温度和敏化剂对CaSO_4∶Eu,Ce的光谱性质的影响  

Effect of Temperature and Sensitizer on Luminescent Properties of CaSO_4:Eu^(2+),Ce^(3+)

作　　者：余锡宾[1] 熊娟[1] 丁云峰[1] 王则民[1] 

机构地区：[1]上海师范大学化学系,上海200234

出　　处：《中国稀土学报》2002年第z3期55-58,共4页Journal of the Chinese Society of Rare Earths

基　　金：上海市科技发展基金资助项目(0152NM055)

摘　　要：采用沉淀法制备了CaSO4:Eu,CaSO4:Ce,CaSO4:Eu,Ce稀土发光材料,用荧光光谱仪对发光材料的光谱特性进行了测定。首次发现并初步讨论了在CaSO4:Eu,Ce中存在Ce3+→Eu2+的能量传递和Ce3+→Eu3+的电子转移现象。研究还发现烧结温度和敏化剂的浓度对发光材料的光谱性能影响很大。单掺Eu的CaSO4:Eu体系,其发光强度随烧结温度增加而增加,表现为Eu2+的特征发光峰。烧结温度为400℃时,在CaSO4:Eu,Ce中存在Ce3+→Eu2+的能量传递和Ce3+→Eu3+的电子转移。Ce3+浓度较低时,CaSO4:Eu,Ce中Eu2+的发光强度随Ce3+离子浓度的增加而增加,Ce3+表现出很好的敏化作用;当Ce3+离子浓度超过一定范围时,CaSO4:Eu,Ce中Ce3+发光强度增大,Eu2+发光强度下降。当所制备的CaSO4:Eu,Ce荧光体烧结温度由400℃升至600℃时,Ce3+的激发与发射峰基本消失,Eu2+的荧光强度随Ce3+浓度的增加而下降。Phosphors of CaSO4: Eu, CaSO4: Ce, and CaSO4: Eu, Ce were prepared by precipitation and their excitation, emission spectra were studied. We first found that the competition between energy transfer from Ce3+ to Eu2+ and electron transfer from Ce3+ to Eu3+ exists in the CaSO4: Eu, Ce. We also noticed that the temperature of thermal treatment and the concentration of sensitizer has great effect on luminescent properties of this phosphor. In the CaSO4: Eu System, emission intensity increases with the increasing of sintering temperature, and the emission peaks are the characteristic peaks of Eu2+ ion. When the CaSO4: Eu, Ce phosphor was sintered at 400 ℃, the competition between energy transfer from Ce3+ to Eu2+ and electron transfer from Ce3+ to Eu3+ was found. When the concentration of Ce3+ ion is low, emission intensity of Eu2+ ions increases with the increasing of the concentration of Ce3+ ion, and Ce3+ ion shows sensitization. The concentration of Ce3+ ion is beyond a range, emission intensity of Ce3+ ions increase. Meanwhile, emission intensity of Eu2+ ions decrease. However, when the sintering temperature improves from 400 ℃ to 600 ℃, the excitation and emission peaks of Ce3+ ion disappears, emission intensity of Eu2+ ions decreases with the increasing of the concentration of Ce3+ ions.

关 键 词：稀土 RE: CASO4 能量传递 电子转移 热处理温度 荧光强度 

分 类 号：O614.33[理学—无机化学]