ABSTRACT Advancing flexible zinc‐air batteries requires cost‐effective, durable bifunctional catalysts capable of efficiently driving both oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). Here, we report a scalable reflux‐calcination strategy to prepare hierarchical flower‐like Fe–Mo oxides (FeMoO). The engineered Fe–O–Mo interactions effectively tune the electronic structure, lower adsorption energy barriers, and accelerate charge‐transfer kinetics. Among the series, Fe 0.25 Mo 0.75 O (FeMoO‐III) exhibited excellent OER activity with an overpotential of 240 mV at 10 mA cm −2 and remarkable stability exceeding 200 h at 50 mA cm −2 . Concurrently, ORR studies revealed a high half‐wave potential (0.86 V) and outstanding durability, confirming its bifunctional performance. When integrated into a rechargeable zinc‐air battery, FeMoO‐III delivered a high open‐circuit voltage of 1.51 V and sustained charge–discharge cycling over 175 h. Moreover, in a flexible quasi‐solid‐state zinc‐air battery, the FeMoO‐III cathode maintained stable operation for more than 56 h at 5 mA cm −2 , underscoring its suitability for wearable energy devices. This work demonstrates that rational modulation of non‐noble oxide electronic structures through Fe–Mo synergy offers a practical pathway toward scalable, high‐performance, and flexible zinc‐air batteries.
Subramanian et al. (Thu,) studied this question.