Mesoporous, Si/C composite anode for Li battery obtained by ‘magnesium-thermal’ reduction process

Mesoporous silicon was synthesized by a ‘one spot’ magnesium-driven reduction reaction from SBA-15 mesoporous silica template and, in turn, carbon coated in order to confer it electronic conduction. Mesoporous Si/C composite material shows good electrochemical performances and cycle reversibility when used as anode in a lithium-ion battery. In particular, we found an initial discharge capacity of about 1500 mAhg− 1 at 0.1 C (= 420 mAg− 1), which tend at a plateau at around 600 mAhg− 1 after 100 cycles with an excellent coulombic efficiency. These encouraging results, albeit preliminary, let us forecast that the mesoporous Si/C composite nanostructured material here reported can be a competitive candidate in the arena of the alternative anodic materials proposed for high capacity lithium batteries due to the relative easiness of its preparation and its promising good electrochemical performances.

► Mesoporous, nanostructured Si/C composite powders have been synthesized by a simple magnesio-thermal reduction process.
► Lithium-ion battery anodes prepared out of these powders show high specific capacity and good electrochemical performances.
► The carbon presence improves the anode electronic conductivity and helps in preventing large Si volume variations.