物理化学学报 >> 2011, Vol. 27 >> Issue (04): 977-982.doi: 10.3866/PKU.WHXB20110325

光化学和辐射化学 上一篇    下一篇

绿色单峰发光聚(9,9-二烯丙基芴)的合成及其发光机制

肖立新, 胡双元, 孔胜, 陈志坚, 曲波, 龚旗煌   

  1. 北京大学物理学院, 人工微结构和介观物理国家重点实验室, 北京 100871
  • 收稿日期:2010-11-19 修回日期:2010-12-27 发布日期:2011-03-29
  • 通讯作者: 肖立新,龚旗煌 E-mail:lxxiao@pku.edu.cn; qhgong@pku.edu.cn
  • 基金资助:

    国家自然科学基金(10934001, 60907015, 10821062)和国家重点基础研究发展规划项目(973) (2007CB307000, 2009CB930504)资助

Synthesis of Poly(9,9-diallylfluorene) and the Mechanism of Its Single Green Emission

XIAO Lixin, HU Shuangyuan, KONG Sheng, CHEN Zhijian, QU Bo, GONG Qihuang   

  1. State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, P. R. China
  • Received:2010-11-19 Revised:2010-12-27 Published:2011-03-29
  • Contact: Xiao Lixin,Gong Qihuang E-mail:lxxiao@pku.edu.cn; qhgong@pku.edu.cn
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (10934001, 60907015, 10821062) and National Key Basic Research Program of China (973) (2007CB307000, 2009CB930504).

摘要:

为了得到绿色单峰发光的聚合物材料, 我们设计并合成了9位取代的二烯丙基芴单体, 在NiCl2的催化下, 合成了可溶的聚芴衍生物, 聚(9,9-二烯丙基芴)(PAF). 较短的烯丙基链既可以增加聚芴的溶解度, 双键的存在又有利于聚芴发生分子间聚集而得到绿光发射的有机电致发光器件(OLED). PAF在溶液和薄膜状态下的荧光峰分别位于403和456 nm的蓝光区域, 而其器件ITO/PEDOT:PSS/PAF/LiF/Al(其中, ITO为氧化铟锡, PEDOT为聚(3,4-乙撑二氧噻吩), PSS为聚苯乙烯磺酸盐)的电致发光峰却红移至绿光区域(532 nm), 得到绿色单峰发光. 紫外吸收光谱、荧光发射光谱、红外光谱以及原子力显微镜(AFM)图像的结果证明, 造成PAF电致发绿光的机制为聚合物分子间聚集.

关键词: 聚合物, 二烯丙基芴, 绿色发光, 分子间聚集, 有机电致发光器件

Abstract:

Poly(9,9-diallylfluorene) (PAF) with single green emission was synthesized through polymerization of allyl substituted 2,7-dibromofluorene in the presence of NiCl2 as the catalyst. PAF shows deep blue fluorescence at 403 nm in solution and 456 nm in solid film state. The organic electroluminescence device (OLED) gives a green emission with the peak at 532 nm by using PAF as the emitter with a structure of ITO/PEDOT:PSS/PAF/LiF/Al (ITO: indium tin oxides; PEDOT: poly(3,4- ethylenedioxythiophene); PSS: poly(styrenesulfonate)). The photoluminescence (PL) of the PAF film red- shifted after thermal anealing, the original peak of blue emission decreased and a new peak of green emissioin increased. However, there is no change in the chemical structure based on the Fourier transform infrared (FT-IR) spectra of PAF after thermal annealing under vacuum. Moreover, there is no change on the PL spectra of PAF before and after the evaporation of metal cathode. It can be deduced that the single green emisson of PAF based OLED is original from the inter-chain aggregation which can be confirmed from their atomic force microscopy (AFM) images.

Key words: Polymer, Diallylfluorene, Green emission, Inter-chain aggregation, Organic light-emitting device