Silicatc phosphors doped with Eu2+ find application in solid state lighting, plasma display panel, liquid crystal display and long after glow. In present work long lasting silicate phosphors are prepared by a modified combustion synthesis. The photoluminescence spectra and long lasting decay curves are measured. The Emission wavelength of Ba2MgSi2O7: Eu2+ is observed at 500 nm for excitation 345 nm, The emission wavelength of Ba2ZnSi2O7: Eu2+ is obtained at 496 nm at excitation 350 rim, Decay constants are calculated for both the phosphors.

Metasilicates are important class of materials. They find applications in many diverse areas. Silicates are widely used as adsorbents, sensors, in production of ceramics, as bioactive materials, as microwave dielectric etc. A large number of phosphors based on metasilicate hosts are known. The conventional routes for synthesis of silicates are the solid state reaction and sol-gel. The synthesis temperature for metasilicates is usually in excess of 1100 degrees C. Here, we report for the first time the wet-chemical preparation of alkaline earth metasilicates. Though the as-prepared compounds were poorly crystallized, annealing at 700 degrees C was sufficient for the formation of well defined crystalline phases. Photoluminescence was also observed in these compounds after activating with suitable dopants. (C) 2011 Elsevier B.V. All rights reserved.

Sr3MgSi2O8:Eu2+ and Sr2MgSi2O7:Eu2+ phosphors find uses in applications such as plasma display panel (PDP), solid-state lighting, longafter glow. Preparation of these phosphors by a modified combustion synthesis is described in this paper. As-prepared samples did not show photoluminescence. After reducing the samples at 900°C, characteristic Eu2+ emission was observed. Preparation of these phosphors by using similar methods helped clarifying various results obtained for Sr3MgSi2O8:Eu2+ by different investigators.