Optimized NiFe-LDH catalyst layers boost anion exchange membrane water electrolyzer performance and durability

The optimization of anion exchange membrane water electrolyzers (AEMWEs) relies on active, stable catalysts and well-designed catalyst layers. This study investigates the impact of tumbler ball milling on a nickel–iron layered double hydroxide (Ni 3 Fe-LDH) catalyst for the oxygen evolution reaction (OER). Milling reduced catalyst clusters from 1-100 μm to 30 nm, increasing the geometrical surface area by 8.8-fold. Optimized solvent compositions and dispersing times enhanced catalyst dispersion stability. Tailoring the electrode structure reduced internal electronic resistances and charge-transfer resistances of the membrane electrode assembly. The optimized electrode exhibited outstanding single-cell performance, reaching 1.83 V at 2 A cm −2 with stable durability of 1000 h and a minor degradation rate of 62 μV h −1 . This work presents a scalable approach to NiFe-LDH catalyst treatment and dispersion control, demonstrating the importance of research and optimization across scales to improve performance and support the practical advancement of hydrogen technologies.