Preparation and performance of Co-Mo nano metal oxide electrocatalyst for hydrogen production by electrolysis of water

• The performance of CoNiMoOx is most impacted by the doping ratio and work temperature. • Uniform nanostructures in CoNiMoO x catalysts offer ideal active site exposure. • Slow heating is conducive to improve the crystal phase stability. • CoNiMoO x electrocatalysts perform optimally when Mo:Co mass ratio is ≤ 1. Hydrogen production by green electricity electrolyzing water is a burgeoning technology inrecent years. The efficiency of hydrogen production is significantly influenced by the performance of catalysts in the electrolyzer. This research delves into the effects of the Mo and Co doping ratio, reaction parameters, and heating rate on catalyst performance. A series of systematic experiments elucidates how these variables impact the structure and electrochemical efficacy of the catalyst. The CoNiMoO x catalysts exhibited enhanced charge transfer characteristics when the Mo:Co mass ratio was 1:2, leading to improvements in electronic structure and active site distribution. Optimal preparation conditions, sunch as a 1℃/min heating process to 120 °C over a period of 3 h, resulted in better catalyst crystallinity, stability, electrochemical activity, and longevity. Analyses utilizing scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) confirmed a more homogeneous nanostructure and increased specific area under these optimized preparation conditions. Electrochemical evaluation further showed that the overpotential of HER was reduced by 30 % and that of OER was reduced by 15 % with the optimized catalyst. This investigation furnishes a crucial experimental foundation and theoretical underpinning for the development and synthesis of highly efficient electrocatalysts.