Boosting the Performance of Alkaline Anion Exchange Membrane Water Electrolyzer with Vanadium‐Doped NiFe2O4

Abstract Developing efficient, economical, and stable catalysts for the oxygen evolution reaction is pivotal for producing large‐scale green hydrogen in the future. Herein, a vanadium‐doped nickel‐iron oxide supported on nickel foam (V‐NiFe 2 O 4 /NF) is introduced, and synthesized via a facile hydrothermal method as a highly efficient electrocatalyst for water electrolysis. X‐ray photoelectron and absorption spectroscopies reveal a synergistic interaction between the vanadium dopant and nickel/iron in the host material, which tunes the electronic structure of NiFe 2 O 4 to increase the number of electrochemically active sites. The V‐NiFe 2 O 4 /NF electrode exhibited superior electrochemical performance, with a low overpotential of 186 mV at a current density of 10 mA cm −2 , a Tafel slope value of 54.45 mV dec −1 , and minimal charge transfer resistance. Employing the V‐NiFe 2 O 4 /NF electrode as an anode in an alkaline anion exchange membrane water electrolyzer single‐cell, a cell voltage of 1.711 V is required to achieve a high current density of 1.0 A cm −2 . Remarkably, the cell delivered an energy conversion efficiency of 73.30% with enduring stability, making it a promising candidate for industrial applications.