Quenching of pyrene fluorescence by fullerene C-60 in Langmuir- Blodgett films

Langmuir-Blodgett (LB) layers of pyrene and C-60 mixed with tricosanoic acid have been built-up on quartz substrates. The optical properties of the films were characterized using time-correlated single-photon counting, and absorption and steady-state fluorescence spectroscopy. Observation of negligible overlap between the emission of the donor (pyrene) and the electronic absorption spectra of the acceptor (C-60) indicates that the observed fluorescence quenching of the donor in the presence of the strong acceptor is due mainly to photo-induced electron transfer (PET) with no significant energy transfer process. The PET has been investigated by monitoring the quenching of monomer and excimer pyrene fluorescence in mixed LB films containing different concentrations of C-60. (C) 1997 Elsevier Science B.V.</p

Photoinduced electron transfer between 16-(9- anthroyloxy)palmitic acid and fullerene C-60 in Langmuir- Blodgett films

Langmuir-Blodgett (LB) layers of 16-(9-anthroyloxy)palmitic acid (Atl) and C-60 mixed with tricosanoic acid have been studied as a model system for photoinduced electron transfer (PET). The PET has been investigated by monitoring the quenching of AA fluorescence in mixed LB films containing different concentrations of C-60. Perrin's hard-sphere model adapted for the two-dimensional case provides a good fit to the experimental results, confirming the two-dimensional nature of the system. The critical radius is found to be 11 Angstrom.</p

Photo- and electroluminescence of poly(2-methoxy,5-(2 '- ethylhexyloxy)-p-phenylene vinylene) Langmuir-Blodgett films

Langmuir-Blodgett (LB) layers of poly (2-methoxy,5-(2'-ethylhexyloxy)-p-phenylene vinylene) (MEH-PPV) have been built up on quartz and indium-tin oxide (ITO) substrates. The optical properties of the films were characterized using time-correlated single-photon counting, and absorption and steady-state fluorescence spectroscopy. Electroluminescence (orange-yellow light) from ITO/MEH-PPV LB/Al devices under forward bias was observed. The dependence of the electrical and electroluminescent characteristics on LB film thickness is reported. The quantum efficiency was 7 X 10(-3)% for a device containing 64 LB layers. (C) 1998 Elsevier Science S.A. All rights reserved.</p