Electron transfer between adjacent layers in self-assembled films

A simple model of electron transfer is adapted to explain fluorescence quen ching in self-assembled films of poly( p-phenylene vinylene) (PPV) alternat ing with poly(thiophene acetic acid) (PTAA). Quenching is caused by a photo -induced electron transfer between the excited PPV (donor, D) and the PTAA (acceptor, A). The electron-transfer process can be mediated by insertion o f electronically inert spacing bilayers between the D and A layers, As the number of bilayers is increased, the fluorescence is gradually recovered wh ich is explained theoretically by assuming that the electron-transfer rate can be described as k = Z exp(- beta r) where r is the distance between D a nd A. (C) 2000 Elsevier Science B.V. All rights reserved.