Study On Luminescence Properties Of Rare Earth Doped Phosphate Glass-ceramics

The rare earth phosphor is the light conversion material used in the widely used fluorescent lamp and color picture tube.It can also be made up and supplemented in the LED lighting.It has a strong practical value and economic value for its research.Rare earth phosphate glasses and glass ceramics are studied in this paper.The basic theory of luminescence of rare earth phosphor is introduced.The basic theory of luminescence of rare earth phosphor is verified by experiment.The luminescence intensity of rare earth is improved by using glass ceramics.A kind of single matrix white phosphor powder has been prepared and the ideal white light has been obtained.The luminescence intensity of white light is improved by using glass ceramics.1.Phosphate glasses doped with Eu³⁺,Tb³⁺and Tm³⁺were prepared by melt annealing.Their emission spectra excited by 365nm violet line were measured.According to the energy level diagram of rare earth ions,the energy level transitions corresponding to the emission peak wavelengths are analyzed.It is confirmed that the emission spectra of rare earth ions RE³⁺are linear,and the f-f transition of electrons is allowed.The wavelength of the emission peak is determined by the energy level of the rare earth ions,which is not affected by the matrix,and is in good agreement with the J-O theory of the rare earth ion luminescence.2.The glass ceramics with single Tm³⁺doping were treated.First,the heat treatment temperature was determined by differential thermal analysis,and then the glass samples were subjected to additional heat treatment for 5,10 and 20 hours.The formation of glass ceramics was confirmed by X-ray diffraction and transmission electron microscopy.In the end,the luminescence intensity of rare earth ions can be significantly enhanced by the emission spectra of 365nm excitation.In the experiment,the heat treatment increased more than 2 times after 5 hours,and the heat treatment increased more than 4 times for 20 hours,and the enhancement multiplier increased with the increase of heat treatment time in the experiment.3.A white light phosphor with a single matrix was prepared.Three rare earth ions of Eu³⁺,Tb³⁺and Tm³⁺were prepared by experiment,and the doping concentration of Eu³⁺was changed.The glass samples were formed by extra heat treatment for the glass samples for 5 hours.The emission spectra of several samples under 365nm were compared,and the spectra were explained.It is found that the co doping of Eu³⁺,Tb³⁺and Tm³⁺ions can directly emit white light,and the luminescence intensity of the rare earth ions will not affect each other basically,only the concentration of each doped can be determined,and the doping concentration of some rare earth ions can change the luminescence intensity of the rare earth ion and adjust the white light CIE coordinates.The glass ceramics can also significantly increase the intensity of white light,but also make the CIE coordinates of white light change slightly.