Synthesis And Luminescent Properties Of Eu,M(M= Ce,Tb,Mn,Er) Activated Silicates Glasses And Glass-ceramics

The rare-earth and transition metal ions doped in glasses and glass-ceramics have attracted more eyes due to their excellent properties,chemical stability,mechanical strength and so on.In this thesis,Eu,M?M=Ce,Tb,Mn,Er?single doped/co-doped in Mg O-Ga₂O₃/Al₂O₃-SiO₂ system glasses and glass-ceramics were prepared by sol-gel method.The influence of heat treatment atmosphere,temperature,doped ions and concentration,matrix composition to the luminescent properties of glasses and glass-ceramics were researched.The main research results of this thesis as follows:?1?Eu/Ce doped MgO-Ga₂O₃-SiO₂ system glasses and glass-ceramics system were prepared.It is found that being heated in air is easier to form nano-crystalline than in reductive atmosphere due to the difference of oxygen pressure.As the temperature increased,the MgGa₂O₄ nano-crystalline are formed and grow up.When heated in air,the 5D₀?⁷F_J emission transition of Eu²⁺are observed.Ce⁴⁺are unluminescent due to the lack of 4f-electrical layer.When Eu/Ce co-doped samples,the energy transfer from Eu³⁺?Ce⁴⁺appears.When heated in reductive atmosphere,the characteristic emission of Eu²⁺and Ce³⁺are observed.When co-doped samples,the energy transfer from Ce²⁺to Eu²⁺can be observed.Meanwhile,the heated temperature and matrix composition also have influence on the formation,size and amount of nano-crystalline,and then influence the luminescent properties.?2?5MgO-5Al₂O₃-90Si O₂:Ce/Tb/Eu glasses are prepared through so-gel method.When single doped samples were heated in reductive atmosphere,the characteristic emissions of Ce³⁺,Tb³⁺and Eu²⁺can be observed.The emission peaks of Ce³⁺and Eu²⁺can be affected by the crystal field strength and have purple and blue emission at 410nm and 440 nm,respectively.Tb³⁺have the green emission at 550 nm.When co-doped,the energy transfer of Ce³⁺?Eu²⁺and Ce³⁺?Tb³⁺are observed.As the heated temperature increased,the SiO₂ nano-crystalline will grow up and homodisperse,so the luminescent efficiency can be improved.?3?The synthesis and luminescent properties of rere-earth Eu,Er and transition metal Mn doped MgO-Ga₂O₃-SiO₂ system glasses and glass-ceramics are researched.The formation of MgGa₂O₄ nano-crystalline in matrix has some influence on the luminescence intensity and efficiency.Mn²⁺has broad emission at 511 nm come from the ⁴T₁?⁶A₁ green emission and 634 nm with red emission.when Eu/Mn co-doped samples,the energy transfer of Mn²⁺?Eu²⁺appears,and the energy transfer efficiency will decrease with the increase of Mn concentration.The composition of MgO-Ga₂O₃have different influence on Eu/Mn single doped and co-dope samples.The up-conversion and mechanism of Er doped samples,the influence of heat treatment temperature and matrix composition are also studied.