Unified Study of Recombination in Polymer:Fullerene Solar Cells Using Transient Absorption and Charge-Extraction Measurements
2013 (English)In: Journal of Physical Chemistry Letters, ISSN 1948-7185, Vol. 4, no 12, 2069-2072 p.Article in journal (Refereed) Published
Recombination in the well-performing bulk heterojunction solar cell blend between the conjugated polymer TQ-1 and the substituted fullerene PCBM has been investigated with pump-probe transient absorption and charge extraction of photo-generated carriers (photo-CELIV). Both methods are shown to generate identical and overlapping data under appropriate experimental conditions. The dominant type of recombination is bimolecular with a rate constant of 7 x 10(-12) cm(-3) s(-1). This recombination rate is shown to be fully consistent with solar cell performance. Deviations from an ideal bimolecular recombination process, in this material system only observable at high pump fluences, are explained with a time-dependent charge-carrier mobility, and the implications of such a behavior for device development are discussed.
Place, publisher, year, edition, pages
American Chemical Society , 2013. Vol. 4, no 12, 2069-2072 p.
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-95964DOI: 10.1021/jz4009745ISI: 000320979400014OAI: oai:DiVA.org:liu-95964DiVA: diva2:641695
Funding Agencies|Swedish Research Council||Swedish Energy Agency (STEM)||Knut and Alice Wallenberg Foundation||ERC (VISCHEM)|226136|Wallenberg Scholar grant from the Knut and Alice Wallenberg Foundation||2013-08-192013-08-122013-08-19