Component Dependence And Spectral Control Of Dy/Dy-CsPbI₃ Activated Fluorescent Glass

Dy³⁺is one of the most abundant rare earth elements.The emission intensity of its yellow and blue light is affected by the symmetry of the surrounding environment.Therefore,the relative strength of its emission intensity can be used as a symbol of the symmetry of the environment in which Dy³⁺is located in the glass structure and is widely used.Used as an optical probe for studying the structure and local symmetry of solid materials.Bismuth glass has the advantages of high transparency,low melting temperature,good thermal stability,and good glass forming properties.It is an excellent rare earth ion doped matrix material.However,the current forming mechanism of bismuth glass is still not very clear,and a unified conclusion has not been formed,and this has greatly hindered the application of bismuth glass.Therefore,Dy³⁺can be used as an optical probe to study the structure evolution and property changes of bismuth borosilicate glass,establish the relationship between the structure and properties of bismuth borosilicate glass,and conduct in-depth research on the structure and optical properties of bismuth borosilicate glass.In recent years,the semiconductor all-inorganic perovskite Cs Pb X₃QDs have attracted wide attention from researchers due to their unique optical properties.However,the poor thermal stability and humidity resistance of Cs Pb X₃ QDs greatly limit the application of perovskite quantum dots in LEDs.Therefore,it is necessary to embed quantum dots in inorganic glass to improve its thermal stability and chemical stability.Cs Pb I₃QDs lacks yellow light emitting elements,and its luminous quantum efficiency is lower than that of other quantum dots.This is the main problem that restricts the wide application of perovskite quantum dots in the field of lighting.Dy³⁺is an ideal material for adjusting the photoluminescence of quantum dots due to its unique spectral properties.Therefore,Dy³⁺can be doped into the Cs Pb X₃ perovskite quantum dot glass to provide the necessary yellow luminescence for the white light emission of the Cs Pb I₃ perovskite quantum dot glass,so as to realize the possibility of the application of all-inorganic perovskite C_SPb X₃QD_S solid-state luminescent material in optical devices WLED.The main research contents of this paper are as follows:1.The glass system composed of B₂O₃-（60-x）Bi₂O₃–40Si O₂–1Dy₂O₃（x=10,20,30,40）（mol%）was prepared by high temperature melting method.Using Dy³⁺ions as spectroscopic probes,the structural characteristics and optical properties of Dy³⁺-doped bismuth borosilicate（BBS）glass were studied from the aspects of infrared spectroscopy,Raman spectroscopy,light absorption,photoluminescence and lifetime.The results show that with the increase of B₂O₃ content,the network structure of bismuthate glass becomes denser,and the transition from[Bi O₃]tetrahedron to[Bi O₆]octahedron occurs in the glass system.When the B₂O₃content exceeds 30 mol%,the phenomenon of"boron abnormality"exists in BBS glass,[BO₄]tetrahedron begins to transform into[BO₃]triangle.In addition,according to the J-O theory,the J-O parameters,radiation transition probability,branch ratio and fluorescence lifetime of Dy³⁺in bismuth borosilicate glass are calculated.The increase of theΩ₂value and the Y/B ratio indicates that the disorder of the glass network has increased.The increase in fluorescence intensity,decay lifetime(τ_exp)and quantum efficiency（η%）proves that the enhancement of multi-phonon relaxation process of ⁴I_13/2,⁴G_11/2and ⁴I_15/2e level populating⁴F_9/2 level.On this basis,the relationship between the structural evolution of bismuth borosilicate glass and the change of optical properties is established,which helps to deepen the understanding of the structure of bismuth borosilicate glass and explore its potential applications in LED devices.2.Using the melting quenching method,successfully prepared Cs Pb I₃ perovskite quantum dot glasses doped with different concentrations of Dy³⁺ions.TEM results show that Dy³⁺doped Cs Pb I₃ QDs are grown in glass,and the average size of Cs Pb I₃ QDs decreases with the increase of Dy³⁺content,resulting in blue shift of absorption cutoff edge and emission spectrum.Element mapping proves that only a small part of Dy³⁺enters the perovskite quantum dot lattice,and most of Dy³⁺remains in the glass matrix.The rare earth ion Dy³⁺exchanges homogeneity during the formation of Cs Pb I₃ QDs:（1）When the Dy³⁺concentration is 0.1mo%,Dy³⁺creates defects,provides heterogeneous nucleation centers,and induces the formation of Cs Pb I₃ QDs.The luminous intensity of the dot increases.（2）When the Dy³⁺concentration continues to increase,too many defects produced by it inhibit the generation of Cs Pb I₃ QDs,which reduces the quantum efficiency of Cs Pb I₃ perovskite quantum dot glass.The test of thermal stability and moisture resistance proves that Dy³⁺doped Cs Pb I₃ perovskite quantum dot glass has excellent thermal stability and chemical stability.The Dy³⁺-doped Cs Pb I₃ QDs fluorescent glass film prepared by the spin coating method is assembled into a white light LED.By adjusting the concentration of Dy³⁺,the color adjustment from orange-red light to yellow-white light is realized,which proves that Dy³⁺doped Cs Pb I₃ calcium titanium Mineral quantum dot glass can realize the regulation of the luminescence performance of white light LED,which provides a new idea for realizing the wide application of Cs Pb I₃ QDs glass in the field of lighting.