Modulating Support Effect in High‐Entropy Sulfide via La Single‐Atom for Boosted Oxygen Evolution

Abstract Reduced energy barrier induced enhanced oxygen evolution reaction (OER) kinetics can be achieved by implementing an efficient electrocatalyst. Herein, positive effect of lanthanum (La) single‐atom modified hollow carbon sphere (HCS) support on OER activity of high‐entropy sulfide (HES) material (FeCoNiCrCuAl)S has been reported. Briefly, La single‐atom boosts the aggregation of electrons at adjacent Fe, Co, Ni, Cr, and Cu sites and dissipation of electrons at Al site in HES material, facilitating reconstruction of electronic structure and down‐shifting their d‐band center away from Fermi level, resulting in reduced adsorption energy of OER intermediates. As developed (FeCoNiCrCuAl)S@La‐HCS depicts high OER performance with an overpotential of only 297 mV at 100 mA cm −2 , surpassing (FeCoNiCrCuAl)S@HCS (324 mV) and commercial RuO 2 catalyst (419 mV). This work provides an insight into the integration of single atom with high‐entropy sulfide toward efficient oxygen evolution.