Zeolitic Imidazolate Framework Film Derived CoFe‐N‐C Nanofoams for Reliable Zn‐air Batteries

Abstract

Abstract The design of the efficient, flexible air electrode for enhancing the Zn‐air batteries (ZABs) performance is vital in developing a new portable rechargeable power supply. Emerging research indicates that non‐precious metal materials have promising activity for oxygen reduction/evolution in alkaline conditions while constructing a high‐performance and reliable electrode is still a big challenge at the present stage. In this work, a bimetal doped zeolitic imidazolate framework (ZIF) film is synthesized by fast current‐driven synthesis (FCDS) on a thin carbon nanotube film (CNTF). After carbonization at 950 °C, CoFe‐N‐C nanofoam formed on the CNTF, resulting in binder‐free, flexible electrodes. It exhibits excellent activity and stability toward oxygen reduction and evolution. The CoFe‐N‐C/CNTF‐based liquid‐state ZAB shows an output power density of 294 mW cm−2. When applied in solid‐state ZAB, the flexible battery shows high power density and excellent cycling stability.

Keywords

• binder‐free air electrode
• CoFe‐N‐C nanofoam
• fast current‐driven synthesis
• zeolitic imidazolate framework film
• Zn‐air batteries