Study On The Luminescence Properties Of Dysprosium And Europium Doped Glass For White LED

Solid state lighting has always been considered as the most ideal form of lighting.At present,commercial solid state lighting is mainly realized by Galn N blue chip combined with YAG:Ce yellow light phosphor.Although this combination has many advantages,there are still many shortcomings.For example,the combination of white light is lack of red component and poor color performance.This combination of transparent resin encapsulation will cause uneven distribution of phosphor.Poor heat dissipation performance leads to rapid aging of the resin,yellowing of light,and discoloration,affecting the service life.Luminescent glass can be used as a candidate material for the study of white LED and is of great research value,due to its excellent stability,high transparency,simple preparation process and the ability to produce various shapes.In this paper,four series of Dy³⁺/Eu³⁺doped germanium silicon barium gallium luminescence glass（hereinafter referred to as GSBG glass）were prepared by traditional high temperature melt cooling method.By X-ray diffraction（XRD）,Fourier infrared spectroscopy,Raman spectroscopy,the structure of glass are analyzed.The luminescence properties of glass are studied through the absorption and transmission spectra,excitation and emission spectrum,and fluorescence decay time.A series of basic performance parameters（density,refractive index,band gap,color coordinate,color temperature,color purity,etc.）of the glass were measured and calculated.The energy transfer form of doped rare earth was studied in combination with the luminescence theory of rare earth（J-O theory）and the energy transfer theory（Dexter’s energy transfer formula and I-H model）.A variety of[SiO₄],[GeO₄],[GeO₆]and[SiO₄]&[GeO₄]ligands were found in the GSBG glass system.The change of Ge/Si ratio would cause the change of these structures and affect the spacing of the doped rare earth ions,the structural symmetry of the environment in which the rare earth ions are located,and the luminescence intensity of the glass.These structures were analyzed by infrared Raman and confirmed by theory,and the optimal Ge/Si ratio was found.In the study of the luminescence properties of Dy³⁺/Eu³⁺doped GSBG glass,it is found that Dy³⁺ions mainly present blue light（483 nm）and yellow light（574 nm）,and white light emission can be obtained when doped alone,while Eu³⁺ions show red light at 589 nm and 614 nm,and the highest color purity reaches 96.6%.There is an energy transfer from Dy³⁺to Eu³⁺,and the addition of Eu³⁺can regulate the white light of Dy³⁺,which effectively solves the problem of lack of red light in Dy³⁺single-doped white light glass.This paper has a certain reference value for the study of the light emitting glass materials doped with rare earth ions for white LED.The theoretical and experimental analysis used in this paper has a certain guiding significance for the study of the luminescence of rare earth ions and the glass structure.