Deciphering the Exceptional Performance of NiFe Hydroxide for the Oxygen Evolution Reaction in an Anion Exchange Membrane Electrolyzer

Hydrogen production via water electrolysis with renewable electricity as input will be crucial for the coming defossilized energy age. Herein, we report an anion exchange membrane electrolyzer using Fe-doped Ni hydroxide anode catalyst that is on par proton electrolyzers in terms of performance, 2 A cm–2 at 2.046 V and 50 °C. We found Fe doping stabilizes ?-Ni(OH)2 phase, which key to ensure fast Ni(OH)2/NiOOH redox transition subsequent reaction between Ni3+/4+ electrolyte (OH–), resulting excellent oxygen evolution activity hydroxide. Spin-polarized DFT + U computations reveal local arrangement Fe3+ plays a role enabling high OER (001) facet this catalyst.