Sawtooth‐edged zeolitic imidazolate framework codoped with Fe and Co as a bifunctional oxygen electrocatalyst for rechargeable liquid/solid zinc‐air batteries

Because of the practical applications for nonprecious-alloy catalysts in industrial production, zinc-air batteries (ZABs) must be urgently developed to design dual-function electrocatalysts with excellent performance, low price, and facile production steps. This study proposed a newly developed iron, cobalt, and zinc coordination zeolite imidazole skeleton (FeCo-ZIF), which does not require an additional carbon source and reduces environmental pollution. A flake fluffy structure was formed after pyrolysis enhanced metal particle dispersion. Compared with industrial Pt/C (0.837 V half-wave potential) and RuO2 (overpotential), novel Fe-Co-N-C-900 improved oxygen reduction (0.859 V half-wave potential), and oxygen precipitation (343 mV overvoltage at 10 mA cm−2) characteristics because the combination of Fe and Co favoured bifunctional properties. Liquid and solid ZABs are prepared using Fe-Co-N-C-900 as an air cathode. Experimental results showed that liquid ZABs present a higher peak power density (125 mW cm−2) and are steadier during cycling than traditional Pt/C + RuO2 catalysts. Liquid and flexible rechargeable ZABs attained the open-circuit voltages of 1.460 and 1.476 V, respectively. This simple synthesis strategy can provide a novel approach to preparing dual-function catalysts with energy storage and conversion applications.