The synergetic effect at the interfaces between metal oxide and metal in heterostructures plays an essential role in electrocatalytic hydrogen production via water electrolysis. Here, a micro-nanoporous MoO₂@CoMo heterostructure with high catalytic performance was simply fabricated electrochemically at room temperature and under ambient pressure. Controllable microporous CoMo networks were formed on the gas diffusion layer using hydrogen bubble-assisted electrodeposition. The following electrochemical etching at an appropriate potential produced a nanoporous surface via selective Co dissolution, accompanied by the formation of Mo oxide. Due to the significantly roughened morphology and the interfacial effect, the optimized MoO₂@CoMo heterostructure catalyst exhibited a low overpotential of 76 mV for hydrogen evolution at −50 mA/cm². Further analysis verified the crucial role of the Mo⁴⁺ ratio in the intrinsic activity. The insoluble Mo species passivated the MoO₂ surface layer and sustained the Mo⁴⁺ ratio, leading to excellent stability of the MoO₂@CoMo heterostructure catalyst in long-term operation.

在异质结构中金属氧化物和金属之间的界面上的协同作用在通过水电解产生电催化制氢中起着至关重要的作用。在此，具有高催化性能的微纳孔MoO ₂ @CoMo异质结构是在室温和环境压力下简单地电化学制备的。使用氢气气泡辅助电沉积在气体扩散层上形成可控的微孔CoMo网络。随后在适当电势下进行的电化学蚀刻通过选择性的Co溶解产生了纳米孔表面，并伴有Mo氧化物的形成。由于明显的粗糙化形态和界面效应，优化的MoO ₂在-50mA / cm ^2下， @ CoMo异质结构催化剂对于氢析出表现出76mV的低过电势。进一步的分析证实了Mo ⁴⁺比率在固有活性中的关键作用。不溶性Mo物种钝化了MoO ₂表面层并维持Mo ⁴⁺比率，从而导致MoO ₂ @CoMo异质结构催化剂在长期运行中具有出色的稳定性。