No abstract

KIMbPPV was sensitized by ethyl viologen which is well known as a good electron acceptor, to achieve efficient ionization of the excitons created by photoexcitation of PPV. PPV/ethyl-viologen composites were successfully prepared from PPV-precursor and ethyl-viologen because both compounds could be soluble in polar solvents such as methanol, water etc. We observed dramatic decrease of photoluminescence efficiency in the PPV/ethyl-viologen composite film as compared with PPV film. This is attributed to photoinduced electron transfer in PPV/ethyl-viologen composites and the efficient ionization of the excitons was occurred in this composite film. Time-resolved photoluminescence of composite films was also studied to obtain the information of this photoinduced electron transfer dynamics.