Improved Low Temperature Solution Synthesis of Silicon Nanoparticles for Lithium-Ion Batteries

Silicon nanoparticles have extraordinary electrochemical performance for lithium-ion batteries. This paper gives an improved low temperature solution synthesis route of Si NPs. Reduced by magnesium and then passivated by four kinds of amines/amides respectively, stable yellow Si NPs ranging from 5-50 nm were prepared. When passivated by N-methyl-2-pyrrolidone, grape-like aggregation of 5-20 nm particles were generated. FTIR, XRD, SEM and Electrochemical Characterization were performed to confirm the product. The Si NPs passivated by NMP achieve good electrochemical performance with a first discharge capacity of 1154 mAhg-1 at a current density of 200 mAg-1 and good capacity retention of 95.3% after 5 cycles.