Sb2S3 nanoparticles anchored on N-doped 3D carbon nanofibers as anode material for sodium ion batteries with improved electrochemical performance

Abstract

Antimony sulfides, owing to their high theoretical specific capacity, are considered promising anode materials for sodium-ion batteries (SIBs). However, antimony sulfides suffer from inferior rate performance and rapid capacity fading due to the poor conductivity and structural instability of their intrinsic physical characteristics in SIBs. Here, a two-step concise method is reported to synthesize antimony sulfide composite structures with Sb2S3 nanoparticles anchored on N-doped 3D carbon nanofibers (SNCFs). The N-doped 3D carbon nanofibers (NCFs) were prepared by electrospinning, and then the Sb2S3 nanoparticles were grown on NCFs by an in situ ultrasonic-assisted method. Benefitting from the synergistic effects between Sb2S3 nanoparticles and NCFs, the SNCFs show a high capacity and long lifespans in SIBs. The as-prepared SNCFs provide a specific capacity of ~412 mAh g−1 after 50 cycles with a current density of 50 mA g−1, which is ascribed to the enhanced transfer of electrons and ions resulted in the high electrical conductivity, good structural integrity and favorable binding energy between Sb2S3 nanoparticles and NCFs.