A solid state synthesis for obtaining nanocrystalline silicon was performed by high temperature reduction of commercial amorphous nanosilica with magnesium powder. The obtained silicon powder contains crystalline silicon phase with lattice spacings characteristic of diamond cubic structure (according to high resolution TEM), and an amorphous phase. In 29Si CP MAS NMR a broad multicomponent peak corresponding to silicon is located at −61.28 to −69.45ppm, i.e. between the peaks characteristic of amorphous and crystalline Si. The powder has displayed red luminescence while excited under UV illumination, due to quantum confinement within the nanocrystals. The silicon nanopowder was successfully dispersed in water containing poly(vinyl alcohol) as a stabilizing agent. The obtained dispersion was also characterized by red photoluminescence with a band maximum at 710nm, thus enabling future functional coating applications.
Accession Number: S0022459610001702; Author: Kravitz, Keren (a); Author: Kamyshny, Alexander (a, ⁎); Author: Gedanken, Aharon (b); Author: Magdassi, Shlomo (a); Affiliation: Casali Institute of Applied Chemistry, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel; Affiliation: Department of Chemistry and Kanbar Laboratory for Nanomaterials, Bar-Ilan University Center for Advanced Materials and Nanotechnology, Bar-Ilan University, Ramat-Gan 52900, Israel; Number of Pages: 6; Language: English;