Restricting Growth of Ni3Fe Nanoparticles on Heteroatom-Doped Carbon Nanotube/Graphene Nanosheets as Air-Electrode Electrocatalyst for Zn–Air Battery

Exploring bifunctional oxygen electrode catalysts with efficient and stable oxygen reduction reaction (ORR)/oxygen evolution reaction (OER) performance is one of the limitations for high-performance zinc–air battery. In this work, Ni 3 Fe alloy nanoparticles incorporated in three-dimensional (3D) carbon nanotube (CNT)/graphene nanosheet composites with N and S codoping (Ni 3 Fe/N–S–CNTs) as bifunctional oxygen electrode electrocatalysts for zinc–air battery. The main particle size of Ni 3 Fe nanoparticles could be well restricted because of the unique 3D structure of carbon nanotube/graphene nanosheet composites (N–S–CNTs). The large specific area of N–S–CNTs is conducive to the uniform dispersion of Ni 3 Fe nanoparticles. On the basis of the synergistic effect of Ni 3 Fe nanoparticles with N–S–CNTs, and the sufficient exposure of reactive sites, the synthesized Ni 3 Fe/N–S–CNTs catalyst exhibits excellent OER performance with a low overpotential of 215 mV at 10 mA cm –2, and efficient ORR activity with a half-wave potential of 0.877 V. When used as an electrocatalyst in zinc–air battery, the device exhibits a power density of 180.0 mW cm –2 and long term durability for 500 h.