聚合物/磷光复合体电致发光进展

Progress of Research of Electroluminescent Devices on Polymer/Phosphorescent Complexes

聚合物/磷光复合体电致发光是近几年来受到广泛关注的新兴领域。从主客体材料的特点、发光机理、器件结构几个方面综合阐述了该领域的研究概况。磷光材料在发光过程中可以利用单线态和三线态激子,理论上内量子效率达到100%,这类材料的使用成为提高器件效率的主要途径之一。聚合物母体的选择应满足能量匹配原理,并且应具有良好的载流子迁移性质。所有的磷光材料都能作为客体使用,这方面聚合物母体优于小分子母体。另外,枝化及高分子化的磷光材料既能抑制自猝灭,又能保证有效的能量转移,是一类大有前途的新型发光材料。由于器件的电致发光包括F ster能量转移和载流子直接在客体上复合两种机理,而磷光材料激发态的特点是长寿命,因此设计器件结构时应考虑激子的相互作用与猝灭问题。

Electroluminescent devices based on polymer/phosphorescent complexes have become a novel and attractive area of research in recent years. In this review, characteristics of both polymer matrices and phosphorescent dopants, the electrophosphorescent mechanism and device structure have been introduced. The advantage of phosphorescent materials is that they can utilize both singlet and triplet exciton states which can reach 100% internal quantum efficiency theoretically. The system requires polymer matrices satisfy energy matching between polymer host and phosphorescent dopant and have good carrier mobility. All the phosphorescent materials can be used as dopants for EL devices, which is a significant advantage of polymer host over small molecule host. Grafting and incorporating phosphorescent polymers can be used as a novel kind of luminescence materials with less selfquenching and more efficient energy transfer. Electroluminescence of these devices is from both Fster energy transfer and exciton directly recombination on the dopant, so it is necessary to be in view of the interaction and selfquenching of the excitons while designing the suitable structures of devices.