Improving Cathodes with a Polymer Interlayer in Reversed Organic Solar CellsShow others and affiliations
2014 (English)In: Advanced Energy Materials, ISSN 1614-6832, E-ISSN 1614-6840, Vol. 4, no 15, article id 1400643Article in journal (Refereed) Published
Abstract [en]
The effects of cathode modification by a conjugated polymer interlayer PFPA1 on the performance of reversed organic solar cells (substrate/cathode/active layer/transparent anode) based on different active material systems and different substrate electrodes are systematically investigated. A reduction of the work function irrespective of the substrate cathode used is observed upon the deposition of the PFPA1 interlayer, which is further related to an improved built-in electric field and open-circuit voltage. The amphiphilic character of the PFPA1 interlayer alters the surface energy of the substrate cathode, leading to the formation of a better active layer morphology aiding efficient exciton dissociation and photocurrent extraction in the modified solar cells. Hence, internal quantum efficiency is found to be significantly higher than that of their unmodified counterparts, while optically, the modified and unmodified solar cells are identical. Moreover, the deep highest occupied molecular orbital (HOMO) of the PFPA1 interlayer improves the selectivity for all investigated substrate cathodes, thus enhancing the fill factor.
Place, publisher, year, edition, pages
Wiley-VCH Verlagsgesellschaft, 2014. Vol. 4, no 15, article id 1400643
Keywords [en]
organic solar cells; polymer solar cells; interlayer modification; interfaces; selectivity
National Category
Physical Sciences Chemical Sciences
Identifiers
URN: urn:nbn:se:liu:diva-112636DOI: 10.1002/aenm.201400643ISI: 000344368500014OAI: oai:DiVA.org:liu-112636DiVA, id: diva2:769360
Note
Funding Agencies|KAW; Science Council (VR); Swedish Energy Agency; Knut and Alice Wallenberg Foundation KAW through the project Power Papers; Wallenberg Scholar grant
2014-12-082014-12-052021-07-22Bibliographically approved