Interfacial engineering of RuO2/CoOOH heterojunction for efficient oxygen evolution reaction

Abstract

Rational design and construction of low-cost and efficient catalysts with robust structures are significant toward oxygen evolution reaction (OER), but their scalable synthesis remains a grand challenge. Herein, we report a combustion-assisted strategy for in situ growth of a RuO₂/CoOOH heterojunction on cobalt foam, which can serve as both metal source and catalyst support. This simple route is favorable to large-scale industrial applications for hydrogen production in the future. Due to the synergistic effect of catalytically active phases, abundant heterointerfaces, and 3D porous structures, the targeted catalyst shows outstanding catalytic OER performance with a lower overpotential of 190 mV to reach a current density of 10 mA cm⁻², smaller Tafel slope of 47.5 mV dec⁻¹, and long-term durability for 50 h in 1.0 M KOH solution. When assembled as the anode toward full water splitting, the electrolyzer is capable of offering 10 mA cm⁻² at a cell voltage of 1.47 V along with remarkable operational stability. Moreover, the device can be powered by a 1.5 V AA battery, wind, and solar energies, respectively. This work offers a feasible, rapid, and scalable approach for fabricating efficient robust catalysts for oxygen electrocatalysis.