Hierarchical CuO@Ni/NiO nanoarchitectures with dual synergistic effects for industrial high-current-density hydrogen evolution

The development of efficient and durable non-precious metal catalysts for hydrogen evolution reaction (HER) remains a significant challenge. In this work, we present a novel approach combining heterojunction and structural engineering to enhance HER performance. A NiO/Ni layer with a heterogeneous structure is grown on CuO nanorod arrays supported by copper foam. This 3D nanostructure increases the density of active sites, improves mass and electron transport, and accelerates HER kinetics. The rough surface also facilitates rapid bubble release, enhancing catalyst stability under high currents. As a result, the CuO@NiO/Ni catalyst exhibits excellent HER performance, with overpotentials of 86.5 and 198.8 mV at 100 and 500 mA cm −2 , respectively. Additionally, a two-electrode electrolytic cell using CuO@NiO/Ni and NiFe LDH achieves 500 mA cm −2 at only 1.64 V and maintains excellent stability over 100 h. These findings highlight the potential of CuO@NiO/Ni as a highly efficient, stable catalyst for industrial-scale water electrolysis, and provide a promising approach to addressing the challenges of non-precious metal-based HER catalysts in industrial settings.