Dynamic Investigations on CoFe2O4@Co3O4 Nano-composite as an Enhanced Electrocatalyst for Oxygen Evolution Reaction

The oxygen evolution reaction (OER) holds pivotal importance in sustainable energy conversion, as it forms the critical half-reaction in various electrochemical processes, including water splitting for hydrogen production and rechargeable metal-air batteries. Here, a CoFe2O4@Co3O4 nano-composite was synthesized using a facile hydrothermal process and deposited onto the surface of nickel foam through electrophoresis. Characterization using XRD, Raman spectroscopy, and XPS confirmed the successful synthesis of the composite, exhibiting characteristic peaks of both Co3O4 and CoFe2O4. The nano-composite exhibited a more amorphous phase than pure oxides, benefiting electrocatalytic activity. Scanning and transmission electron microscopy highlighted the composite's morphological characteristics, showcasing a Co3O4 island distribution on the CoFe2O4 surface. Electrochemical evaluations revealed the superior oxygen evolution reaction (OER) performance of CoFe2O4@Co3O4, with low overpotentials, faster kinetics, and enhanced stability compared to pure oxides and the benchmark RuO2 catalyst. A comprehensive analysis was carried out to investigate the dynamic behavior during electrocatalytic oxygen evolution reaction. This study unveils the intricate charge and electron transfer mechanisms between cobalt and iron atoms, providing insights into their collaborative role throughout the OER process.