Yunlong Guo, Huaping Zhao, Gui Yu,* Chong-an Di, Wei Liu, Shidong Jiang, Shouke Yan, Chunru Wang, Hongliang Zhang, Xiangnan Sun, Xutang Tao*, and Yunqi Liu*

We synthesized a soluble 2,8-di(4-trifluoromethylphenyl)-5,11-di-n-octylindolo[3,2-b]carbazole (2TFMPOIND) and grew its single-crystals. X-ray diffraction measurements indicate that strong cofacial p–p stacking, alkyl-alkyl close contacts, and F×××H hydrogen bonds exist between two neighbouring molecules. The 2TFMPOIND molecules form one dimensional macroribbons via a solution-phase self-assembly processing. Moreover, the single crystal has novel mechanical, optical, and electrical properties. The micro single crystal can be bended by machine probe in different directions, and has bright fluorescence, which can be propagated over 100 mm along the length direction. Field-effect transistors based on an individual microribbon showed a moderate mobility (0.019-0.084 cm² V^-1 s^-1), whose mean value was 0.034 cm² V^-1 s^-1. Meanwhile, the transistors exhibited threshold voltages from -4.0 to -16.0 V.

Advanced Materials  2008, 20, 4835-4839

Figure  Left, solution-grown one-dimension single-crystal micro-ribbons; up-right, field-effect transistor made by an individual single-crystal micro-ribbon and current-voltage curves; bottom-right, waveguide characteristic of individual single-crystal micro-ribbon.