Colour Tunable And Energy Transfer Of KAlSiO₄:Re³⁺（Re=Dy,Sm,Eu,Tb） Phosphor

This paper mainly studies the photoluminescence properties of new yellow,red and green aluminosilicate luminescent materials doped with rare earth ions Dy³⁺,Sm³⁺,Tb³⁺,Eu³⁺.The main synthesis method used is the high temperature solid phase method,and the main matrix selected is potassium aluminosilicate（KAlSiO₄）.Analyze and determine the luminescence performance of the synthesized sample through the energy transfer between ions and the color control characteristics caused by the energy transfer.In the later experiments.The specific analysis and research content are as follows:（1）This study presents the photoluminescence characteristic analysis of red phosphors of KAlSiO₄:1.5 mol%Sm³⁺,x mol%Eu³⁺,prepared via high-temperature solid-phase reaction.The results show that the X-ray diffraction（XRD）refinement results are reliable.A maximum energy transfer efficiency of 97.8%was achieved.The color purity of the phosphor was as high as 92.97%,and the internal quantum yield gradually changed from 32%to 51%.Ultimately,these results confirm that the silicate phosphor is suitable for the red component in the three primary color phosphors of white light-emitting diodes.（2）A series of Dy³⁺,Sm³⁺co-doped KAlSiO₄ phosphor materials were prepared by high temperature solid phase method.When the characteristic excitation wavelength of Dy³⁺is used to excite KAlSiO₄:1mol%Dy³⁺,wmol%Sm³⁺,there is a resonant non-radiative energy transfer from Dy³⁺to Sm³⁺in the emission spectrum,with a red shift at 528nm;it is judged that the energy transfer efficiency from Dy³⁺to Sm³⁺can reach up to 52%.The internal quantum efficiency under 386nm excitation gradually increased from 25.8%to 42.6%.（3）KAlSiO₄:1.5 mol%Tb³⁺,xmol%Li⁺was prepared via a high-temperature solid-phase method.The results show that the Li⁺doping shifts the strongest diffraction peak to a high angle direction,reducing grain size by 11.4%.At a Li⁺concentration of 1.5 mol%,the sample has strong absorption in the ultraviolet light range from 250–400 nm.The colour purity of the sample and the internal quantum yield increase to 83.3%and 42%,respectively.The emission intensity at200°C is 95.1%of its value at room temperature,indicating that the phosphor has excellent thermal stability when x=1.5.These results show the feasibility of using the silicate phosphor for generating the green light component of white light-emitting diodes（WLEDs）for solid-state lighting.