Highly Efficient and Stable Bifunctional Co ₃ Ni ₆ S ₈ for Electrocatalytic Oxidation of Benzyl Alcohol and Facilitation of Hydrogen Production

The electrocatalytic oxidation of benzyl alcohol (BAOR) is crucial for promoting green industrial oxidation processes and enhancing the yield and productivity of high-value chemicals. However, there are challenges in this field, such as difficult oxidation steps in alkaline electrolytes, slow reaction kinetics, and difficulty in preserving the activity of catalysts during long-term catalytic reactions. Addressing these issues and achieving synergistic reactions to improve energy utilization by combining hydrogen evolution with enhanced catalyst activity and stability warrants focused investigation. Herein, the study reports a Co₃Ni₆S₈-based catalyst, Co_0.33Ni_0.67S₁-10c, which can achieve the oxidation of benzyl alcohol (BA) in alkaline solution for over 350 h, with a conversion rate of BA exceeding 90% and a Faraday efficiency of benzoic acid (BAA) exceeding 99%. The hydrogen production capacity of Co_0.33Ni_0.67S₁-10c is also evaluated in both three-electrode and dual-electrode systems. In the three-electrode system, the hydrogen evolution rate is enhanced by a factor of 9.59 compared to the absence of BA, while in the dual-electrode system, the rate is increased by a factor of 7.85. This work presents a highly efficient and durable catalyst for the oxidation of BA and its synergistic integration with hydrogen production.