title: Correlation between surface photovoltage and blend morphology in polyfluorene-based photodiodes.
abstract: We present a microscopic study of photoinduced charge generation in polyfluorene-based photovoltaic structures. The sub-100 nm lateral resolution of scanning Kelvin probe microscopy allows characterizing the three-dimensional structure of thin films of blends of poly-(9,9'-dioctylfluorene-co-benzothiadiazole) (F8BT) and poly-(9,9'-dioctylfluorene-co-bis-N,N'-(4-butylphenyl)-bis-N,N'-phenyl-1,4-phenylenediamine) (PFB). From the strong correlation between surface photovoltage and blend morphology, we propose a simple model for the lateral and vertical film structure identifying in particular those regions with the most efficient conduction pathway for the photocurrent.
authors.affiliation: Cavendish Laboratory, Madingley Road, Cambridge CB3 0HE, United Kingdom.
authors.forename: Marco
authors.initials: M
authors.lastname: Chiesa
authors.forename: Lukas
authors.initials: L
authors.lastname: Bürgi
authors.forename: Ji-Seon
authors.initials: JS
authors.lastname: Kim
authors.forename: Rafi
authors.initials: R
authors.lastname: Shikler
authors.forename: Richard H
authors.initials: RH
authors.lastname: Friend
authors.forename: Henning
authors.initials: H
authors.lastname: Sirringhaus