Enhancement on PrBa_0.5Sr_0.5Co_1.5Fe_0.5O₅ Electrocatalyst Performance in the Application of Zn-Air Battery

Abstract

Due to the insufficient stability and expensive price of commercial precious metal catalysts like Pt/C and IrO2, it is critical to study efficiently, stable oxygen reduction reaction as well as oxygen evolution reaction (ORR/OER) electrocatalysts of rechargeable Zn-air batteries. PrBa0.5Sr0.5Co1.5Fe0.5O5 (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 O2-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.

Keywords

• PrBa_0.5Sr_0.5Co_1.5Fe_0.5O₅
• double perovskite
• ORR
• OER
• rechargeable Zn-air battery