以聚乙烯亚胺作为电子注入层的有机-无机复合发光器件  

Hybrid organic-inorganic light-emitting diodes based on a polythylenimine interlayer

作　　者：雷勇[1] 王瑞雪[1] 范昌君 杨晓晖[1] 

机构地区：[1]西南大学物理科学与技术学院,重庆400715

出　　处：《科学通报》2016年第7期740-747,共8页Chinese Science Bulletin

基　　金：国家自然科学基金(61177030;11474232);教育部新世纪优秀人才支持计划(NCET-11-0705);西南大学博士基金(SWU111057)资助

摘　　要：聚乙烯亚胺(PEIE)能有效地提高有机-无机复合发光器件中氧化锌对发光聚合物特别是具有较低电子亲和势蓝色发光聚合物的电子注入效率,以PEIE作为电子注入层的有机-无机复合发光器件具有与采用低功函数金属阴极的传统结构器件接近的发光效率.有机-无机复合磷光器件的外量子效率为19.1%,为目前该类器件的最高效率.Implementation of a polyethylenimine ethoxylated （PEIE） interlayer significantly enhances electron injection efficiency from ZnO into light emitting polymers including a blue light emitting polymer with relatively low electron affinity, verified by comparison of current density-voltage characteristics of the electron-only devices with or without a PEIE interlayer. Ultraviolet photoelectron spectroscopy measurements reveal that PEIE forms interracial dipoles and reduces the work function of ZnO by ca. 1.2 eV, thus facilitating electron injection into light emitting polymers. Neutralized amines rather than protonated amines are responsible for the formation of interfacial dipoles as manifested by Nls core level spectra of the ZnO/PEIE sample. Luminance efficiency of hybrid organic-inorganic light emitting devices employing PEIE interlayer is similar to that of the analogous conventional devices with low work-function metal cathode due to electron injection promoting and hole/exciton-blocking properties of PEIE. Compared to Cs2CO3, PEIE, which possesses similar surface energy to the organic materials and can form homogeneous film, is expected to collaborate with the adjoining organic layers, without significantly interrupting their morphology, especially for those containing low molecular weight components such as phosphorescent emitters. We envisage that this valuable tribute enables the use of small molecule light emitting materials for device fabrication and is particularly beneficial for the effective introduction of phosphorescent emitters into the emission layer of organic-inorganic light emitting devices. Phosphorescent hybrid organic-inorganic light emitting devices with solution-processed 4,4＇,4 -tris（carbazol-9-yl）tdphenyl-amine （TCTA）： 1,3-bis[（4-tert-butylphenyl）-1,3,4-oxadiazolyl]phenylene （OXD-7）： Ir-complex emission layer show the maximum luminance efficiency of 64 cd/A and external quantum efficiency of 19.1%, which represent the best efficiency for organic-inorganic light e

关 键 词：有机-无机复合发光器件 电子注入层 发光聚合物 溶液加工方法制备小分子材料发光层 

分 类 号：TQ422[化学工程]