Ga-Induced p–d Orbital Hybridization in CoFe LDH for Boosted Oxygen Evolution Electrocatalysis

Abstract

CoFe-based layered double hydroxides (LDHs) are emerging as prominent candidates for the oxygen evolution reaction (OER) due to their tunable 3d orbital electronic structure but are still restricted by the strong adsorption of oxygen-containing intermediates due to their high antibonding orbital relative to the Fermi level. Herein, we synthesized Ga-doped CoFe LDH (GaCoFe LDH) as a highly effective catalyst for alkaline OER. Experimental and theoretical investigations reveal that the strong p–d orbital hybridization between Ga and Co/Fe atoms plays a critical role in boosting the OER performance. This hybridization not only effectively reduces the antibonding orbital energy levels due to an enhanced electronic filling degree in the antibonding orbital but also facilitates the dehydrogenation of *OH to *O, thereby boosting catalytic activity. Remarkably, GaCoFe LDH exhibits excellent OER performance, surpassing both CoFe LDH and RuO 2 /NF, with low overpotentials of 185 and 242 mV at 10 and 100 mA cm –2, respectively, while maintaining exceptional OER stability.