Large-scale synthesis of ultrafine Si nanoparticles by ball milling

Si nanoparticles have been synthesized by ball-milling of graphite and SiO2 powders. The solid-phase reaction, C(graphite) + SiO2 --> Si + CO2, was fo und to be a novel technique for fabrication of ultrafine Si particles. The reduced Si in the powder assembled as nanoparticles with a wide range of di ameters. Multiple-peak structures were observed in the photoluminescence sp ectra of the Si nanoparticles at room temperature. The peak energies were f ound to coincide with the PL peak pinning energies previously reported in p orous Si. Thus, the fine structures of luminescence spectra could be attrib uted to the size quantization of the Si nanoparticles formed via solid-phas e reaction during ball-milling. (C) 2000 Elsevier Science B.V. All rights r eserved.