Synchronously synthesized Si@C composites through solvothermal oxidation of Mg2Si as lithium ion battery anode

Si@C composites have been solvothermally synthesized by the reaction of ethanol or acetone with Mg2Si at 650 degrees C, followed by HCl washing. Ethanol or acetone can oxidise Mg2Si to form Si, and at the same time, they are reduced to synchronously form carbon coated on the surface of the generated Si nanoparticles. As lithium ion battery anode, the as-synthesized Si@C composites obtained from the reaction of acetone with Mg2Si deliver a reversible capacity of 3277 mA h g(-1) at 0.36 A g(-1) and remain 892 mA h g g(-1) at 3.6 A g(-1) after 350 cycles.