Realizing efficient bipolar deep-blue light-emitting poly(2,7-carbazole) derivatives by suppressing intramolecular charge transfer

被引：10

作者：

Peng, Feng ^{[1
,2
]}

Wang, Xiaojun ^{[1
]}

Guo, Ting ^{[1
]}

Xiong, Jian ^{[3
]}

Ying, Lei ^{[1
]}

Cao, Yong ^{[1
]}

机构：

[1] South China Univ Technol, Inst Polymer Optoelect Mat & Devices, State Key Lab Luminescent Mat & Devices, Guangzhou 510640, Guangdong, Peoples R China

[2] South China Inst Collaborat Innovat, Dongguan 523808, Peoples R China

[3] South China Univ Technol, Sch Food Sci & Engn, Guangzhou 510640, Guangdong, Peoples R China

来源：

ORGANIC ELECTRONICS | 2019年 / 67卷

基金：

中国国家自然科学基金; 国家教育部博士点专项基金资助;

关键词：

Blue light-emitting polymers; Twisted structure; Bipolar; Poly(2,7-carbazole); Charge transfer effect; POLYMER; HOSTS; ELECTROLUMINESCENCE; TRANSPORT; DEVICES;

D O I：

10.1016/j.orgel.2019.01.004

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Two series of twisted bipolar poly(2,7-carbazole) derivatives, namely PCz-37RSOs and PCz-28SOs, were synthesized by introducing electron-deficient 2,8-dioctyl- di-benzothiophene-S,S-dioxide-3,7-diyl (37RSO) and dibenzothiophene- S,S -dioxide - 2,8-diyl (28S0) unit into poly(9-heptadecanyl-2,7-carbazole) (PCz) backbone, respectively. The incorporation of electron-withdrawing 37RSO and 28S0 into PCz backbone decreased effective conjugation length, and further restrained charge transfer effect existed in dipolar system, simultaneously, the balanced charge carrier injection/transportation were realized due to the eletrophilicity of SO unit. Consequently, the resulting polymers showed hypsochromic shift and narrowed emission spectra regarding to PCz-37 SOs that contains linear SO unit in main chain, and exhibited balanced hole/electron fluxes with respect to PCz in the range of 0-10 V. The single-layer devices based on resulting bipolar polymers exhibited excellent electroluminescent spectra stability in the current densities from 100 to 400 mA cm(-2), and displayed deep blue electroluminescence spectra with the Commission Internationale de L' Eclairage (CIE) of (0.16, 0.07) for PCz-37RS05 and (0.16, 0.09) for PCz-28S05. The superior device performance was achieved with the maximum luminous efficiency (LEmax) of 2.69 cd A(-1) for PCz-28S020, which obviously outperformed that of 0.24 cd A(-1) for PCz. These results indicated that twisted molecular structure design is a promising strategy for efficient deep blue light-emitting polymers.

引用

页码：34 / 42

页数：9

共 37 条

[1] Efficient Blue, Green, and Red Electroluminescence from Carbazole-Functionalized Poly(spirobifluorene)s [J].