摘 要:按2(Sr0.99,Eu^2+0.01)O-0.16B2O3-0.84P2O5配料以固相法合成藍色熒光粉。該熒光粉在還原性氣氛中,分別在1100,1150,1200℃和1250℃下進行焙燒。對不同溫度下制成的樣品進行X射線衍射分析,確定樣品的晶體結構及晶相組成。通過測定樣品的激發光譜和發射光譜,研究了焙燒溫度對熒光粉結構的影響。結果表明:在1200℃下合成的熒光粉Sr6BP5O20為單一相,屬四方晶系,P4/mmm空間群,晶胞參數分別為α=0.9794nm;c=0.9516nm,對應發射譜中478nm的發射峰;在低于1200℃下合成的熒光粉中含有α-Sr3(PO4)2和α-Sr2P2O72個晶相,對應發射譜中420nm的發射峰。
關鍵詞:硼磷酸鹽;藍色熒光粉;光致發光;
Abstract:Blue phosphors with the formula of 2(Sr0.99. Eu^2+ 0.01)O-0.16B2O3-0.84P2O5 were synthesized by a solid state reaction method. Phosphors were calcined at 1 100, 1 150, 1200℃ and 1250 ℃ under a reducing atmosphere. Photoluminescence spectra of these phosphors were measured. The effects of calcining temperature on structural variations of the phosphors were investigated. According to X-ray diffraction results, the crystal assembly of the sample calcined at 1200℃ is Sr6BP5O20 with a unitary tetragonal phase in the P4/mmm space group with the cell parameters a and c as 0.979 4 nm and 0.951 6 nm, corresponding to the emission at 478 nm. In the case of phosphors synthesized at temperatures lower than 1200℃, α-Sr3(PO4)2 and α-Sr2P2O7 phases were found with the emission at 420 nm.
Key words:borophosphate; blue phosphors; fluorescence spectra
As the most promising candidate to replace conventional fluorescent lamps,light.emi Ring diodes(LEDs) have been in dem and for solid.state lighting technology in recent years.L _o Although the simulated high.color.
rendering potential of light sources consisting Of 36I)_一400 nln ultraviolet LED (Uv.LED)and tricolor phos.phors has been reported an d experimentally confirmed,Lthere are currently insufficient references on the use of phosphor converted to UV LED as illumination sources.
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