Stoichiometry, mobility, and performance in bulk heterojunction solar cells
2007 (English)In: Applied Physics Letters, ISSN 0003-6951, Vol. 91, no 7, 071108- p.Article in journal (Refereed) Published
Bipolar transport in blends of a copolymer of fluorene, thiophene and electron accepting groups, and the substituted fullerene [6,6]-phenyl-C61-butyric acid methylester have been studied through charge extraction by linearly increasing voltage on solar cells and with field effect transistors. Between 10% and 90% polymer has been used and the results show a clear correlation to solar cell performance. Optimal solar cells comprise 20% polymer and have a power conversion efficiency of 3.5%. The electron mobility is increasing strongly with fullerene content, but is always lower than the hole mobility, thus explaining the low amount of polymer in optimized devices.
Place, publisher, year, edition, pages
2007. Vol. 91, no 7, 071108- p.
electron mobility, field effect transistors, fullerenes, hole mobility, polymer blends, solar cells, stoichiometry
IdentifiersURN: urn:nbn:se:liu:diva-12824DOI: 10.1063/1.2771524OAI: oai:DiVA.org:liu-12824DiVA: diva2:17127