Ce^(3+)离子激活的SrB_4O_7的VUV光谱  

VUV Spectrum of Ce^(3+) Activated SrB_4O_7

作　　者：叶祥[1,2] 梁宏斌[1] 苏锵[1,3] 陶冶[4] 徐建华[4] 黄艳[4] 

机构地区：[1]中山大学光电材料及应用国家重点实验室,化学与化学工程学院 [2]广州有色金属研究院,广东广州510651 [3]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,吉林长春130022 [4]中国科学院高能物理研究所同步辐射实验室

出　　处：《发光学报》2005年第5期597-601,共5页Chinese Journal of Luminescence

基　　金：广东省科技计划基金资助项目(2003A1060101)

摘　　要：Ce3+只有一个4 f电子,具有最简单的4 f15d0基态结构,其激发光谱直接反映了5d轨道的能量状态。由于同一基质晶格相同格位上不同稀土离子受基质晶体场影响相近,所以根据Ce3+离子的光谱可以推测和分析其他稀土离子的5d轨道能量,是研究其他稀土离子f-d跃迁的基础。采用高温固相法合成了Ce3+离子激活的SrB4O7发光体,测定了样品在130~350 nm波长范围的激发光谱和相应的发射光谱。指认了VUV激发光谱上Ce3+离子的5个4 f1→4 f05d1跃迁激发带,讨论了SrB4O7的基质吸收带和Ce3+的5d轨道在SrB4O7中的晶体场劈裂、5d轨道能级重心及SrB4O7∶Ce3+的发射光谱和Stokes位移。The ground state of Ce^3＋ is 4f^15d^0, which have only one 4f electron on the configuration. For this reason, the excitation spectrum of Ce^3＋ ion directly shows the energy state of 5d level. Ce^3＋ ion can be used as a probe to investigate the f-d transitions of other rare-earth ions in same host lattice sites, since the similarity of the crystal-field effect on the 5d states of different rare earth ions in the sites. The phosphor, Ce^3＋ ion activated tetra-borate SrB4O7 , was prepared by high temperature solid-state reaction technique in present paper. Na^＋ ion was added to balance the electronic charge due to the different electronic charge value between Ce^3＋ and Sr^2＋ ions. The XRD patterns of the sample Sr0.96Ce0.02Na0.02B4O7 are in good line with the JCPDS standard card 15-801 （SrB4O7）. The VUV （vacuum ultraviolet） excitation and emission spectra were measured at the VUV spectroscopy experimental station on beam line 3B1B, Beijing Synchrotron Radiation Facilities （BSRF）, under normal operating conditions （2.2 GeV, 100 mA） at 293 K. The spectroscopic properties of this phosphor are investigated in the wavelength region 130 -400 nm. The host-related absorption is found to be about 155 nm. The five bands corresponding to the 4f^1→4f^05d^1 transitions of Ce3~ ions are identified as 277, 242, 228, 217 and 202 nm in the host lattices. Therefore, the 5d crystal field splitting and the barycenter of Ce^3＋ in the host lattice are calculated to be 13.4× 10^3 and 43.4×10^3 cm^-1 , respectively. The doublet emission bands of Ce^3＋ in the host lattice are observed at 293 and 313 nm. Hence, the Stokes shift is 1 971 cm^-1. Because SrB4O7 and SrBPO5 share iso-structural characteristics： the cations are same, and all of anions are tetrahedral AO4（A = B, P）. The spectroscopic properties of Ce^3＋ in these host lattices are compared and discussed qualitatively.

关 键 词：发光 四硼酸锶 铈 真空紫外光谱 

分 类 号：O482.31[理学—固体物理] O614.33[理学—物理]