A Scalable Strategy of “Ball‐Milling‐Assisted Laser Scanning Method” to Achieve Cr 2 Ni 3 Catalyst: An Unprecedented Robust Anode for Oxygen Evolution Reaction

Abstract Industrial water‐alkali splitting is facing high energy consumption due to the high overpotential of commercial Ni mesh anode in oxygen evolution reaction (OER) processing. Herein, a simple ball‐milling‐assisted laser scanning strategy was employed to introduce the hardest Lewis acid chromium (Cr) into the Ni matrix to form Cr2Ni3 catalysts supported by Ni mesh, endowing such NiCr/Ni mesh anode a robust OER performance at a low‐cost. It is shown that facilitating the self‐adsorption of oxygen species and promoting the leaching of soluble Cr cations aids in reconstructing Ni cations into active (oxy)hydroxide species. This study explores the innovative development of Cr‐doped NiCr/Ni mesh catalysts to create porous NiCr/Ni alloys with Cr2Ni3 as the active phase. The optimal Ni 0.5 Cr 0.5 ‐NM electrode demonstrates ultra‐low overpotentials of 293 mV and 321 mV at 50 and 100 mA cm −2 , respectively, while maintaining excellent stability for over 100 hours at 100 mA cm −2 . This work provides insight into the batch fabrication of customized OER anodes for sustainable hydrogen production.