NiFeCo alloy nanoparticles composited with phosphorus-doped vacancies-abundant carbon substrates as electrocatalyst for oxygen evolution reaction

Transition metal alloy nanoparticles are cost-effective electrocatalysts for oxygen evolution reactions. Preparing alloy catalysts with flexible controllability, high activity, and long-term stability is a challenge. By adjusting the proportion of metal atoms and engineering vacancies through their composite with a carbon substrate, we can enhance electron transfer and modulate the adsorption capacity of reaction intermediates. Herein, we synthesized a hybrid catalyst using Prussian blue analogs (PBAs) as the precursor, doped with Fe and Ni atoms, and subjected them to a defective engineering and phosphatization process. As an efficient alkaline OER electrocatalyst, the formation of the alloy increases the number of active sites, while the defect-rich phosphorus-doped carbon substrate improves internal electron transfer and mass transfer channels. The synthesized NiFeCoPC-1.5 electrocatalyst exhibits excellent catalytic activity with an overpotential of 211 mV at 10 mA cm−2 and a Tafel slope of 59 mV dec−1, and demonstrates good stability up to 1000 CV cycles. This work will expand the application of alloy nanoparticles in oxygen evolution electrodes. •Defect engineering through zinc volatilization significantly enhances the OER activity of the material.•The optimal process conditions for the phosphorization of carbon-coated NiFeCo alloy were explored.•In-situ grown carbon shell/carbon nanotubes/carbon substrate can enhance stability.•The effect of different metal source mass ratios on the electrocatalytic performance of the prepared samples was investigated.