FeZrRu Trimetallic bifunctional oxygen electrocatalysts for rechargeable Zn-air batteries

The development of high active and stable bifunctional electrocatalysts for metal-air batteries remains a challenge due to the slow reaction kinetics both in oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Herein, a trimetallic electrocatalyst with efficient ORR and OER bifunctional catalytic activities has been fabricated by a one-step high-temperature pyrolysis methodology. The catalyst shows higher catalytic ORR and OER performance than the commercial 46% TKK platinum carbon and IrO₂ catalysts, respectively, with a half-wave potential (E_1/2) of 0.912 V vs. RHE for ORR in 0.1 M KOH and an overpotential of 250 mV at 10 mA/cm² for OER in 1 M KOH. Moreover, the carbon encapsulation ensures the high stability of FeZrRu/C catalysts both for both ORR and OER electrocatalysis. The Zn–air batteries using the obtained FeZrRu/C catalysts exhibit a power density as high as 221.34 mW/cm². This work provides a universal strategy for the synthesis of high-performance trimetal-doped bifunctional electrocatalysts for metal-air batteries and fuel cells.