Tuning the Wettabilityof Binary Alloy Electrodesto Promote OER Catalysis in Alkaline Media by Group Distribution Ratio

The environmental issues brought about by fossil fuels have shifted people’s focus toward clean energy, and water electrolysis for hydrogen production is considered a viable solution. Binary alloy catalysts have been widely utilized due to their excellent performance. The mechanisms underlying the influence of the composition ratio of binary alloys on catalytic performance seem ambiguous, while the impact of component ratios on the structure of catalysts prepared through electrochemical methods remains unclear. A Ni–Co binary alloy was chosen to investigate the oxygen evolution reaction (OER) performance of the catalytic electrodes prepared under different Ni–Co ratios. Density functional theory calculations show that the synergistic effect generated by an appropriate Ni/Co ratio can accelerate the OER process. Alloy catalytic electrodes with varying Ni/Co molar ratios were prepared using a three-electrode system. Analysis of OER demonstrates that catalytic electrodes containing the same amount of Ni–Co display a minimal overpotential of 288 mV (10 mA cm^–2). Additionally, these electrodes exhibit the least Tafel slope of 60 mV dec^–1. Moreover, these electrodes demonstrate sustained high stability even after 100 h of testing. This study provides an in-depth understanding of the binary alloy ratios’ impact on the OER catalytic performance.