Multiscale regulation of S, N, O tri-doped carbon/Co8FeS8 catalysts with SO42−-riched and lattice distortion for efficient water splitting

Abstract

Heteroatom configuration, lattice engineering, and cation–anion modulation are important factors affecting the performance of catalysts for water splitting. However, simultaneously achieving multi-scale regulation of the catalyst represents a formidable challenge. For this problem, we constructed S, N, O triple-doped carbon/Co₈FeS₈ catalysts with SO₄²⁻-riched and lattice distortion (SNO-C/Co₈FeS₈) via a deep eutectic solvent (DES) strategy. SNO-C/Co₈FeS₈ demonstrates outstanding performance in both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) with overpotentials of 230 mV and 120 mV at a current density of 10 mA cm⁻², respectively. Additionally, the theoretical calculations reveal that the remarkable HER/OER dual-function catalytic activity of SNO-C/Co₈FeS₈ primarily stems from the synergistic electronic modulation of sulfate and the carbon matrix on Fe and Co sites. This regulation optimizes the binding of the adsorption capacity of the intermediate, thereby accelerating the kinetics of the HER and OER. This study presents a multi-scale regulation catalyst strategy for fabricating high-performance electrocatalysts.