A high-efficiency oxygen evolution electrocatalyst based on a Co3[Co(CN)6]2@NiFe LDH composite material

Abstract

Due to the slow kinetics and large overpotential of the oxygen evolution reaction (OER) in electrochemical water splitting, it is important to develop efficient and low-cost electrocatalysts for the OER. In this work, we used Co-PBA as the substrate, and induced the growth of NiFe-LDH on the surface of cubic Co-PBA by the hydrothermal method. The Co-PBA@NiFe-LDH electrocatalysts with a flower-like morphology and heterostructures were finally utilized to evaluate the OER performance. The results reveal that during the OER process, the flower-like structure allows Co-PBA@NiFe-LDH-30 to expose more active centers, and increases the contact area between the electrolyte and active sites. Meanwhile, benefiting from the synergistic effect of multi-metals and the heterostructure, Co-PBA@NiFe-LDH-30 demonstrated remarkable electrochemical performance with a lower overpotential of 253 mV at 10 mA cm⁻² and a smaller Tafel slope of 54 mV dec⁻¹. This design strategy provides a promising approach for the development of OER electrocatalysts in the future.