Highly active SiO2@C nanofiber: high rate and long cycling for lithium ion batteries

SiO2-based anodes for lithium ion batteries (LIBs) suffer from low conductivity and volume change in charge/discharge processes. It is reported that reasonable amorphous and nanometric characteristics can effectively improve the activity of SiO2 for Li+ storage. So, highly active SiO2@C nanofibers were prepared by electrospinning. Using X-ray diffraction (XRD), its amorphous characteristics were revealed. The results from scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that it was a nanofiber structure. As an anode for LIBs, the SiO2@C nanofibrous electrode showed the discharge capacities of 675 and 188 mAh g−1 at 1 A g−1 (1000the cycle) and 10 A g−1 (5000th cycle), respectively. Even at 50 A g−1, it still maintained 88 mA h g−1 at 60,000 cycles, showing excellent stability and high rate.