In situ coupling of NiFe nanoparticles with N-doped carbon nanofibers for Zn-air batteries driven water splitting

Abstract A flexible 3D free-standing bifunctional electrode has been successfully constructed by in-situ coupling of NiFe nanoparticles and N-doped carbon nanofibers on carbon cloth (NiFe/NCNF/CC). The 3D network structure is formed by the cross-linking of slender N-doped carbon nanofibers, which provides large specific surface area and ensures fast electron/charge transfer. The in-situ coupling in 3D space of NiFe particles and N-doped carbon nanofibers provide sufficient and stable reactive sites for both OER and ORR. Therefore, NiFe/NCNF/CC electrode exhibits efficient and stable ORR and OER performance. The NiFe/NCNF/CC electrode assembled Zinc-air battery exhibits a high power density of 140.1 mW cm−2 and excellent charge/discharge stability for 700 cycles. Interestingly, the flexible Zinc-air battery delivers flexible and foldable mechanical properties and a low voltage gap of 0.55 V at 1.0 mA cm−2. Furthermore, two liquid Zinc-air batteries are served as stable power for the self-assembled water-splitting device.