Shanfu Sun, Siyuan Wang, Ningning Cao, Mingyao Wang, Zhenchao Sun, Xidong Hao, Yinglin Wang, Jia Zhang, Pengfei Cheng
The reasonable design of oxygen evolution reaction (OER) catalysts that simultaneously combine low energy consumption, high activity, and long-term durability under industrial-level conditions is crucial for the practical deployment of water electrolysis for hydrogen production. In the present work, a novel spontaneous electrochemical corrosion (SEC) strategy is employed to in-situ prepare the well-aligned NiFe-based (oxy)hydroxides nanosheet array film on Ni foam (NiFe-OH/NF). The resulting electrode can be fabricated at a cost of only $0.0058 per cm2 and is readily scalable. Operating as an OER catalyst in alkaline solution, NiFe-OH/NF requires an overpotential of merely 213 ± 2 mV to deliver 10 mA cm-2. More importantly, the SEC-derived NiFe-OH/NF exhibits a dynamic Fe-replenishment process during OER, in which dissolved Fe species are partially reincorporated into the catalyst surface, thereby mitigating deactivation and enabling superior durability. As a result, NiFe-OH/NF operates stably for more than 126 days (> 3024 h) at an industrial-level current density of 500 mA cm-2 in 1 M KOH containing 0.1 mM Fe3+. This work demonstrates a low-cost and scalable route to NiFe-based OER electrodes that simultaneously deliver competitive activity and remarkable durability, offering strong promise for practical alkaline water electrolysis.