Preparation And Properties Of Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺ Long Afterglow Phosphor And Its Application In The Glaze

Silicate long afterglow phosphor has excellent chemical stability,heat stability and water resistance,and it has wide potential applications in many areas including security signs,traffic signs,and self-luminous crafts.However,its long-lasting phosphorescence property was inferior to that of aluminates materials.In order to improve the performance of Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺long afterglow phosphor,experiments have been carried out with different preparation process and different ion doping.What's more,the process parameters of microwave synthesis of fluorescent glaze were also discussed.The Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺phosphor was synthesized by high temperature solid-state method and chemical precipitation method.The process parameters of these two process methods were compared and analyzed.The samples were characterized by X-ray diffraction?XRD?,scanning electron microscope?SEM?,photoluminescence?PL?,thermoluminescence?TL?and decay curves.The mechanism of the Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺long afterglow phosphor was discussed.It concluded that high temperature solid-state method was a better preparation process method than chemical precipitation method.The Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺,R⁺?R⁺=Li⁺,Ag⁺?phosphor was synthesized by high temperature solid-state method.The influence of the two kinds of monovalent ions,Li⁺or Ag⁺,on the crystal structure and luminescence properties of the Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺phosphor was discussed.The optimum process parameters of Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺,Li⁺phosphor was choosed by orthogonal experiment.The results are as follows,sintering temperature is 1250?,n(Eu²⁺)is 1.5 mol%,n?B?is20 mol%,n?Li⁺?is 2.5 mol%.The application of Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺phosphor in the fluorescent glaze was studied.The optimum process parameters for the synthesis of lower temperature fluorescent glaze and higher temperature fluorescent glaze were studied by microwave method.The results shows that the higher the sintering temperature,or the longer the microwave holding time,the more serious is the damage of the Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺phosphor by high temperature melting,the more Eu²⁺is oxidized to Eu³⁺,and the worse the luminescent performance of the luminescent ceramic glaze.The optimum process parameters for microwave synthesis of lower temperature fluorescent glaze are:microwave sintering temperature is 900?,microwave holding time is 3 min,luminous powder content is 30 wt%to 40 wt%;and the optimum process parameters for microwave synthesis of higher temperature fluorescent glaze are:microwave sintering temperature is 1100?,microwave holding time is 1 min,luminous powder content is 40 wt%to 50 wt%.