Construction of Core@Shell Ir-FeSe@CoNiFeSe by Interface Engineering in Conjunction with Atomic Doping for Enhanced Oxygen Evolution Reaction

Interface engineering in conjunction with atomic doping has emerged as a powerful paradigm for constructing highly efficient catalysts for the oxygen evolution reaction (OER). Herein, we design Ir-doped FeSe@CoNiFeSe (Ir-FeSe@CoNiFeSe) as an efficient OER catalyst that integrates a triple-synergistic effect of "core@shell confinement-heterointerface-atomic doping". The strong interactions between the FeSe core and CoNiFeSe shell endow the catalyst with abundant active sites. Moreover, the favorable Ir doping promotes charge transfer and modulates the electronic structure of the Co/Ni/Fe sites, significantly accelerating the reaction kinetics and enhancing the conductivity. Collectively, benefiting from the hollow core@shell structure, effective Ir doping, and abundant active sites at the heterointerfaces, the Ir-FeSe@CoNiFeSe exhibits remarkable OER performances in alkaline media, delivering a lower overpotential of 209 mV at 10 mA cm^-2 and maintaining exceptional durability beyond 70 h. In the two-electrode configuration, an Ir-FeSe@CoNiFeSe anode coupled with a Pt/C cathode sustains an overall water splitting at 10 mA cm^-2 over 45 h with a cell voltage of only 1.44 V, lower than the benchmark RuO₂//Pt/C (1.58 V). This work not only validates the synergistic effect of the "core@shell confinement-heterointerface-atomic doping" in electrocatalysis but also underscores the promising prospect of combining interface engineering with atomic doping to enhance electrocatalytic performance.