Si-SiC nanocomposite anodes synthesized using high-energy mechanical milling

摘要

The Si-SiC nanocomposites were synthesized by high-energy mechanical milling (HEMM) using two different starting mixtures, Si:SiC = 1:2 and Si:C = 3:2. Both mixtures result in amorphous silicon and nanocrystalline silicon carbide as confirmed by XRD results. The Si-SiC nanocomposite corresponding to Si:SiC = 1:2 obtained after milling for 30 h shows a capacity as high as ～370 mAh/g. The nanocomposite synthesized using HEMM for 24h from a mixture corresponding to Si:C = 3:2 also exhibits a stable capacity of ～370mAh/g. Transmission electron microscopy (TEM) analysis shows that SiC nanocrystallites ≈10nm in size are distributed homogeneously within the nanocomposite. Electron energy-loss spectroscopy (EELS) maps of C suggests that SiC is uniformly present within the particles.