三重态发光材料Cu4掺杂的PVK发光器件及特殊的发光增强机理研究

多种有机发光材料已被应用于电致发光（EL）器件的制备，其荧光效率远比无机发光材料高。与光激发直接产生单重态洋鬼子不同，电致发光过程是电子空穴分别由相反极性的电极注入（非成对电子注入），三重态和单重态激子同时生成，按自旋统计理论预测，三重态和单重态子的比例为3：1。由于三重态的跃迁是自旋禁阻的，大部分有机分子的三重态激子发光效率极低，有机电致发光器件的最高交率限制在25％（对于光致发光效率100％的理想情况）。为进一步提高器件效率，人们开始设想和实施对通常认为是无效激发的75％的三重激发态进行利用，其关键是筛选出适于器件应用的高效率三重态发光材料，据此我们选择过渡金属配合物Cu4(C≡CPh4)4L2[L=1,8-bis9diphenyl phosphino)-3,6-dioxaoctane]（以下简称Cu4）进行了器件性能研究。

Electroluminescent Devices Based on Triplet Materials Cu4 Doped PVK and Special Increasing Emitting Mechanism

The bilayer devices using a mixture film of triplet emitting material Cu4(C≡CPh4)4L2［L=1,8-bis(diphenyl phosphino)-3,6-dioxaoctane］(Cu4) and hole transport polymer poly(9-vinylcarbazole)(PVK) as emitting layer, electron transport material TAZ as the electron transport layer were prepared. Different devices that formed by varied Cu4 ratios show different light emitting properties through singlet-triplet and triplet-triplet energy transfer. The result showed a new application of triplet emitting materials.