Self-Assembled Mace-Like Fe3O4 Nanostructures as a Lithium–Air Battery Cathode Material

Abstract

Mace-like Fe3O4 nanostructures with a length of 200–300 nm and a diameter of 10–30 nm were successfully synthesized via a microemulsion-mediated solvothermal method and used as an electrode catalyst for lithium–air batteries. The results showed that the mace-like Fe3O4 nanostructures were obtained by adjusting the NaOH concentration and reaction temperature, and by adding polyethylene glycol-1000. The growth and assembly mechanism of the mace-like Fe3O4 nanostructures was also discussed. Polyethylene glycol-1000 not only acted as a soft template to form Fe3O4 nanorods, but also assisted in the assembly of the Triton X-100-decorated Fe3O4 nanoparticles onto the nanorods. The results of charge–discharge tests showed that the lithium–air battery based on mace-like Fe3O4 nanostructures exhibited a high discharge capacity of 1427 mA h g−1 in ambient air. The unique one-dimensional mace-like Fe3O4 nanostructures could effectively enhance the catalytic activity for the oxygen evolution reduction process, which is effective for decreasing the charging potential plateau.