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Vertically Aligned Organic Nanowires: Patterned Growth for Sensing and Waveguiding

Jiaxing Huang, Dept. of Materials Science and Engineering, Northwestern University

1,5-diaminoanthraquinone (DAAQ) molecules can self-assemble into vertically aligned organic nanowires via a facile physical vapor transport method. Physical and chemical patterning of a substrate can induce selective growth of the nanowires on high surface energy area.

Electron and X-ray diffraction analysis determined that the nanowire is single crystalline with a monoclinic unit cell.

The nanowire can serve as an optical waveguide to propagate its photoluminescence (left). The fluorescence of the DAAQ nanowires can be quenched by acid vapor and rapidly regenerated by base vapor, making them useful as optical sensor materials (top).

Physical patterning

Chemical patterning

PL intensity upon exposure to HCl vapor

Y. S. Zhao et al. J. Am. Chem. Soc., 2009, 131, 3158.Y. S. Zhao et al. ACS Nano, 2010, 4, 1630; J. Wu et al. Ultramicroscopy, in press.