Enhanced Hydrogen Evolution Reaction Kinetics by Sulfur Incorporation in Transition Metal-Based Oxyhydroxide Electrodes

Hydrogen, with its high energy density and sustainability, is a promising energy carrier, and water electrolysis provides an efficient, carbon-free method for its production. To achieve cost-effective hydrogen production, the development of transition metal-based hydrogen evolution reaction (HER) electrocatalysts is crucial. In this study, A sulfur-doped NiFeCo(oxy)hydroxide electrode (S-NiFeCo/NF) for HER was prepared using galvanic corrosion and hydrothermal methods. Sulfur incorporation modulated the electronic structure, lowering the overpotential (from −252 mV at −10 mA/cm ² to −115 mV at −10 mA/cm ² ) and activation barrier (from 142 kJ/mol to 56kJ/mol). The S-NiFeCo/NF electrode also demonstrated remarkable durability, with only 0.13 mV/h degradation in activity over 400 hours at −100 mA/cm ² , highlighting sulfur doping as an effective strategy for non-precious HER electrocatalysts.