Dip-Coated Cobalt Oxide Thin Film: A Facile Approach for Oxygen Evolution Reaction

Abstract

This study presents a low-cost and scalable dip-coating approach for synthesizing nanoparticles of cobalt oxide (Co₃O₄) thin films on stainless-steel substrate and assesses electrochemical performances in alkaline water electrolysis (AWE). Electrochemical assessment via linear sweep voltammetry (LSV) exhibited that the 10L Co₃O₄-coated steel exhibited reduced overpotentials of 258, 350, and 430 mV at current densities of 10, 50, and 100 mAcm^-2, respectively, compared to uncoated steel, highlighting the influence of film thickness on OER performance. The OER activities of the as-synthesized electrocatalyst are due to the intrinsic electronic structure, promising oxidation states of Co, and catalytic properties. This study brings a cost-effective and controllable synthesis approach for cobalt oxide thin films, presenting insights into the influence of layer deposition on electrocatalytic activity.