| Summary: | Due to the insufficient stability and expensive price of commercial precious metal catalysts like Pt/C and IrO<sub>2</sub>, it is critical to study efficiently, stable oxygen reduction reaction as well as oxygen evolution reaction (ORR/OER) electrocatalysts of rechargeable Zn-air batteries. PrBa<sub>0.5</sub>Sr<sub>0.5</sub>Co<sub>1.5</sub>Fe<sub>0.5</sub>O<sub>5</sub> (PBSCF) double perovskite was adopted due to its flexible electronic structure as well as higher electro catalytic activity. In this study, PBSCF was prepared by the citrate-EDTA method and the optimized amount of PBSCF-Pt/C composite was used as a potential ORR/OER bifunctional electrocatalyst in 0.1 M KOH. The optimized composite exhibited excellent OER intrinsic activity with an onset potential of 1.6 V and Tafel slope of 76 mV/dec under O<sub>2</sub>-saturated 0.1 M KOH. It also exhibited relatively competitive ORR activity with an onset potential of 0.9 V and half-wave potential of 0.78 V. Additionally, Zn–air battery with PBSCF composite catalyst showed relatively good stability. All these results illustrate that PBSCF-Pt/C composite is a promising bifunctional electrocatalyst for rechargeable Zn-air batteries.
|
|---|