DCM掺杂PVK体系的超快光谱  

Photoluminescence and Energy Transfer in DCM Doped PVK Studied by Ultra-fast Spectroscopy

作　　者：刘彭义[1] 赵福利[1] 曹玲芳[1] 连加荣[1] 周翔[1] 宋继国[1] 谢虔 许宁生[1] 

机构地区：[1]中山大学光电材料与技术国家重点实验室

出　　处：《发光学报》2005年第4期465-468,共4页Chinese Journal of Luminescence

基　　金：广州市科技计划(2004J1-C0011);广东省科技计划(B10502)资助项目

摘　　要：利用稳态荧光光谱和时间分辨超快光谱研究了DCM掺杂PVK(聚乙烯咔唑)体系的发光特性和能量转移。根据DCM的吸收光谱与PVK的荧光光谱,用F rster理论估算出DCM∶PVK掺杂体系能量转移的临界半径及其效率。在DCM∶PVK掺杂薄膜中,随着掺杂浓度的升高,DCM的发射强度增强,PVK的发射强度减弱,两者相对强度之比与估算结果一致。还利用时间分辨超快光谱研究了DCM∶PVK掺杂薄膜体系的能量转移动力学过程,观察到DCM∶PVK掺杂薄膜的荧光寿命随着掺杂浓度的升高逐渐变短。结果表明,在DCM∶PVK掺杂薄膜中,存在从PVK到DCM较为有效的F rster能量转移。Polymer light-emitting diodes （PLEDs） offer potential advantages for application in displays and lightings over other competing technologies due to their cheap and easy solution-based fabrication processing, e.g. , spin coating, screen printing or inkjet printing, which allows for the possibility of low-cost and large- area mass production. Among polymer based systems, the fluorescent/phosphorescent dye doped polymer systems have the unique advantage of simplicity and flexibility. One of methods to achieve highly efficient, full color information display is polymers doped with highly efficient fluorescent dyes, which requires a energy match but also an efficient energy transfer between polymer （host） and dye （guest）. DCM is a highly fluorescent orange-red laser dye and widely used in PLEDs as guest, and poly-vinylcarbazole （PVK） is generally used as a host material for PLEDs due to its high energy singlet or/and triplet excited states for fluorescent or/ and phosphorescent dopants, favorable film-forming properties, durability, and hole mobility. Highly efficient PLEDs with DCM doped into PVK, as a light-emitting layer, have been demonstrated due to singlet formed in the host material （PVK） which can efficiently transfer energy to the guest （DCM） via Foerster/singlet transfer processes. Recently, more attention has also been paid on the detail mechanism, e.g. energy transfer and charge trapping processes in PLEDs. Photoluminescence and energy transfer in DCM doped PVK thin films were investigated by steady-state and time-resolved ultra-fast photoluminescence. We observed that the DCM emission intensity increased and the PVK fluorescent lifetime reduced with increasing DCM doping concentration due to calculations based on Foerster energy transfer theory and the fluorescent decay data were estimated according to exponential function.

关 键 词：DCM PVK 荧光光谱 时间分辨超快光谱 能量转移 

分 类 号：TN383.1[电子电信—物理电子学] TN873.3