Preparation of NiFeCr-based trimetal organic frameworks as electrocatalyst for direct use in oxygen evolution reaction

The development of high-efficiency electrocatalysts for oxygen evolution reaction (OER) is of great significance to the further development of hydrogen energy. In recent years, metal organic frameworks (MOFs) have become an excellent electrocatalyst due to its characteristics. NiFeCr-MOFs were synthesized and prepared in one step by simple solvothermal method, which improved the OER performance compared with NiFe-MOFs. When the doping dosage of Cr3+ is 0.3 mmol, the performance of ternary MOFs is optimal, requiring only 333 mV overpotential to provide a current density of 10 mA/cm2, and the slope of Tafel is only 66 mV dec−1. In this paper, the role of Cr3+ in the catalyst and the reason and mechanism for the improvement of OER performance were studied from the aspects of electrochemical surface area (ESCA), electrochemical impedance spectroscopy (EIS) and electronic structure of the catalyst. Experiments have proved that the preparation of ternary MOFs by co-doping with an appropriate amount of Ni, Fe, and Cr has practical significance for improving the performance of OER.