Ce^(3+)激活的LiSrBO_3材料发光特性及晶体学格位研究  

Luminescent Characteristics and Crystallographic Sites of Ce^(3+) Activated LiSrBO_3 Phosphor

作　　者：李盼来[1] 王志军[1] 王颖[1] 杨志平[1] 郭庆林[1] 

机构地区：[1]河北大学物理科学与技术学院,保定071002

出　　处：《高等学校化学学报》2009年第8期1487-1491,共5页Chemical Journal of Chinese Universities

基　　金：河北省科学技术发展基金(批准号:51215103b);河北省自然科学基金(批准号:E2009000209);河北大学青年基金(批准号:2006Q06)资助

摘　　要：采用固相法制备了蓝白色LiSrBO3∶Ce3+材料.测得LiSrBO3∶Ce3+材料的发射光谱为一个主峰位于436 nm的非对称单峰宽谱;监测436 nm发射峰时所得材料的激发光谱为一个主峰位于369 nm的宽谱.利用Van Uitert公式计算了Ce3+取代LiSrBO3中Sr时所占晶体学格位,得出433 nm发射带归属于九配位的Ce3+发射,469 nm发射带起源于八配位的Ce3+发射.研究了Ce3+浓度对LiSrBO3∶Ce3+材料发光强度的影响,研究结果显示,随着Ce3+浓度的增大,发光强度呈现先增大后减小的趋势,在Ce3+摩尔分数为3%时到达峰值,根据Dexter理论,其浓度猝灭机理为电偶极-偶极相互作用.引入Li+,Na+和K+作为电荷补偿剂时发现,LiSrBO3∶Ce3+材料的发射光谱强度均得到了明显的增强.利用InGaN管芯(370 nm)激发LiSrBO3∶Ce3+材料时,获得了很好的蓝白光发射,色坐标为(x=0.289,y=0.293).The blue white LiSrBO3： Ce^3＋ phosphor was synthesized with solid-state method. The emission spectrum of LiSrBO3： Ce^3＋ phosphor shows one dissymmetrical band at 436 nm. The excitation spectrum for 436 nm emission has broad band at 369 nm. The crystallographic sites of Ce^3＋ in LiSrBO3 were calculated by Van Uitert formula. The results show that the emission band centered at 433 nm originates from the Ce^3＋ center of the nine compounds, the other emission band centered at 469 nm originates from the Ce^3 ＋ center of the eight compounds. The effect of Ce^3 ＋ molar fraction on luminescent intensity of LiSrBO3 ： Ce^3 ＋ phosphor was in- vestigated, the result shows that the luminescent intensity firstly increases with increasing Ce^3 ＋ molar fraction, then decreases, and reaches the maximal value at 3% Ce^3＋. The concentration quenching mechanisms are the D-D interaction by Dexter theory. Under the condition of doping charge compensation Li^＋, Na^＋ and K^＋ , the emission spectrum intensity of LiSrBO3 ： Ce^3＋ was heightened. The relative emission spectrum of the blue white-emitting InGaN-based LiSrBO3： Ce^3＋ LED was investigated, and the CIE chromaticity of lnGaN-based LiSrBO3 ： Ce^3＋ LED is x = 0. 289, y = 0. 293.

关 键 词：白光LED LiSrBO3∶Ce3+ 晶体学格位 发光特性 

分 类 号：O614[理学—无机化学] O482.31[理学—化学]