Design and fabrication of intermetallic NiCo electrocatalysts for alkaline HER

Abstract

The design and fabrication of highly efficient electrocatalysts are crucial for reducing energy consumption, improving hydrogen production rate, and prolonging the service life of alkaline electrolyzers. In this study, the intermetallic L10-NiCo electrocatalysts were designed using DFT calculation and fabricated through a one-step solid-state reaction method. The DFT calculation indicated that L10-NiCo presented a lower H adsorption Gibbs free energy and a moderate H2O dissociation barrier compared to the commonly used Ni catalyst and disordered NiCo alloy. Increasing the solid-state reaction temperature facilitated the formation of intermetallic L10-NiCo. Electrocatalytic tests for alkaline HER demonstrated that the ECSA of L10-NiCo nanoparticles increased to 2.3 times, the overpotential decreased by 19%, the electrocatalytic activity increased to 1.5 times, and the stability improved to 2.2 times compared to the Ni nanoparticles. This research provides insights into the design and fabrication of highly efficient catalytic electrodes for alkaline electrolyzers.