Laser-directed approach for low-loading and highly efficient transition-metal-based high-entropy alloy anode for alkaline water electrolysis

High-entropy alloys (HEAs) offer substantial potential for electrocatalysis due to lattice distortion, entropy stabilization, and the ‘cocktail effect,’ which create numerous catalytic centres. However, a significant challenge remains in developing reliable and scalable fabrication methods capable of producing nanometer-level HEA coatings to minimize the loading of critical raw materials (CRMs) without compromising performance. Addressing this gap, we report a laser-directed approach f or the synthesis of FeCoNiZnMn (FCNZM) HEA thin films onto nickel fibre (NFb) substrates. Beyond reducing the time and expense, this method offers strong HEA-substrate interactions, making it more active and durable in a harsh alkaline environment. As a result, the optimized FCNZM_2td_25p electrocatalyst demonstrates exceptional kinetics with an overpotential of 235.5 mV at 10 mA cm −2 and a favourable Tafel slope of 48 mV dec −1 . This initial activity is matched by extraordinary stability, maintaining performance for over 100 h at a high current density of 500 mA cm −2 and exceeding 160 h in a single-cell configuration against an Ir/NFb benchmark. Post-mortem characterization via TEM, XPS, and XAS reveals that the superior durability originates from a dynamic restructuring process involving the leaching of an unstable Zn-rich surface layer. These results demonstrate that our laser-directed approach provides a scalable pathway for low-loading, highly efficient transition-metal-based HEA anode, offering a viable PGM-free alternative for industrial alkaline water electrolysis.