Rhodium-Modified Cobalt–Organic Framework Structure: An Efficient Bifunctional Catalyst for Stimulate Alkaline Water Splitting

High-efficiency and stable catalysts under alkaline conditions are crucial for advancing an anion exchange membrane (AEM) electrolyzer. In this article, the high inherent catalytic activity of precious metals and the surface defect engineering of MOFs were coupled to construct effective and stable bifunctional catalysts for HER and OER. Rh with superior HER activity was fixed in the prepared Co-MOF, which increased the availability and stability of Rh. Furthermore, the introduction of Rh results in a high concentration of oxygen vacancy of Co-MOF, and hence, the catalyst also displayed excellent OER activity. The overpotentials of Rh15@Co-MOF in HER and OER are 65 mV and 240 mV at 10 mA cm–2, respectively, while it can be stable during the continuous operation for 30 h, respectively. This strategy reduces the consumption of Rh while improving the intrinsic activity and stability of the catalyst, providing feasibility for catalysts that meet the current demands.