LSCF perovskite oxide in situ grown on reduced graphene oxide as high-performance bifunctional catalyst for zinc-air battery

Perovskite material is a low-cost catalyst with bifunctional catalytic activities for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in the air electrode of zinc-air battery. Herein, a simple sol-gel method is developed to grow perovskite La0.5Sr0.5Co0.8Fe0.2O3-delta (LSCF) on the surface of reduced graphene oxide (rGO) directly, noted as LSCF@rGO. Among different concentrations of rGO, LSCF@rGO-0.50 showed the best bifunctional catalytic activity which E1/2 of ORR and Ej = 10 mA cm-2 of OER are 0.80 V and 1.68 V in 0.1 M KOH solution, respectively. In addition, when LSCF@rGO-0.50 is applied in zinc-air battery, impressive battery performances are obtained, such as maximum power density of 104 mW cm-2, specific capacity of 723 mAh gZn- 1, and cycle stability of over 100 h. This work indicates the possibility of enhancing bifunctional per-formance of perovskite materials with a facile recombination procedure and identifies the potential of LSCF@rGO as an alternative to noble metal materials for air electrodes in zinc-air batteries.