C.V. and M.T. thank Prof. S. Yamaguchi and Dr A.
Fukazawa for measurement of fluorescence quantum yields.
Notes and references
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Fig. 3 SEM images of 1 drop casted from chloroform–toluene
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LUMO of DNT and TNT were found to be ꢁ3.3 and ꢁ3.8 eV,
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transfer is possible between 1 and quencher molecules resulting
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the photoinduced electron transfer between 1 and the quenchers
is 1.6 and 2.1 eV for DNT and TNT, respectively.
In summary,
a fluorescent charge transfer molecule
consisting of binaphthyl functionalized with donor–acceptor
substituted stilbenes was designed and synthesized. The charge
transfer induced fluorescence of this molecule was quenched
on exposure to explosive vapors such as DNT or TNT as a
result of photoinduced electron transfer which allows the
detection of the latter. The sensing efficiency was significantly
enhanced by self-assembly assisted morphology tuning.
This work illustrates the application of self-assembly for the
enhancement of functional properties of organic molecules to
make them suitable for useful applications.
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Fig. 4 (a) Fluorescence quenching of 1 when exposed to DNT (black)
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10 See supporting information.
ꢂc
This journal is The Royal Society of Chemistry 2010
876 | Chem. Commun., 2010, 46, 874–876