Dynamic quenching of 5-(2 '-ethyl-hexyloxy)-p-phenylene vinylene (MEH-PPV)by charge transfer to a C-60 derivative in solution

The fluorescence of 5-(2 ' -ethyl-hexyloxy)-p-phenylene vinylene (MEH-PPV) quenched in solution in 1,2-dichlorobenzene by a soluble derivative of C-60 [1-(3-methoxycarbonyl)propyl-1-phenyl[6,6]C-61; [6,6]PCBM] is studied by c hanging the concentration of the quencher and by varying the temperature. F or MEH-PPV and PCBM dissolved in 1,2-dichlorobenzene, the Stern-Volmer cons tant (K-SV) is 2 x 10(3)M(-1). At high temperature, K-SV is enhanced becaus e thermal energy facilitates the diffusion of PCBM. The results show that d ynamic quenching (rather than static quenching) is the basic mechanism. Com parison with data obtained from quenching studies of trans-stilbene indicat es that a single acceptor in contact with an MEH-PPV macromolecule quenches the luminescence from hundreds of repeat units. (C) 2001 John Wiley & Sons , Inc.