title: Accurate measurement of the exciton diffusion length in a conjugated polymer using a heterostructure with a side-chain cross-linked fullerene layer.
abstract: Exciton diffusion and photoluminescence quenching in conjugated polymer/fullerene heterostructures are studied by time-resolved photoluminescence. It is observed that heterostructures consisting of a spin-coated poly(p-phenylene vinylene) (PPV)-based derivative and evaporated C60 are ill-defined because of diffusion of C60 into the polymer, leading to an overestimation of the exciton diffusion length. This artifact is resolved by the use of a novel, thermally side-chain polymerizing and cross-linking fullerene derivative (F2D) containing two diacetylene moieties, forming a completely immobilized electron acceptor layer. With this heterostructure test system, an exciton diffusion length of 5 +/- 1 nm is derived for this PPV derivative from time-integrated luminescence quenching data.
authors.affiliation: Molecular Electronics, Materials Science Centre, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands. D.Markov@rug.nl
authors.forename: Denis E
authors.initials: DE
authors.lastname: Markov
authors.forename: Emiel
authors.initials: E
authors.lastname: Amsterdam
authors.forename: Paul W M
authors.initials: PW
authors.lastname: Blom
authors.forename: Alexander B
authors.initials: AB
authors.lastname: Sieval
authors.forename: Jan C
authors.initials: JC
authors.lastname: Hummelen
mesh_terms: D003432:Cross-Linking Reagents / Q000737:chemistry*; D004058:Diffusion; D037741:Fullerenes / Q000737:chemistry*; D015394:Molecular Structure; D011108:Polymers / Q000737:chemistry*; D013055:Spectrophotometry, Infrared
chemical_list: D003432:Cross-Linking Reagents; D037741:Fullerenes; D011108:Polymers