Novel Route to Fe‐Based Cathode as an Efficient Bifunctional Catalysts for Rechargeable Zn–Air Battery

Abstract

Abstract Efficient bifunctional oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalysts are of great importance for rechargeable metal–air batteries. Herein, FeN x /C catalysts are synthesized by pyrolysis of thiourea and agarose containing α‐Fe 2 O 3 nanoplate as Fe precursor, where α‐Fe 2 O 3 nanoplate can prevent the aggregation of carbon sheets to effectively improve the specific surface area during the carbonization process. The FeN x /C‐700‐20 catalyst displays excellent catalytic performance for both ORR and OER activity in alkaline conditions with more positive onset potential (1.1 V vs the reversible hydrogen electrode) and half‐wave potential, higher stability, and stronger methanol tolerance in alkaline solution, which are all superior to that of the commercial Pt/C catalyst. In this study, the detailed analyses demonstrate that the coexistence of Fe‐based species and high content of Fe‐N x both play an important role for the catalytic activity. Furthermore, FeN x /C‐700‐20 as cathode catalyst in Zn–air battery possesses higher charge–discharge stability and power density compared with that of commercial Pt/C catalyst, displaying great potential in practical implementation of for the rechargeable energy devices.