title: Charge separation in semicrystalline polymeric semiconductors by photoexcitation: is the mechanism intrinsic or extrinsic?
abstract: We probe charge photogeneration and subsequent recombination dynamics in neat regioregular poly(3-hexylthiophene) films over six decades in time by means of time-resolved photoluminescence spectroscopy. Exciton dissociation at 10 K occurs extrinsically at interfaces between molecularly ordered and disordered domains. Polaron pairs thus produced recombine by tunneling with distributed rates governed by the distribution of electron-hole radii. Quantum-chemical calculations suggest that hot-exciton dissociation at such interfaces results from a high charge-transfer character.
authors.affiliation: Département de physique and Regroupement québécois sur les matériaux de pointe, Université de Montréal, C.P. 6128, Succursale centre-ville, Montréal (Québec), H3C 3J7, Canada.
authors.forename: Francis
authors.initials: F
authors.lastname: Paquin
authors.forename: Gianluca
authors.initials: G
authors.lastname: Latini
authors.forename: Maciej
authors.initials: M
authors.lastname: Sakowicz
authors.forename: Paul-Ludovic
authors.initials: PL
authors.lastname: Karsenti
authors.forename: Linjun
authors.initials: L
authors.lastname: Wang
authors.forename: David
authors.initials: D
authors.lastname: Beljonne
authors.forename: Natalie
authors.initials: N
authors.lastname: Stingelin
authors.forename: Carlos
authors.initials: C
authors.lastname: Silva