摘要
In this paper, a significant enhancement in current efficiency of the green tandem organic light-emitting diodes(TOLEDs) is demonstrated, which is based on a buffer-modified charge generation layer(CGL) of fullerene carbon(C60)/zinc-phthalocyanine(ZnPc). Al and MoO_3 were used as the buffer-modified layers on both sides of the bilayer C60/ZnPc, respectively. Experimental results show that the inserted Al and MoO_3 layers can effectively increase the electron extraction of the CGL for obtaining the device performance enhancement. Compared with that of the green TOLEDs without buffer-modified layers in CGL(37.3 cd·A~(-1)), the current efficiency of the green TOLEDs is increased to 54.1 cd·A~(-1). Further study results find that the performance can also be improved by optimizing the thickness of Al in the CGL. The maximum current efficiency and maximum luminance of the green TOLEDs achieve 63.5 cd·A~(-1) and 17 873 cd·m-2, respectively, when the multilayer structure of the CGL is Al(3 nm)/C60(5 nm)/ZnPc(5 nm)/MoO_3(3 nm).
In this paper, a significant enhancement in current efficiency of the green tandem organic light-emitting diodes(TOLEDs) is demonstrated, which is based on a buffer-modified charge generation layer(CGL) of fullerene carbon(C60)/zinc-phthalocyanine(ZnPc). Al and MoO_3 were used as the buffer-modified layers on both sides of the bilayer C60/ZnPc, respectively. Experimental results show that the inserted Al and MoO_3 layers can effectively increase the electron extraction of the CGL for obtaining the device performance enhancement. Compared with that of the green TOLEDs without buffer-modified layers in CGL(37.3 cd·A~(-1)), the current efficiency of the green TOLEDs is increased to 54.1 cd·A~(-1). Further study results find that the performance can also be improved by optimizing the thickness of Al in the CGL. The maximum current efficiency and maximum luminance of the green TOLEDs achieve 63.5 cd·A~(-1) and 17 873 cd·m-2, respectively, when the multilayer structure of the CGL is Al(3 nm)/C60(5 nm)/ZnPc(5 nm)/MoO_3(3 nm).
引文
[1]DanZhao,Huihui Liu,Yanqin Miao,HuaWang,BoZhao,YuyingHao,Furong Zhu and Bingshe Xu,Organic Electronics 32,6(2016).
[2]Takayuki Chiba,Yong-Jin Pu and Junji Kido,Topics Current Chemistry 374,33(2016).
[3]Felipe A.Angel,Jason U.Wallace and Ching W.Tang,Organic Electronics 42,102(2017).
[4]Huishan Yang,Yaoyao Yu,Lishuang Wu,Biao Qu,Wenyan Lin,Ye Yu,Zhijun Wu and Wenfa Xie,Applied Physics Express 11,022101(2018).
[5]Junji Kido,Toshio Matsumoto,Takeshi Nakada,Jun Endo,Kohichi Mori,Norifumi Kawamura and Akira Yokoi,SID Symposium Digest of Technical Papers 34,964(2003).
[6]Lu Fei-Ping,Wang Qian and Zhou Xiang,Chinese Physics B 22,037202(2013).
[7]Bi Wen-Tao,Wu Xiao-Ming,Hua Yu-Lin,H.,Sun Jin-E,Xiao Zhi-Hui,Li,Wang Li and Yin Shou-Gen,Chinese Physics B 23,017803(2013).
[8]Yonghua Chen,Jiangshan Chen,Donghang Yan,Lixiang Wang and Furong Zhu,Applied Physics Letters98,243309(2011).
[9]X.D.Gao,J.Zhou,Z.T.Xie,B.F.Ding,Y.C.Qian,X.M.Ding and X.Y.Hou,Applied Physics Letters 93,314(2008).
[10]M.Y.Chan,S.L.Lai,M.K.Fung,C.S.Lee and S.T.Lee,Applied Physics Letters 91,089902(2007).
[11]Stefan H?fle,Alexander Schienle,Christoph Bernhard,Michael Bruns,Uli Lemmer and Alexander Colsmann,Advanced Materials 26,30(2014).
[12]Yongbiao Zhao,Swee TiamTan,Demir,Hilmi Volkan Demir and Xiao Wei Sun,Organic Electronics 23,70(2015).
[13]Yu-Hao Lee,Ming-Wei Lin,Ten-Chin Wen and Tzung-Fang Guo,Journal of Applied Physics 114,154512(2013).
[14]Yonghua Chen,Qi Wang,Jiangshan Chen,Dongge Ma,Donghang Yan and Lixiang Wang,Organic Electronics 13,7(2012).
[15]Yonghua Chen,Hongkun Tian,Jiangshan Chen,Yanhou Geng,Donghang Yan,Lixiang Wang and Dongge Ma,Journal of Materials Chemistry 22,8492(2012)
[16]Lian Duan,Taiju Tsuboi,Yong Qiu,Yanrui Li,and Guohui Zhang,Optics Express 20,14565(2012).
[17]Yu-Hao Lee,Ming-Wei Lin,Ten-Chin Wen and Tzung-Fang Guo,Journal of Applied Physics 114,154512(2013).