reveal that the active phase consists of nickel oxyhydroxide (NiOOH) formed via in situ surface reconstruction beneath the FeOOH overlayer. DFT confirmed the significantly synergistic effect from heterostructure of NiOOH/FeOOH for improving the conductivity and facilitating OER. This work represents an energy-efficient and scalable approach for fabricating high-performance electrocatalysts, offering valuable insights into corrosion-assisted material design for broad applications in electrochemical energy conversion.