• Journal of Integrative Natural Science
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• v.2 no.1
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• pp.32-36
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• 2009

The purpose of this project is the synthesis of dihydrosilole and its optical characterization for their applications. Dihydrosilole was synthesized from the reduction reaction of either dichlorosilole or chlorohydrosilole with lithium aluminium hydride. The reaction yield for the dihydrosilole through the latter method was higher. The optical characteristics and AIEE effect of dihydrosilole nanoaggregates was investigated for the purpose of increasing the photoluminescence efficiency. Photoluminescence efficiency of dihydrosilole nanoaggregates increased about 100 times compared to that of molecular state.

• Rapid Communication in Photoscience
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• v.4 no.3
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• pp.70-72
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• 2015

Oligomers of p-phenylene vinylene and its derivatives have drawn much attention due to their unusual emission characteristics of showing increased emission when they form into nanoparticles. We have investigated the optical properties of the oligo-(p-phenylene vinylene) and its cyano-substituted derivatives in solution and in nanoaggregate media by femtosecond and picosecond time resolved fluorescence as well as stationary spectroscopies. All the spectroscopic data are consistent with the conclusion that the cyano substitution on the ${\beta}$-position of oligo-(p-phenylene vinylene) leads to breakage of the otherwise planar structure of cyano-unsubstituted molecules, which opens up an extremely efficient, as fast as 100 fs, non-radiative relaxation channel of the excited state. Formation of the nanoaggregates reverts the effect to make the molecules planar and to block the non-radiative relaxation channel. Therefore, concerning the applications in organic electroluminescent devices and organic light emitting diodes, substitution by the cyano group is not advantageous, although such modification should be useful in respect of controlling fluorescence intensity in different media.