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

Abstract

Summary 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.