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

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 24 h from a mixture corresponding to Si:C=3:2 also exhibits a stable capacity of 370 mAh/g. Transmission electron microscopy (TEM) analysis shows that SiC nanocrystallites 10 nm 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.