Understanding the mechanism and synergistic interaction of cobalt-based electrocatalysts containing nitrogen-doped carbon for 4 e− ORR

Abstract

Considering that the cathodic oxygen reduction reaction (ORR) is sluggish, it is necessary to develop efficient and durable catalysts to accelerate this reaction. Furthermore, the high cost and low abundance of Pt, which is the benchmark catalyst for the cathodic ORR, limit its widespread applications. Among the transition metals, cobalt-based materials have shown significant advancement for the reduction of oxygen molecules, which has been proven by both experimental and theoretical investigations. The high inherent catalytic ability of cobalt among the first row transition metals is the key descriptor for the widespread research in this area. Herein, we review the recent advancements in cobalt-based electrocatalysts supported on nitrogen-doped carbon towards the selective 4 e⁻ reduction of oxygen molecules with enhanced operational durability. Furthermore, we highlight the relationship between theory and experiment to investigate the fundamental mechanism of these electrocatalysts. Finally, we present perspectives on suitable approaches for interpreting the mechanism of cobalt-based nitrogen-doped carbon towards the ORR.