Study On Preparation And Properties Of Inorganic Rare Earth Oxysalts Luminescent Materials

A series of inorganic borates and phosphates luminescent materials actived by rare earth ions and self-actived tungstate luminescence materials have been prepared and the main research contents as follows:1.Single crystal K₃Gd₃B₄O₁₂ has been synthesized by high temperature molten salt method and its crystal structure was determined by single-crystal X-Ray diffraction analysis.K₃Gd₃B₄O₁₂2 possessed the cubic crystal system and P2/c space group.A series of phosphors based on borates including orange phosphor K₃Gd_3-xSm_xB₄O₁₂?x=0⁰.2?,green phosphor K₃Gd_3-x-x B₄O₁₂:xTb³⁺?x=0⁰.8?,red phosphor K₃Gd_3-yB₄O₁₂:yEu³⁺?y=0⁰.4?,yellow phosphor PbGd_1-xB₇O₁₃:xDy³⁺?x=0⁰.14?,multi-colored phosphor K₃Gd_2.2-y.2-y B₄O₁₂:0.8Tb³⁺,yEu³⁺?y=0⁰.4?and K₃Tb_1-xEu_xB₆O₁₂?x=0¹?have been prepared using high temperature solid state reaction method.Their luminescence properties were investigated,respectively.Under 405 nm light excitation,K₃Gd_3-xSm_xB₄O₁₂ phosphor could emit orange light and the optimum doping concentration of Sm³⁺was 0.01.K₃Gd_3-xB₄O₁₂:xTb³⁺phosphor could emit green light,the optimum doping concentration of Tb³⁺was 0.8 and Gd³⁺was able to transfer charge to Tb³⁺,under the 275 nm light excitation.K₃Gd_3-yB₄O₁₂:yEu³⁺phosphor could emit intense red light when excited by 400 nm light.And there was charge transfer between Gd³⁺and Eu³⁺.With the increase of Eu³⁺doping concentration,the colour of K₃Gd_2.2-yB₄O₁₂:0.8Tb³⁺,yEu³⁺phosphor could change from green to yellow,orange and red successively when excited by the light with wavelength of 377 nm because a seris of charge transfers occurred including Gd³⁺?Tb³⁺,Gd³⁺?Eu³⁺and Tb³⁺?Eu³⁺.Similarly,with the rising of Eu³⁺doping concentration,K₃Tb_1-xEu_x B₆O₁₂ phosphor could emit green,yellow,orange and red light in sequence when excited by the light with wavelength of 377 nm due to the charge transfer of Tb³⁺?Eu³⁺.Under the 275 nm and 348 nm light excitation,PbGd_1-xB₇O₁₃:xDy³⁺phosphor could emit yellow light.The optimum doping concentration of Dy³⁺was 0.08 and Gd³⁺could transfer charge to Dy³⁺.Besides,the lifetime of PbGd_1-xB₇O₁₃:xDy³⁺phosphor was 0.495 ms.2.Single crystal Na₁₃Sr₂Ta₂?PO₄?₉ and Li₂Na₂P₂O₇ were synthesized using high temperature molten salt method and theircrystal structure were determined by single-crystal X-Ray diffraction analysis.Na₁₃Sr₂Ta₂?PO₄?₉ belonged hexagonal crystal system and P6₃/m space group.Li₂Na₂P₂O₇ possessed hexagonal crystal system and P6₅22 space group.A series of phosphors based on phosphates containing orange phosphor KBa₂?PO₃?₅:xSm³⁺?x=0⁰.06?and KPb_4-x?PO₄?₃:xSm³⁺?x=0⁰.5?,blue phosphor KBa_2-xTm_x?PO₃?₅?x=0⁰.1?,green phosphor KPb_4-x?PO₄?₃:xTb³⁺?x=0⁰.22?,white phosphor Na₁₃Sr_2-xDy_xTa₂?PO₄?₉?x=0⁰.14?and red phosphor Li₂Na₂P₂O₇:0.01Eu³⁺were prepared by high temperature solid state reaction method and their photoluminescence properties were investigated,respectively.Under the 400 nm light excitation,KBa₂?PO₃?₅:xSm³⁺phosphor could emit orange light and the optimum doping Sm³⁺concentration was 0.01.KBa_2-xTm_x?PO₃?₅ phosphor emitted intense blue light under the excitation of 351 nm light and the optimum doping concentration of Tm³⁺was 0.04.KPb_4-x?PO₄?₃:xSm³⁺phosphor also could emit orange light when excited by 404 nm light and 0.01 was the optimum doping concentration.Under the 377 nm light excitation,KPb_4-x?PO₄?₃:xTb³⁺phosphor could emit green light and the optimum doping concentration of Tb³⁺was 0.04.Besides,Na₁₃Sr_2-xDy_xTa₂?PO₄?₉ phosphor was able to emit white light under the excitation of 350 nm light.And the optimum doping concentration of Dy³⁺was 0.1.Li₂Na₂P₂O₇:0.01Eu³⁺phosphor emitted red light when excited by 394 nm light.3.Single crystal CsGa_0.333W_1.667O₆ was prepared by high temperature molten salt method and its crystal structure was determined by single-crystal X-Ray diffraction analysis.CsGa_0.333W_1.667O₆ belonged cubic crystal system and Fd3m space group.And it featured a typical pyrochlore structure.Self-actived CsGa_0.333W_1.667O₆ luminescence material was synthesized using high temperature solid state reaction method and its photoluminescence properties were investigated in detail.Under the 323 nm light excitation,CsGa_0.333W_1.667O₆could emit intense blue light.