Sol-gel synthesis and luminescence of undoped and Mn-doped zinc orthosilicate phosphor nanocomposites

Zn2SiO4 and Zn2SiO4:Mn particles embedded in SiO2 host matrix prepared by sol gel method under supercritical conditions of ethyl alcohol in two steps. Were prepared by a simple solid-phase reaction under natural atmosphere at 1200 °C after the incorporation of ZnO and ZnO:Mn nanoparticles, respectively, in silica monolith. In the case of SiO2/Zn2SiO4 nanocomposite, the powder with an average particle size of 80 nm shows a strong luminescence band centred at around 760 nm in the visible range. In addition, the PL spectrum for the SiO2/Zn2SiO4:Mn nanocomposite showed that a dominant peak at 525 nm appeared, which originated from the 4T1-6A1 transitions of Mn2+ ions. The luminescence properties of nanocomposites were characterized by emission and excitation spectra as well their dependencies of upon temperature and power excitation density.