Luminescent Silicon Nanocrystal embedded Sodium Silicate Glass

Abstract

Green luminescent silicon nanoparticles (Si NPs), embedded in sodium silicate (SS) based glass, have been prepared by a simple green chemical synthesis route. (3-aminopropyl) triethoxysilane (APTES) was reduced by sodium ascorbate (SA) in a one-step synthesis method to prepare Si NPs. Extending the same route SS based glass was synthesised by slow evaporation of the aqueous solution of colloidal Si NPs at room temperature. Colloids of Si NPs and the SS-based glass exhibit intense room temperature greenish photoluminescence (PL) that can be detected with the naked eye. Structural investigations reveal that the Si NP sample contains dominant amorphous phase with trace amount of Si nanocrystals (NCs). Analysis of optical properties of the Si NP sample indicates that green PL is dominantly due to the contribution of oxide enriched surface states rather than quantum confinement of excitons and likewise the PL from the SS based glass is due to the presence of trace amount of Si NCs along with agglomerated amorphous oxide embedded in the glass. There is a clear indication of selective reflectance from the prepared SS based glass.