利用Cs基衍生物作为n型掺杂剂改善蓝色有机发光二极管的效率(英文)  

Improving the Efficiency of Blue Organic Light-Emitting Diodes by Employing Cs-Derivatives as the n-Dopant

作　　者：申利莹[1] 吴晓明[1] 华玉林[1] 董木森[1] 印寿根[1] 郑加金[2] 

机构地区：[1]天津理工大学材料科学与工程学院,显示材料与光电器件教育部重点实验室,光电材料与器件天津市重点实验室,天津300384 [2]南京邮电大学光电工程学院,南京210003

出　　处：《物理化学学报》2012年第6期1497-1501,共5页Acta Physico-Chimica Sinica

基　　金：supported by the National Natural Science Foundation of China(60906022,60676051);Natural Science Foundation of Tianjin, China(10JCYBJC01100);Scientific Developing Foundation of Tianjin Education Commission,China(2011ZD02);Jiangsu Natural Science Development Foundation for University,China(09KJB140006)~~

摘　　要：利用两种Cs基衍生物碳酸铯(Cs2CO3)和醋酸铯(CH3COOCs)作为n型掺杂剂掺入到一种新型的电子传输材料2,9-二(2-萘基)-4,7-二苯基-1,10-菲啰啉(NBPhen)中来提高有机发光二极管(OLEDs)的效率.实验结果表明:器件的驱动电压明显降低,并且优化后得到的Cs基n型掺杂器件(ITO/β-NPB/CBP:5%(w)N-BDAVBi/NBPhen/NBPhen:Cs2CO3(or CH3COOCs)/Al)呈现出较好的电致发光性能,在14 V时电流密度分别为551.80和527.88 mA·cm-2,对应的亮度分别达到39750和39820 cd·m-2,电流效率在亮度为10000 cd·m-2时分别为14.60 cd·A-1(Cs2CO3掺杂)和14.40 cd·A-1(CH3COOCs掺杂),这些参数明显优于传统器件的发光性能(ITO/β-NPB/CBP:5%(w)N-BDAVBi/NBPhen/Cs2CO3/Al,其在14 V时电流密度为312.39 mA·cm-2,对应的亮度为25190 cd·m-2;电流效率在亮度为10000 cd·m-2时为9.45 cd·A-1.此外,基于有机半导体掺杂原理和器件的能级结构对n型掺杂器件效率提高的原因进行了分析.The efficiency of organic light-emitting diodes（OLEDs） was markedly improved using the novel electron transporting material 2,9-bis（naphthalen-2-yl）-4,7-diphenyl-1,10-phenanthroline（NBPhen） doped with Cs-derivatives including cesium carbonate（Cs2CO3） and cesium acetate（CH 3 COOCs） as the n-type dopant.The operating voltage of devices containing these materials as an n-type electron transporting layer（n-ETL） was significantly reduced.Optimized devices with Cs2CO3-doped or CH3 COOCsdoped n-ETL（ITO/β-NPB/CBP：5%（w） N-BDAVBi/NBPhen/NBPhen：Cs2CO3（or CH 3 COOCs）/Al） exhibited excellent electroluminescent performance with current densities of 551.80 and 527.88 mA·cm-2 at 14 V,corresponding brightnesses of 39750 and 39820 cd·m-2,and current efficiencies of 14.60 and 14.40 cd·A-1 at 10000 cd·m-2,respectively.These results were superior to that of conventional device（ITO/β-NPB/CBP：5%（w）N-BDAVBi/NBPhen/Cs2CO3 /Al） without an n-ETL,which exhibited a current density of 312.39 mA·cm-2 at 14 V,corresponding brightness of 25190 cd·m-2,and current efficiency of 9.45 cd·A-1 at 10000 cd·m-2.In addition,the reason for the increase in the efficiency of n-type doped devices has been analyzed based on the concept of the doping mechanism in organic semiconductors and the energy level scheme of the devices.

关 键 词：有机发光二极管 碳酸铯 醋酸铯 n型电子传输层 电致发光性能 

分 类 号：TN312.8[电子电信—物理电子学]