Low-temperature single-molecule spectroscopy of MEH-PPV conjugated polymer molecules

被引:84
作者
Yu, Zhonghua [1 ,2 ]
Barbara, Paul F. [1 ]
机构
[1] Department of Chemistry, Ctr. Nano-/Molec. Sci./Technology, University of Texas, Austin
[2] Department of Chemistry, City College of New York, New York
关键词
D O I
10.1021/jp038005g
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学科分类号
摘要
Relatively narrow bandwidth fluorescence spectra were observed from isolated single molecules of the conjugated polymer, MEH-PPV (poly[2-methoxy-5-(2′-ethyl-hexyloxy)-1,4-phenylene vinylene]) at low temperature. The spectroscopy reveals rich spectral information in energy relaxation pathways and structure of this important electroluminescent material. From room temperature to 20 K the fluorescence of MEH-PPV molecules was found to red-shift by ∼20 nm along with a decreased electron-phonon coupling. The fluorescence spectra give clear evidence for efficient electronic energy funneling to a small number (one in some cases) of low-energy sites, each with an increased effective conjugation length compared to room temperature.
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页码:11321 / 11326
页数:5
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共 38 条
[11]  
Woo H.S., Lhost O., Graham S.C., Bradley D.D.C., Friend R.H., Quattrocchi C., Bredas J.L., Schenk R., Muellen K., Synth. Met., 59, (1993)
[12]  
Collison C.J., Rothberg L.J., Treemaneekarn V., Li Y., Macromolecules, 34, (2001)
[13]  
Wang P., Cuppoletti C.M., Rothberg L.J., Synth. Met., 137, (2003)
[14]  
Xie X.S., Trautman J.K., Annu. Rev. Phys. Chem., 49, (1998)
[15]  
Moerner W.E., Orrit M., Science, 283, (1999)
[16]  
Hu D., Yu J., Wong K., Bagchi B., Rossky P.J., Barbara P.F., Nature, 405, (2000)
[17]  
Huser T., Yan M., Rothberg L.J., Proc. Natl. Acad. Sci. U.S.A., 97, (2000)
[18]  
Mehta A., Kumar P., Dadmun M.D., Zheng J., Dickson R.M., Thundat T., Sumpter B.G., Barnes M.D., Nano Lett., 3, (2003)
[19]  
Hofkens J., Maus M., Gensch T., Vosch T., Cotlet M., Kohn F., Herrmann A., Mullen K., De Schryver F., J. Am. Chem. Soc., 122, (2000)
[20]  
Cotlet M., Gronheid R., Habuchi S., Stefan A., Barbafina A., Mullen K., Hofkens J., De Schryver F.C., J. Am. Chem. Soc., 125, (2003)