title: Effect of thermal annealing on exciton diffusion in a diketopyrrolopyrrole derivative.
abstract: We show that the method we have developed for measuring the singlet exciton diffusion length in blends with [6,6]-phenyl-C(61)-butyric acid methyl ester (PCBM) can be applied not only to polymeric materials, but also to small molecule organic semiconductors. Small organic molecules have a large potential for molecular re-organization upon thermal annealing. Here we show that the exciton diffusion length is decreased upon annealing from 9 to 3 nm in a thin film of a diketopyrrolopyrrole derivative. Such a variation is attributed to exciton delocalization effects in the crystalline domains that are formed during the annealing process as well as to the exciton quenching at grain boundaries.
authors: Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh, The Netherlands. alex@mikhnenko.com
authors: Oleksandr V
authors: OV
authors: Mikhnenko
authors: Jason
authors: J
authors: Lin
authors: Ying
authors: Y
authors: Shu
authors: John E
authors: JE
authors: Anthony
authors: Paul W M
authors: PW
authors: Blom
authors: Thuc-Quyen
authors: TQ
authors: Nguyen
authors: Maria Antonietta
authors: MA
authors: Loi