为了能够有效地提高电子的注入和传输能力,改善有机电致发光器件的性能,本文利用 CsN3作为 n 型掺杂剂,对有机电子传输材料 Bphen 进行 n 型电学掺杂,制备了结构为 ITO/MoO 3(2 nm)/NPB(50 nm)/Alq3(30 nm)/Bphen(15 nm)/Bphen∶CsN3(15 nm,x ％,x ＝10,15,20)/Al(100 nm)的器件.实验结果表明,CsN3是一种有效的 n 型掺杂剂,以掺杂层 Bphen∶CsN3作为电子传输层,可以有效地降低电子的注入势垒,改善器件的电子注入和传输能力,从而降低器件的开启电压,同时提高了器件的亮度和发光效率.在掺杂浓度为10％时器件的性能最优,开启电压仅为2．3 V,在7．2 V 的驱动电压下,达到最大亮度29060 cd/m2,是非掺杂器件的2．5倍以上.当驱动电压为6．6 V 时,达到最大电流效率3．27 cd/A.而当掺杂浓度进一步提高时,由于 Cs 扩散严重,发光区形成淬灭中心,造成器件的效率下降.
To enhance the electron injecting and transporting ability and improve the performance of organic light-emitting device,the organic electron transport material Bphen was electrically doped by using CsN3 as n-type dopant in this work.The devices of ITO/MoO 3 (2 nm)/NPB(50 nm)/Alq3 (30 nm)/Bphen(15 nm)/Bphen:CsN3 (15 nm,x %,x =10,15,20)/Al(100 nm)were prepared.The ex-perimental results show that the CsN3 is an effective n-type dopant.The electron injection barriers was reduced and the electron injecting and transporting ability of the device was enhanced by using the Bphen:CsN3 doped electron transport layer.As a result,the turn-on voltage was decreased,and the brightness and the luminous efficiency of the device were improved.The optimal doping concentration of the device was 10%.The device shows a turn-on voltage of 2.3 V and the maximum luminance rea-ches 29 060 cd/m2 at 7.2 V,more than 2.5 times of that of the device without doping.The maximum current efficiency was 3.27 cd/A when the voltage was 6.6 V.When the doping concentration further increases,the efficiency of the device is decreased owning to Cs atom quenching the luminescence cen-ter induced by interdiffusion.
参考文献
| [1] | 陆勍;陈炳月;杨魏强;张彤蕾;吕昭月.双电子传输层对有机发光二极管效率及其衰减的改善[J].发光学报,2015(9):1053-1058. |
| [2] | 穆晓龄;曲加伟;郭永林;梁续旭;赵毅.基于载流子平衡的效率及亮度提高的有机蓝光器件[J].发光学报,2015(8):917-922. |
| [3] | 高强;尹勇明;于晶;纪永成;闻雪梅;刘士浩;谢文法.基于双极传输母体的高效有机磷光发光器件[J].发光学报,2014(6):717-721. |
| [4] | Zhenbo Deng;S. T. Lee.Carrier transport in thin films of organic electroluminescent materials[J].Synthetic Metals,19992(2):107-109. |
| [5] | 李怀坤;张方辉;程君;丁磊.BPhen作为发光层间隔层对黄光OLED的影响[J].发光学报,2016(1):38-43. |
| [6] | 田苗苗;贺小光;祁金刚;王宁.一种高电流密度下效率不降低的绿光有机电致发光器件[J].发光学报,2015(11):1307-1310. |
| [7] | Weiying Gao;Antoine Kahn.Electronic structure and current injection in zinc phthalocyanine doped with tetrafluorotetracyanoquinodimethane: Interface versus bulk effects[J].Organic electronics,20022(2):53-63. |
| [8] | Junji Kido;Toshio Matsumoto.Bright organic electroluminescent devices having a metal-doped electron-injecting layer[J].Applied physics letters,199819/24(19/24):2866-2868. |
| [9] | 胡俊涛;程群;余承东;杨劲松;梅文娟;陆红波;王洁然.Bphen 掺杂 Cs2 CO3作为电子传输层对 OLED器件性能的影响[J].液晶与显示,2015(6):943-948. |
| [10] | Choudhury KR;Yoon JH;So F.LiF as an n-dopant in tris(8-hydroxyquinoline) aluminum thin films[J].Advanced Materials,20088(8):1456-1461. |
| [11] | Kyoung Soo Yook;Soon Ok Jeon;Chul Woong Joo.Air stable and low temperature evaporable Li3N as a n type dopant in organic light-emitting diodes[J].Synthetic Metals,200915/16(15/16):1664-1666. |
| [12] | Mei-Hsin Chen;Chih-I Wu.The roles of thermally evaporated cesium carbonate to enhance the electron injection in organic light emitting devices[J].Journal of Applied Physics,200811(11):113713-1-113713-4-0. |
| [13] | Yook, Kyoung Soo;Jeon, Soon Ok;Min, Sung-Yong;Lee, Jun Yeob;Yang, Ha-Jin;Noh, Taeyong;Kang, Sung-Kee;Lee, Tae-Woo.Highly Efficient p-i-n and Tandem Organic Light-Emitting Devices Using an Air-Stable and Low-Temperature-Evaporable Metal Azide as an n-Dopant[J].Advanced functional materials,201011(11):1797-1802. |
| [14] | J.W. Ma;Wei Xu;X.Y. Jiang.Organic light-emitting diodes based on new n-doped electron transport layer[J].Synthetic Metals,200821/24(21/24):810-814. |
| [15] | Li-Anne Liew;John Moreland;Vladislav Gerginov.Wafer-level filling of microfabricated atomic vapor cells based on thin-film deposition and photolysis of cesium azide[J].Applied physics letters,200711(11):114106-1-114106-3-0. |
| [16] | Sun, Z.;Ding, X.;Ding, B.;Gao, X.;Hu, Y.;Chen, X.;He, Y.;Hou, X..Buffer-enhanced electron injection in organic light-emitting devices with copper cathode[J].Organic electronics,20132(2):511-515. |
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