Article

Enhanced Emission and Its Switching in Fluorescent Organic Nanoparticles

Gyeongsang National University, Shinshū, Gyeongsangnam-do, South Korea
Journal of the American Chemical Society (Impact Factor: 11.44). 01/2003; 124(48):14410-5. DOI: 10.1021/ja0269082
Source: PubMed

ABSTRACT A new class of organic nanoparticles (CN-MBE nanoparticles) with a mean diameter of ca. 30-40 nm, which exhibit a strongly enhanced fluorescence emission, were prepared by a simple reprecipitation method. CN-MBE (1-cyano-trans-1,2-bis-(4'-methylbiphenyl)ethylene) is very weakly fluorescent in solution, but the intensity is increased by almost 700 times in the nanoparticles. Enhanced emission in CN-MBE nanoparticles is attributed to the synergetic effect of intramolecular planarization and J-type aggregate formation (restricted excimer formation) in nanopaticles. On/off fluorescence switching for organic vapor was demonstrated with CN-MBE nanoparticles.

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