PMSE 270 |
| The absorption, emission, and emission decay properties of an alkyloxy derivatized polyphenylenevinylene or “RO-PPV”, donor block (D) and an alkyl-sulfone derivatized polyphenylenevinylene or “SF-PPV” acceptor block (A) have been measured to determine the suitability of these materials in photovoltaic applications. Studies have shown that separation of exciton created upon light absorption require the formation of an intra-molecular p-i-n junction from the use of two dissimilar materials. It was found that the mixed blocks is slightly red-shifted and the emission is greatly red shifted relative to the individual donor and acceptor blocks These blocks were chemically assembled with aliphatic bridging unit and the optical properties were compared to the individual donor and acceptor blocks. The emission intensity of the bridge donor/acceptor is much lower indicating quenching of the exciton by the internal field between donor and acceptor blocks in the polymer. The emission dynamics of these materials was also studied by the concept of Time Resolved Emission Spectroscopy (TRES) with the use of Ti-Sapphire femto second laser to obtain the various lifetimes of individual materials where quenching was confirmed by the observed decrease in the lifetime of exciton emission from the –DBAB- block copolymers.
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Joint PMSE/POLY Poster Session
6:00 PM-8:00 PM, Tuesday, 12 September 2006 Moscone Center -- Hall D, Poster
Division of Polymeric Materials: Science & Engineering |