摘要
以中心原子为铜的磷光材料Cu4(C≡Cph)4L2[L=1,8-bis(diphenylphosphino)-3,6-dioxaoctane](简称Cu4)作为掺杂材料,选用空穴传输材料聚乙烯基咔唑(PVK)为母体材料,制作结构为ITO/Cu4∶PVK/TAZ/Mg∶Ag/Ag的双层器件,其发光颜色随掺杂的变化而改变,在较高掺杂浓度的条件下,可观察到单纯Cu4的发光,即实现了单重态到三重态的能量转移。着重讨论了主客体材料间的能量转移过程,并研究了影响器件效率的外界因素如氧气的猝灭对Cu4发光强度的影响。
Organic small molecule and polymer luminescent materials have shown great potential for commercial application of organic light-emitting diodes (OLED), due to their high luminescent level and quantum efficiency. With the development of OLED more and more attentions were attracted to improve their efficiency. Because excitons are strongly confined for molecular semiconductors, the relative spin configuration of injecting electron (spin 1/2) and hole (spin 1/2) determines the excited state properties (singlet or triplet) . Radiative decay from singlet exciton is fast and that from triplets is spin-forbidden.and.often very inefficient, but triplet emission is partially allowed in the presence of spin-orbit coupling and can be seen in molecule containing elements of high atomic number. The use of triplet emitters to improve OLED efficiency has already been proposed. Up to date, most center metal atoms are rare metals such as Pt, Ir, Ru, Re, Os etc. , but it is essential for people to find some cheaper ones to realize efficient EL emission and to decrease the cost of OLED. Cu4 displays intense emission at 520nm with a quantum yield of 0.42 in-dichloromethane. Here we reported the results of devices using a blend film of Cu4 and the hole transport polymer PVK as the emitting layer. The structure of this device is ITO/Cu4: PVK/TAZ/Mg/Al and it can realize the emission of triplet Cu4 at 516nm. The research focused on energy transfer especially on EL process and the influence of oxygen on the photoluminescence of Cu4.
出处
《发光学报》
EI
CAS
CSCD
北大核心
2003年第6期620-623,共4页
Chinese Journal of Luminescence
基金
国家自然科学基金资助项目(20125412
90101026)
