Synthesis and properties of fluorene or carbazole-based and dicyanovinyl-capped n-type organic semiconductors
作者:Ting Qi、Yunqi Liu、Wenfeng Qiu、Hengjun Zhang、Xike Gao、Ying Liu、Kun Lu、Chunyan Du、Gui Yu、Daoben Zhu
DOI:10.1039/b715920j
日期:——
Dicyanovinyl-substituted compounds as electron transport materials are rarely studied, especially oligomers. A new series of fluorene or carbazole-based and dicyanovinyl-capped oligomers consisting of benzene or thiophene segments were synthesized using the Stille coupling reaction and their physical properties were investigated. Optical spectra show that the introduction of electron-accepting groups induces an intramolecular charge transfer, resulting in a shift of the absorption onset toward longer wavelengths. Moreover, the optical spectra of their films show intermolecular interactions, leading to bathochromic shifts with respect to the spectra in solution. Cyclic voltammetry indicates that they have suitable HOMO and LUMO energy levels, and the oligomers containing thiophene segments show lower LUMO levels. The X-ray crystallography of compound FTCN shows that the compound exhibits extended π stacking of the molecules. Thermal analysis reveals that they are thermally stable and no phase transition was observed at low temperatures.
二氰乙烯基取代化合物作为电子传输材料的研究很少,尤其是寡聚物。通过Stille偶联反应合成了一系列苯环或噻吩片段的芴或咔唑基、二氰乙烯基封端的寡聚物,并研究了它们的物理性质。光学光谱显示,引入吸电子基团诱导了分子内电荷转移,导致吸收边向长波长方向移动。此外,它们薄膜的光学光谱显示了分子间相互作用,相对于溶液中的光谱,发生了红移。循环伏安法表明,它们具有合适的HOMO和LUMO能级,而含有噻吩片段的寡聚物显示出更低的LUMO能级。FTCN化合物的X射线晶体学显示,该化合物呈现出分子广泛的π堆积。热分析表明,它们具有良好的热稳定性,在低温下没有观察到相变。