【摘要】 通过Suzuki聚合法合成了以聚对苯为主链的含铱配合物的电磷光共轭聚合物。部分苯环单元被β-二酮结尾的烷氧基链取代,进而与2-苯基吡啶配位形成悬垂的铱配合物侧链。宽带隙的聚对苯主链使主体与客体的能级匹配,从而有利于能量的转移。铱配合物通过长β-二酮结尾的烷氧基链悬挂在聚对苯的侧链上提高了聚合物的溶解性,有利于器件的制作。另外,由于连在氧原子上的β-二酮具有较大的旋转自由度,增大了β-二酮的反应活性有利于配位反应的进行。聚合物的EL光谱只显示客体铱配合物的发射,主体的发射已被完全猝灭。这表明聚合物主体和铱配合物客体之间发生了有效的能量转移。PPPIrPPy2聚合物发光器件的EL光谱发光波长为525nm,最大外量子效率为2.6%。更多还原

【Abstract】 Electrophosphorescent light-emitting diodes,for which both singlet and triplet excitons contribute to the light emission,have attracted great scientific and commercial attention because of their high quantum efficiency.Iridium-based complexes are the popular selection as the efficient dopant due to a relatively short phosphorescent lifetime.A series of electrophosphorescent conjugated polymers based on substituted para-polyphenylenes are synthesized by Suzuki polycondensation.A part of N-alkyl benzene units were replaced by di-ketone group ended to provide a ligand for the formation of Ir complexes in side chain in the presence of 2-phenylpyridine.Poly(para-phenylene)with broad band gap makes the energy level better matching between the host and the guest.Therefore,energy transfer from the host to Ir complex becomes more efficient.The incorporation of long alkoxy group into the side-chain can substantially raise the flexibility of polymer that leads to the improvement of solubility of polymer,which is helpful for the fabrication of devices.On the other hand,the activity of β-diketone group to iridium core is raised due to more rotating freedom of β-diketone-alkyl around the oxygen atom.EL emission from the backbone of the polymers is completely quenched even though the feed content ratio of Ir-complex is as low as 1%.They all show only the emission from iridium complex,while the host emission disappeared.It indicates that efficient energy transfer from the main chain to the Ir-complex occurs.The maximum external quantum efficiency of 2.6% was achieved for PPPIrPPy2 with the feed content ratio of Ir-complex of 2% at the current density of 0.35 mA/cm2.更多还原