Nucleation-limited fullerene crystallisation in a polymer–fullerene bulk-heterojunction blend
Journal article, 2013
The nucleation and growth kinetics of fullerene crystals in thin films of a polymer:fullerene bulk-heterojunction blend are investigated. We find that both processes are strongly diffusion-limited at 100–110 °C due to the proximity to the glass transition temperatures of the blend components. Whereas the growth rate exponentially increases with temperature up to 230 °C, the nucleation rate displays a broad maximum around 150–170 °C, which coincides with the highest rate of fullerene crystallisation. A time-temperature-transformation (TTT) diagram reveals that across the investigated range of temperatures the low rate of nucleation is responsible for the formation of micrometre-sized crystals, which can be detrimental for polymer solar cells. Thus, we identify the lack of sufficient nucleation, which predominantly occurs on the substrate interface, as the origin of this important degradation mechanism.
Author
Camilla Lindqvist
Chalmers, Chemical and Biological Engineering, Polymer Technology
Anke Sanz-Velasco
Chalmers, Applied Physics, Electronics Material and Systems
Ergang Wang
Chalmers, Chemical and Biological Engineering, Polymer Technology
Olof Bäcke
Chalmers, Applied Physics, Eva Olsson Group
Stefan Gustafsson
Chalmers, Applied Physics, Eva Olsson Group
SuMo Biomaterials
Eva Olsson
Chalmers, Applied Physics, Eva Olsson Group
Mats Andersson
Chalmers, Chemical and Biological Engineering, Polymer Technology
Christian Müller
Chalmers, Chemical and Biological Engineering, Polymer Technology
Journal of Materials Chemistry A
20507488 (ISSN) 20507496 (eISSN)
Vol. 1 24 7174-7180Areas of Advance
Nanoscience and Nanotechnology
Energy
Materials Science
Subject Categories
Chemical Engineering
DOI
10.1039/C3TA11018D