Scalable water electrolysis requires cost-effective, durable electrodes that operate efficiently at high current density, placing stringent demands on oxygen evolution reaction electrocatalysts. Herein, we demonstrate a three-dimensional hierarchical catalyst fabricated by growing NiFe layered double hydroxide (LDH) nanosheets directly on commercial iron foam (NiFe-LDH/FF) at room temperature. The self-supported electrode delivers low overpotentials of 228, 240, and 277 mV to reach current densities of 50, 100, and 500 mA cm–2 in 1.0 M KOH, while maintaining excellent stability. Under industrial-grade conditions (30 wt % KOH), it delivers a high current density of 1000 mA cm–2 at an overpotential of only 246 mV, outperforming many reported nonprecious metal electrocatalysts under similar conditions. This work not only presents a scalable synthesis route for high-performance NiFe-LDH anodes but also highlights the necessity of evaluating electrocatalyst durability in concentrated alkaline electrolytes for practical implementation.
Li et al. (Tue,) studied this question.