Channelized carbon nanofiber with uniform-dispersed GeO2 as anode for long-lifespan lithium-ion batteries

The direct use of low-cost GeO2 nanoparticles as a replacement for germanium salt as a source of germanium is more practical for the fabrication of GeO2/C composite electrodes for commercial lithium-ion batteries (LIBs). However, the tendency of nanoparticles to easily agglomerate complicates the task of obtaining a uniform distribution of GeO2 in a carbon matrix. In this study, we used polystyrene (PS) as a sacrificial template to fabricate a uniform dispersion of multichannel carbon fiber with amorphous GeO2 (GeO2/MCNF) via electrospinning with a single nozzle. With a polyacrylonitrile (PAN)/PS ratio of 1:0.6, the GeO2/MCNF composite shows enhanced initial Coulombic efficiency (66.9%), high reversible specific capacity (832 mA h g(-1) after 100 cycles under a current density of 250 mA g(-1)), and excellent cycling stability and rate capability. Especially, this anode material exhibits superior cycling stability (472 mA h g(-1) after 500 cycles under a current density of 1250 mA g(-1)). The improved electrochemical performance could be attributed to the uniformly dispersed GeO2, unique carbon nanostructure, and the synergistic interaction between GeO2 and the CNFs. The proposed method provides a common strategy to develop other low conductivity anode materials with high current capacities and long-term cycle stabilities. (C) 2017 Elsevier B.V. All rights reserved.