Electrospinning of GeO2–C fibers and electrochemical application in lithium-ion batteries

GeO2–C fibers were successfully synthesized using electrospinning homogeneous sol and subsequent calcination in an inert atmosphere. The spinnable sol was prepared by adding polyacrylonitrile (PAN) and polyvinylpyrrolidone (PVP) in a weight ratio of 1:1 into a mixture with white precipitate produced by dropping GeCl4 into DMF. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to characterize the as-obtained fibers, and electrochemical tests were conducted to measure electrochemical performance of the electrode. The electrospun fibers have uniform diameters of ∼300 nm. After being calcined at 600 °C for 2 h in Ar, they transform to amorphous GeO2–C fibers with the same morphologies. The GeO2–C fibers exhibit excellent cycling stability with a high reversible capacity of 838.93 mA h g−1 after 100 cycles at a current density of 50 mA g−1, indicating the composite fibers could be promising anode candidates for lithium-ion batteries.

Graphical abstractThe electrospun GeO2–C composite fibers with diameters of ∼300 nm and amorphous structures exhibit high specific capacity and excellent cyclic performance, which make them promising anode candidates for lithium-ion batteries.Figure optionsDownload full-size imageDownload as PowerPoint slide