A low-cost and energy-saving preparation method for silicon derived from rice husks and lithium ion battery applications

Rich husks are used as the raw material for preparation of silicon nanoparticles from an aluminothermic reduction process. The synthetic process is conducted on a low temperature condition, avoiding the large energy consumption resulting from high temperature operation course. The fabricated silicon has a porous structure with average particle size of approximately 30 nm. The unique structure triggers pronounced electrochemical behavior for Li alloy/de-alloy reaction. The material delivers an initial discharge and charge capacity of 3844.7 mAh g⁻¹ and 3144.4 mAh g⁻¹ at the current density of 100 mA g⁻¹. With the current density increasing to 6 A g⁻¹ and 8 A g⁻¹, the material shows a reversible capacity of 860.1 mAh g⁻¹ and 413.4 mAh g⁻¹, respectively. The low material fabrication cost and satisfactory electrochemical performance make the low temperature aluminothermic reduction to be a promising route for silicon fabrication for next-generation lithium-ion battery. (paper)