Enhanced Built-in Electric Field via Work Function Engineering for Efficient Anion Membrane Water Electrolysis

Anion exchange membrane water electrolysis (AEMWE) offers promise for sustainable hydrogen production through nonacidic operation and renewable energy compatibility, yet AEMWE suffers from sluggish alkaline hydrogen evolution reaction (HER) kinetics due to inefficient Volmer steps. Herein, a work function engineering strategy was introduced to enhance interfacial charge redistribution, strengthening the built-in electric field for optimized intermediate adsorption. Chromium doping in nickel hydroxide carriers increased the work function difference between Pt nanoparticles and Cr–Ni(OH) 2 supports by 53%, and the one-step corrosion synthesis-prepared Pt/Cr–Ni(OH) 2 catalyst demonstrates exceptional HER performance. The catalyst achieved ultralow overpotentials of 18 and 156 mV at 10 mA cm –2 and 1000 mA cm –2, respectively. Integrated with NiFe-LDH in AEMWE, the system demonstrated 1.75 V at 1 A cm –2 (60 °C) with 100 h of stability. This work establishes a paradigm combining interface engineering with scalable fabrication techniques, providing critical insights for advancing AEMWE technology toward practical large-scale implementation.