La_2CaB_(10)O_(19):Ce^(3+)在VUV-Vis范围的发光性质研究  

Luminescence Property of La_2CaB_(10)O_(19):Ce^(3+) in VUV-Vis Range

作　　者：赫泓[1] 梁宏斌[2] 陶冶[3] 王淑彬[1] 苏锵[1] 

机构地区：[1]中国科学院长春应用化学研究所稀土化学与物理重点实验室,长春130022 [2]中山大学化学与化工学院.光电材料和技术国家重点实验室.广州,510275 [3]中国科学院高能物理研究所.北京同步辐射实验室,北京100039

出　　处：《高等学校化学学报》2003年第9期1541-1543,共3页Chemical Journal of Chinese Universities

基　　金：国家重点基础研究规划项目(批准号;G1998061312);北京同步辐射实验室重点课题(批准号:01049)资助

摘　　要：通过研究La_2CaB_(10)O_(19):Ce^(3+)在VUV-Vis范围的光谱.发现Ce^(3+)在La_2CaB_(10)O-(19)中共有两种格位.分别取代了十配位的I。a’“和八配位的Ca”,从而发射光谱中没有出现特征的双峰,而出现了峰值约位于307,330和 356 nm的3个发射峰.由于在低对称性晶体场中d轨道的分裂.激发光谱中位于194.224,243.260,274和318 nm的峰是由两个格位的Ce^(3+)的f-d跃迁引起的.Ce^(3+)占据两个格位,可以通过以Eu^(3+)为荧光探针的发射光谱中出现的两个~5D_(0-)~7F_0跃迁得到验证.峰值位于162 nm的激发谱带是基质吸收带.与基质禁带宽度相对应.通过计算,不排除其中包含O^(2-)→Ce^(3+)的电荷迁移带的可能性.The excitation and emission spectra of La2CaB10O19 : Ce3+ in VUV-Vis range were investigated. Three bands peaking at 307, 330 and 356 nm in emission spectrum and six bands peaking at 194, 224, 243, 260, 274 and 318 nm in excitation spectra are observed. This fact indicates that Ce3+ ions occupy two kinds of lattice sites in La2CaB10O19, one kind is substituted for La3+ with coordination number ten and the other is substituted for Ca2+ with coordination number eight. This result is consistent with that of La2CaB10O19: Eu3+. When Eu3+ is used as a structural probe, two 5D0→7F0 transitions peaking at 576. 8 and 578. 8 nm are observed in the emission spectrum. This indicates that Eu3+ ions also occupy two kinds of lattice sites in La2CaB10O19. The broad band peaking at 162 nm can be attributed to the host absorption, and the charge transition band(CTB) of O2-→Ce3+ may be obscured in this broad band.

关 键 词：La2CaB10O19:Ce3+ VUV-Vis范围 发光性质 硼钙锎复合盐 配位化合物 晶格 

分 类 号：O641.4[理学—物理化学]