Preparation And Properties Of Silicate Long Afterglow Phosphors

In this paper, the current situation, development, characteristic of phosphors, preparation and application prospect of phosphorescence system of silicate were summarized.In the paper, the long afterglow luminescent material of Sr₂MgSi₂O₇ was prepared by sintering at high temperature under the reductive atmosphere. The photoluminescence spectra were recorded on F-4500, XRD patterns of the samples were measured by the X-ray powder diffraction analytical instrument. The relationship between contents of Eu, Dy, B and luminescent properties have been studied, obtain a recipe used for good performance silicate phosphor. Factors influence luminescent properties, such as sintering temperature, sintering time, diameter of SiO2 power are investigated. A blue silicate long afterglow power is prepared by using solid reaction method. The initial luminance of the sample is 3000 mcd.m-2 and the decay time is 30 h. A phosphor of Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺ was synthesized by sol-gel method at the temperature lower than the tradition solid state reaction about 150℃. The phosphor synthesized by solid reaction exhibited a better afterglow character than the phosphor obtained by the sol-gel method, due to a higher trap concentration which was formed by a higher reaction temperature.In the paper, the synthesis and phosphorescent properties of the long lasting phosphorescent glass have been researched. samples were prepared with two methods.Glass 1G were prepared by the traditional ceramic synthesis method at 1300°C for 2h and in reductive atmosphere (one step method), Glass 2G was prepared by sintering the mixture of the powder of glass host and long lasting phosphorescent powder (two step method). Blue long lasting phosphorescent glass(2G) was prepared by sintering the phosphorescent powder of Sr2MgSi2O7:Eu²⁺,Dy³⁺ and glass host at the temperature of 1000℃¹100℃maintained for 8min¹2min under air atmosphere. The initial luminance of the 2G is 400 mcd.m-2 and the decay time is 2 h.