Dual-defective-engineered RuO₂/D-Co₃O₄/CC composite as efficient electrocatalysts for triggering oxygen evolution reaction in acidic media

Defect engineering is widely acknowledged as an effective strategy for improving catalyst performance by increasing the abundance of active sites and optimizing binding energies. Herein, dual-defective-engineered RuO₂/D-Co₃O₄/CC composite was fabricated using a straightforward process involving electrodeposition and acid etching method to improve the oxygen evolution reaction (OER) with low Ru loading (2.42 wt%) in acidic media. The RuO₂/D-Co₃O₄/CC catalyst was thoroughly characterized using physicochemical techniques, revealing the presence of both anionic and cationic defects in RuO₂/D-Co₃O₄/CC. Experimental studies demonstrate that the optimized RuO₂/D-Co₃O₄/CC with dual defects enhances the electrochemically exposed active sites and effectively reduces the dependence of the catalytic reaction on the concentration of protons in the electrolyte, thereby triggering high-performance OER. A mere 181 mV overpotential is needed to achieve a current density of 10 mA cm⁻², and it can sustain uninterrupted continuous electrolysis at this current density for 120 h. This characteristic renders it a highly promising electrocatalyst for acidic OER.