Vertical phase separation in spin-coated films of a low bandgap polyfluorene/PCBM blend - Effects of specific substrate interaction
Journal article, 2007
We report on the effect of the substrate on the vertical phase separation in spin-coated thin films of poly [(9,9-dioctylfluorenyl-2,7-diyl)-co-5,5-4',7'-di-2-thienyl-2',1',3'-benz othiadiazole] (APFO-3) blended with [6,6]-phenyl-C-61-butyric acid methyl ester (PCBM). Compositional depth profiles of the films are measured by dynamic secondary ion mass spectrometry (SIMS). We found that changing the substrate from silicon to gold affects the composition profile near the substrate interface. This is caused by a specific interaction between the polymer (APFO-3) and the gold surface, as confirmed by X-ray photoelectron spectroscopy (XPS). The composition profile in the area away from the substrate interface, as well as the enrichment of the free surface with APFO-3, remain however unaffected by the choice of substrate. The vertical composition was also analysed for APFO-3:PCBM films spin-coated on indium tin oxide (ITO) coated with a thin layer of (3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS). (c) 2006 Elsevier B.V. All rights reserved.
thiophene
conjugated polymer
ion mass spectrometry (SIMS)
CAST PS/PMMA
SOLAR-CELLS
CONJUGATED-POLYMER BLENDS
PERFORMANCE
SELF-ASSEMBLED MONOLAYERS
X-ray photoelectron spectroscopy (XPS)
spinodal decomposition
BLENDS
adsorption
THIN-FILMS
SURFACE
MORPHOLOGY
secondary
TECHNOLOGY
THIOPHENE
Author
C. M. Bjorstrom
Karlstad University
Svante Nilsson
Karlstad University
Andrzej Bernasik
AGH University of Science and Technology
Andrzej Budkowski
Jagiellonian University in Kraków
Mats Andersson
Chalmers, Chemical and Biological Engineering, Polymer Technology
Kjell Magnusson
Karlstad University
Ellen Moons
Karlstad University
Applied Surface Science
0169-4332 (ISSN)
Vol. 253 8 3906-3912Subject Categories
Chemical Engineering
DOI
10.1016/j.apsusc.2006.08.024