The Study Of The Influence Of Boron To The Luminescent Material Doped With Eu Or Tb

Eu-B-doped and Tb-B-doped SiO₂ luminescent material was prepared by Sol-Gel process, and we studied the influence of the Boron ions to Eu³⁺ and Tb³⁺ ions by altering the content of the Boron ions in the system. The microstructure was studied with DTA-TG, IR spectrum, and XRD. Then the luminescence property and the influence of the Boron ions to the material were studied with fluorescence excitation spectrum and emission spectrum. The DTA-TG analysis and the XRD analysis shows: most water and organic substance in the Eu-B-doped and Tb-B-doped SiO₂ luminescent material removed under 120℃, and the volatile matter in the gel removed completely under 500℃.The sample annealed at 800℃is in amorphous state, and the Eu³⁺ ion and Tb³⁺ ion did not form other phase and exist with ion form inner doping content.The IR spectrum result indicated that following the increase of the content of the boron, it enter the Si—O network structure of the sample annealed at 800℃, and breached the symmetry of network, and there formed Si-O-B bonds in luminescent materials.The fluorescence excitation spectrum and emission spectrum of Eu-B-doped SiO₂ luminescent material shows: when monitoring wavelength is 612nm, the fluorescence excitation spectrum is obtained. And the exicitation spectrum shows many excitation peaks,which are O2--Eu³⁺ electronic transition and 7F0-5F4,7F0-5L3,7F0-5D4,7F0-5L7,7F0-5L6,7F0-5D3,7F0-5D2 transition for Eu³⁺ respectively, and in these transition 7F0-5L6 transition at 395nm is strongest. Whe the material simulated under the 7F0-5L6 transition of Eu³⁺, the 5D0→7FJ(J=0,1,2,3,4)electron transition discovered. When the boron ions are introduced to the material ,the luminescence intensity increased obviously. It may be the energy absorbed by the boron transferred to Eu³⁺.When Si : B less than58 :1, the luminescent material intensity did not vary clear, and when Si : B is equal to 9 : 1, the intensity increased obviously and there is a 2nm blue shift in fluorescence emission spectrum. Within 200℃～800℃, with the increasing of temperature, the luminescence intensity increased. But, when the temperature increased to 850℃, the luminescence intensity decreased. The annealing temperature mainly influenced the luminescence intensity of Eu³⁺ and has little effect on the station of the peak.The fluorescence excitation spectrum and emission spectrum of Tb-B-doped SiO₂ luminescent material shows: when monitoring wavelength is 543nm, the fluorescence excitation spectrum is obtained. And the exicitation spectrum shows many excitation peaks,which are 4f8-4f75d1 transition(7F-7D), 4f8-4f75d1 transition(7F-9D,â–³S=1)and 7F6-5D2 ,7F6-5L10 ,7F6-5D3 , 7F6-5D4 transition for Tb³⁺ respectively.The material simulated under the 4f8-4f75d1 transition(7F-7D)of Tb³⁺,photo source had the D4-7F5,5D4-7F4 and 5D4-7F3 electron transition. When the boron ions are introduced to the material ,the luminescence intensity increased obviously. It may be the energy absorbed by the boron transferred to Tb³⁺. when Si:B is equal to 39:1, the ⁵D₄-⁷F₅SiO2 transition of Tb³⁺ion varied to 550.2nm,had 7nm red shift, and only find ⁵D₄-⁷F₅ transition in the fluorescence emission pectrum. The material has good monochromaticity and a great valuable to be use. Within 200℃～800℃,with the increasing of temperature, the luminescence intensity increased. Especially within600℃～800℃, the increase of luminescence intensity is very clear. the But, when the temperature increased to 850℃, the luminescence intensity decreased.