Template-assisted synthesis of single-atom catalysts supported on highly crystalline vanadium pentoxide for stable oxygen evolution

Single-atom catalysts (SACs) have drawn considerable attention due to their maximum atomic catalyst utilization, unique electronic properties, and high cost efficiency, but they tend to aggregate during synthesis, and corrosive carbonaceous supports gradually degrade their original performance. Herein, we develop a template-assisted synthesis of Co SACs anchored on highly crystalline V₂O₅·nH₂O nanobelts (CoVO NBs) for achieving highly stable oxygen evolution reaction (OER). The Co sites on oxide supports weaken the binding energy of reaction intermediates and work as active reaction sites. Even though the partial leaching of V⁴⁺ ions was observed during electrocatalysis, the remaining Co moieties helped to maintain high OER activity and exceptional durability, with initial overpotentials of 428 and 374 mV observed at 10 mA cm⁻² in 0.1 and 1 M KOH, respectively. Furthermore, zinc (Zn)–air cells with CoVO30 NBs displayed a small initial charge-discharge polarization gap (0.78 V) and high cycling performance up to 450 h.