Structure deformation of Ni–Fe–Se enables efficient oxygen evolution via RE atoms doping

The development of cost-effective and highly stable electrocatalysts for oxygen evolution reactions holds paramount importance in practical hydrogen production. Herein, we present a novel self-supported electrode comprising Ce-doped Ni–Fe–Se nanosheets grown on carbon cloth (Ni–Fe–Ce–Se/CC). This electrode was synthesized through a selenylation process, utilizing Ni–Fe-Ce-layered double hydroxide/carbon cloth (Ni–Fe–Ce LDH/CC) as the precursor. Notably, Ni–Fe–Ce–Se/CC electrode demonstrates remarkable performance, requiring a low overpotential of 300 mV to attain a current density of 100 mA· cm⁻² under harsh alkaline conditions. Furthermore, the electrode exhibits exceptional stability during continuous operation for 100 h. Insight into the underlying mechanisms was gained through a combination of experimental results and density functional theory calculations. Our findings reveal that Ce doping induces crystal structure deformation in Ni–Fe–Se and enhances electron enrichment around Ni atoms. This structural modification optimizes the adsorption energy of oxygen-based intermediates on the Ni–Fe–Se surface. This work offers a valuable strategy for regulating the electron transfer and adsorption capabilities of transition metal selenide electrocatalysts through RE atoms doping, opening new avenues for enhanced electrocatalytic performance.

Graphical abstract