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

GeO–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 GeClinto 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 8C for 2 h in Ar, they transform to amorphous GeO–C fibers with the same morphologies. The Ge O–C fibers exhibit excellent cycling stability with a high reversible capacity of 838.93 m A h gafter 100 cycles at a current density of 50 m A g, indicating the composite fibers could be promising anode candidates for lithium-ion batteries.