Self-Supporting Silicon-Based Hierarchical Carbon Nanofibers as Anodes for Lithium-Ion Batteries

Abstract

Silicon-based electrodes demonstrate significant potential for application in lithium-ion batteries (LIBs) due to their high-energy density. However, the commercial use of silicon-based materials is hindered by their substantial volume expansion and poor electrical conductivity. Therefore, self-supporting silicon-based hierarchical carbon nanofibers (Si@SiOx/HPCNFs) as high-performance anodes for LIBs were fabricated using a coaxial electrospinning technique in this paper. By introducing an oxide layer onto the surface of silicon nanoparticles, the volume expansion of silicon was alleviated, and sufficient hydrogen bonds and active sites were provided for the adequate binding between Si@SiOx and precursors. The hierarchical carbon framework prevented direct contact between silicon and electrolyte, reducing Li+ diffusion distance and facilitating ion transport. Si@SiOx/HPCNFs anode exhibited a high reversible capacity of 686.0 mAh g-1 after 100 cycles at 100 mA g-1. Moreover, Si@SiOx/HPCNFs anode retained its original fiber structure even after 100 cycles, suggesting that the self-supporting Si@SiOx/HPCNFs electrode have great potential in advanced energy storage.

Keywords: Coaxial electrospinning, Hierarchical structure, Self-supporting carbon nanofibers, Lithium-ion battery, Silicon anode