Controling surface reconstruction of transition metal-hydroxide organic framework to enhance the stability of oxygen evolution reaction

Abstract

The surface reconstruction of the electrocatalysts often occurs in the oxygen evolution reaction (OER), which inevitably leads to the deterioration of stability. Hence, Ce-doped transition metal-hydroxide organic frameworks (Ce-TMHOF) with varying molar ratios of Ce were synthesized using a simple one-step hydrothermal method. The 21%Ce-TMHOF exhibited overpotentials of 200 and 240 mV to achieve current densities of 10 and 100 mA cm−2, respectively. Moreover, it maintained a remarkable efficiency of 98.3% after 110 h of stability testing during the OER process. When incorporated into an anion exchange membrane (AEM) electrolyzer alongside commercial Pt/C electrocatalysts, the 21%Ce-TMHOF maintained an efficiency of 98.8% even after 500 h of testing. Our findings suggest that 4f orbital electron of Ce induce charge redistribution through electronic coupling with Ni and Fe, thereby mitigating surface reconstruction and improving the activity and stability of the electrocatalyst. This study sets a foundation for developing more stable and efficient electrocatalysts for energy storage and conversion applications.