Interfacial electronic modulation and coupling of NiFe LDH via α-Co(OH)2 for enhanced oxygen evolution

NiFe-layered double hydroxides (NiFe LDHs) are regarded as outstanding electrocatalysts for the oxygen evolution reaction (OER), but the inherent charge transport limitations hinder their practical application. Herein, we developed a 3D hierarchical α-Co(OH) 2 /NiFe LDH/NF composite catalyst via a simple electrodeposition-hydrothermal method. The introduction of α-Co(OH) 2 enables interfacial electron modulation with NiFe LDH, driving electron transfer from Ni/Co sites to Fe centers via multi-pathway coupling channels (Ni–O–Fe, Ni–O–Co, Co–O–Fe). This electron redistribution creates an optimized coordination environment that promotes the formation of high-valence Ni and Co species, subsequently facilitating the in situ formation of highly active phases (γ-NiFeOOH and CoOOH) during the OER process. The derived γ-NiFeOOH provides superior intrinsic activity, while the coexisting. CoOOH significantly enhances charge transport due to its high electronic conductivity. As a result, the composite achieves an overpotential of only 285 mV at a current density of 500 mA cm −2 , outperforming both NiFe LDH (372 mV) and α-Co(OH) 2 (441 mV). Additionally, this catalyst shows an excellent long-term stability at 100 mA cm −2 for 120 h. This work demonstrates that interfacial electronic modulation offers a strategy for designing efficient and durable OER catalysts capable of operating at industrial current densities.