摘要
合成了一种新型的稀土铽配合物材料TbY(o-MBA)6(phen)2,把它作为发光材料应用于有机电致发光中。把铽配合物掺杂在导电聚合物PVK中采用旋涂法制得发光层,并利用AlQ作为电子传输层制作了多种结构的电致发光器件:器件A,ITO/PVK∶TbY(o-MBA)6(phen)2/LiF/Al;器件B,ITO/PVK∶TbY(o-MBA)6(phen)2/AlQ/LiF/Al;器件C,ITO/PVK∶TbY(o-MBA)6(phen)2/BCP/AlQ/LiF/Al。对器件A和B得到了纯正的、明亮的Tb3+离子的绿光发射,4个特征峰分别对应着能级5D4到7Fj(j=6,5,4,3)的跃迁,而PVK的发光完全被抑制。研究了掺杂体系的光致发光性能和电致发光性能,认为在光致发光中,铽的发光主要来源于PVK到稀土配合物的Frster能量传递。而在电致发光中,铽的发光主要来源于稀土配合物直接捕获载流子形成激子复合发光。并通过优化选择得到了发光性能较好的器件B,其最大亮度在14V时达到213cd·m-2。
A rare earth complex TbY （o-MBA）6 （phen）2 was synthesized, which was used as an emitting material in electroluminescence. By doping it into the conjugated polymer PVK, single-layer and doublelayer devices were fabricated with structures as follows for： device A ： ITO/PVK ： TbY （o-MBA）6（phen）2/LiF/ Al; for device B： ITO/PVK：TbY （o-MBA）6（phen）：/ AlQ/LiF/Al ; for device C ： ITO/PVK ： TbY （o-MBA）6 （phen）2/BCP/AlQ/LiF/Al. The characteristics of these devices were investigated. For single-layer and double-layer devices, the emission of PVK is completely restrained, and only the green emission from Tb^3＋ is observed in electroluminescence. The above mentioned observation is attributed to the different mechanism of electroluminescence and photoluminescence. In photoluminescence process, the energy of Tb complex may come from PVK through Forster energy transfer process, while in electroluminescence process direct sequential charge trapping appears to be the main operating mechanism. From the optimized device B, brightly green emission can be obtained, and the highest EL brightness of the device reaches 213 cd·m^-2 at 14 V.
出处
《中国稀土学报》
CAS
CSCD
北大核心
2006年第2期163-167,共5页
Journal of the Chinese Society of Rare Earths
基金
国家自然科学基金(90201004)
北京市科委资助项目(H030430020410)
河北省自然科学基金资助项目(203148)
关键词
铽配合物
电致发光
激子
稀土
terbium complex
electroluminescence （EL）
exciton
rare earths
