Scalable Synthesis of Nano-Silicon from Beach Sand for Long Cycle Life Li-ion Batteries

摘要

Herein, porous nano-silicon has been synthesized via a highly scalable heat scavenger-assisted magnesiothermic reduction of beach sand. This environmentally benign, highly abundant, and low cost SiO₂ source allows for production of nano-silicon at the industry level with excellent electrochemical performance as an anode material for Li-ion batteries. The addition of NaCl, as an effective heat scavenger for the highly exothermic magnesium reduction process, promotes the formation of an interconnected 3D network of nano-silicon with a thickness of 8-10?nm. Carbon coated nano-silicon electrodes achieve remarkable electrochemical performance with a capacity of 1024?mAhg?1 at 2?Ag?1 after 1000 cycles.