Cu-mediated proximal electronic engineering in Ni/MoO2 heterostructures for industrial alkaline hydrogen evolution

The development of highly active and robust non-noble-metal catalysts for alkaline hydrogen evolution reaction (HER) is imperative for industrial anion exchange membrane water electrolysis (AEMWE). Herein, we construct a hierarchically multiphase heterostructure via a customized reduction strategy, featuring uniformly dispersed Cu and Ni metallic phases anchored onto a conductive isolated MoO 2 substrate (Cu/Ni@MoO 2 ). The catalyst achieves an ultralow overpotential of 140.7 mV at 1 A cm −2 in 1 M KOH, coupled with ampere-level operational stability exceeding 2000 h without degradation. In-situ Raman spectroscopy and theoretical analyses unveil that Cu-mediated interfacial engineering dynamically restructures interfacial water networks, reduces the water dissociation barrier and optimizes hydrogen adsorption energy. Impressively, the AEMWE device equipped with a Cu/Ni@MoO 2 cathode achieves the industrial-relevant current densities 1.74 A cm −2 and 3.61 A cm −2 at the voltages of only 1.8 V and 2 V (60 °C), respectively, while demonstrating exceptional durability with negligible voltage decay throughout 1000 h operation at 0.5 A cm −2 . This work presents a novel design strategy for high-current-density electrocatalysts, bridging atomic-scale insights and industrial hydrogen production requirements.