Preparation And Luminescence Properties Of Rare Earth Doped Yttrium Aluminate

Yttrium aluminate is widely used in the preparation of phosphors because of its excellent chemical stability,thermal stability and excellent optical properties.Therefore,yttrium aluminate phosphors have broad application value in the field of lighting display.In this paper,Ba₂YAl O₅(BYAO)is selected as the phosphor matrix material and doped with rare earth ions to study the material synthesis and preparation process,morphology,luminescence characteristics,thermal stability,color purity and color temperature.1.BYAO:x Eu³⁺red phosphors were prepared.The crystal structure and luminescence characteristics are studied.The excitation spectrum consists of the charge transfer band between O^2-?Eu³⁺and the characteristic excitation peak of Eu³⁺.The strongest peak of the emission spectrum of BYAO:x Eu³⁺phosphor is at 614 nm,the optimal doping concentration of Eu³⁺is 0.2,the critical distance is 11.16(?),and the concentration quenching is caused by the interaction between the nearest neighbor ions.BYAO:0.2Eu³⁺phosphor show obvious heat quenching characteristics.By changing the concentration of Eu³⁺,the CIE chromaticness coordinates will be distributed in different color regions.BYAO:x Eu³⁺belongs to the color adjustable phosphors.BYAO:0.2Eu³⁺phosphor has a high color purity of 96.4%.2.BYAO:0.2Eu³⁺,x Na⁺phosphors were prepared.The effects of charge compensation agent Na⁺at different concentrations on crystal structure and luminescence characteristics were studied.The strongest excitation and emission peak of phosphors were 465 nm and 613 nm,respectively.The optimal doping concentration of Na⁺was 0.03,and the emission peak of BYAO:0.2Eu³⁺,0.03Na⁺was higher than that of BAYO:0.2Eu³⁺.BAYO:0.2Eu³⁺,0.03Na⁺thermal quenching activation energy0.058 e V,color coordinate is located at(0.61,0.39),very close to the standard color coordinate stipulated by the International Commission on Lighting.3.BAYO:x Sm³⁺phosphors were prepared and their photoluminescence was studied.The luminescence of BYAO:x Sm³⁺phosphors came from the transition of 4F shell of Sm³⁺,the excitation spectrum was located at 404 nm with the strongest excitation,and the emission spectrum was located at 567 nm with the strongest emission.The optimal doping concentration of Sm³⁺is 0.04,the effect between the nearest neighbor ions led to the phenomenon of concentration quenching.The thermal stability of BAYO:0.04Sm³⁺phosphors is relatively stable at high temperatures.4.BAYO:0.04Sm³⁺,y Eu³⁺phosphors were prepared.With the increase of Eu³⁺doping concentration,the diffraction angle shifted to the left at a small angle,and the peak strength of characteristic emission peak of Sm³⁺at 567 nm gradually decreased,while that of characteristic emission peak of Eu³⁺at 613 nm first increased and then weakened.The energy transfer between Sm³⁺and Eu³⁺was caused by the interaction between the nearest-neighbor ions.The average decay time of BAYO:0.04Sm³⁺,y Eu³⁺phosphors gradually decrease as the concentration of doped Eu³⁺increases,and they all have a lower color temperature.