Study On Preparation,luminescent Properties And Optical Thermometry Of Rare-earth Doped Phosphate Glass And Nano Glass-ceramics

Rare earth doped luminescent materials were widely used in many fields such as optical communications,solar cells,white LED,optical thermometry and fluorescent display in daily production and life,phototherapy,fluorescent biomarker and bioimaging in biomedical technology,laser weapons,3D imaging and energy storage in military affairs and national defence due to their excellent optical properties.Therefore,the rare earth doped luminescent materials have attracted extensive attention of researchers all over the world.Owing to the simple preparation,high transparency and excellent luminescent properties,rare-earth luminescent glass and glass-ceramics have great application foreground.Therefore,the research based on the rare earth doped luminescent glass and glass-ceramics have important theoretical significance and application value.In this paper,the Na-Ca-P-B-Zr,Na-Zn-P-B and K-Zn-P-B systems phosphate glasses have been successfully prepared by melt-quenching method,and a series of phosphate nanocrystalline glass-ceramics were prepared by subsequent controlled crystallization.The structure and thermal stability of glasses and glass-ceramics were investigated by XRD,TEM,FT-IR,DSC and so on.The luminescent properties and energy transfer mechanism of glasses and glass-ceramics were studied by transmission spectra,up and down excitation and emission spectra,fluorescence decay spectra,Inokuti-Hirayama model,chromaticity coordinates and color correlate temperature calculations.Furthermore,the optical thermometry property of Na-Zn-P-B and K-Zn-P-B glasses and glass-ceramics based on the fluorescence intensity ratio?FIR?technique were investigated.The main experimental results are as follows:1.Glass structure analysis confirmed that all glasses samples exhibited short-range ordered long-range disordered amorphous structure,and the network structure of glasses were mainly composed of three network groups[PO₄],[BO₄]and[BO₃],and they were constituted a disordered network structure.The thermal analysis results showed that all glasses had good thermal stability.But,when rare-earth doping into glasses matrix,the crystallization activation energy of glasses increased,which indicated that rare-earth doping inhibited the crystallization of glass.2.Under the excitation at 362 nm,the 1.0 Tm³⁺/2.0 Tb³⁺/1.0 Eu³⁺?mol%?tri-doped Na-Ca-P-B-Zr phosphate glasses could achieve white light emission,with the chromaticity coordinates of?0.3418,0.3272? and the color correlate temperature of 5055.95 K;Under the excitation at 354 nm,the 0.4 Tm³⁺/0.6 Dy³⁺?mol%?co-doped Na-Zn-P-B phosphate glasses could also achieve white light emission,and the chromaticity coordinates of?0.3471,0.3374? and the color correlate temperature of 4866.21 K.Those results were very close to the chromaticity coordinates of standard white-light illumination?0.3333,0.3333? and the color correlate temperature of 5454.12 K.Therefore,the prepared luminescent glass materials had broad potential applications in many fields such as solid-state lighting and plane display and so on.3.After analyzing fluorescence decay spectra through Inokuti-Hirayama model theory,it came to a conclusion that the energy transfer in the Na-Zn-P-B system phosphate glass of Dy³⁺?Tm³⁺ was the non-radiative transition of electric quadrupole-electric quadrupole interaction and Tb³⁺?Eu³⁺ was the non-radiative transition electric dipole-electric dipole interaction.4.Under the near-ultraviolet excitation at 378 nm in the temperature range of 303-753 K,the Tb³⁺/Eu³⁺ co-doped Na-Zn-P-B system glasses with the absolute sensitivity was 1.00×10^-2 K^-1 and the maximum relative sensitivity was 1.17% K^-1.The Yb³⁺/Er³⁺co-doped Na-Zn-P-B system glass had a maximum absolute sensitivity of 4.94×10^-3K^-1and the maximum relative sensitivity was 1.22% K^-1 in the temperature range of 303-753 K and under the excitation of 980 nm.The Yb³⁺/Er³⁺co-doped K-Zn-P-B system glasses had a maximum absolute sensitivity of 7.46×10^-3K^-1 and the maximum relative sensitivity was1.43% K^-1 in the temperature range of 298-748 K.The absolute sensitivity of Yb³⁺/Tb³⁺/Ho³⁺three-doped K-Zn-P-B system glass at 980 nm excitation was 3.10×10^-3K^-1 in the temperature range of 298-598 K,and the maximum relative sensitivity was0.21% K^-1.5.Under the excitation of 980 nm,the Yb³⁺/Er³⁺ co-doped Na-Zn-P-B system glass-ceramics with the maximum absolute sensitivity was 5.73×10^-3K^-1 and the maximum relative sensitivity was 1.33% K^-1 in the temperature range of 303-753 K.The maximum absolute sensitivity of Yb³⁺/Er³⁺ co-doped K-Zn-P-B system glass-ceramics in the temperature range of 298-798 K was 4.59×10^-3K^-1,and the maximum relative sensitivity was 1.67% K^-1.Yb³⁺/Tb³⁺/Ho³⁺tri-doped K-Zn-P-B system glass-ceramics with the absolute sensitivity of 5.40×10^-3 K^-1 and the maximum relative sensitivity was 0.18% K^-1 in the temperature range of 298-648 K.