New method for lateral mapping of bimolecular recombination in thin-film organic solar cells
2016 (English)In: Progress in Photovoltaics, ISSN 1062-7995, E-ISSN 1099-159X, Vol. 24, no 8, 1096-1108 p.Article in journal (Refereed) PublishedText
The best organic solar cells are limited by bimolecular recombination. Tools to study these losses are available; however, they are only developed for small area (laboratory-scale) devices and are not yet available for large area (production-scale) devices. Here we introduce the Intermodulation Light Beam-Induced Current (IMLBIC) technique, which allows simultaneous spatial mapping of both the amount of extracted photocurrent and the bimolecular recombination over the active area of a solar cell. We utilize the second-order non-linear dependence on the illumination intensity as a signature for bimolecular recombination. Using two lasers modulated with different frequencies, we record the photocurrent response at each modulation frequency and the bimolecular recombination in the second-order intermodulation response at the sum and difference of the two frequencies. Drift-diffusion simulations predict a unique response for different recombination mechanisms. We successfully verify our approach by studying solar cells known to have mainly bimolecular recombination and thus propose this method as a viable tool for lateral detection and characterization of the dominant recombination mechanisms in organic solar cells. We expect that IMLBIC will be an important future tool for characterization and detection of recombination losses in large area organic solar cells.
Place, publisher, year, edition, pages
John Wiley & Sons, 2016. Vol. 24, no 8, 1096-1108 p.
Bimolecular recombination, Imaging, Intermodulation, LBIC, Light beam-induced current, Organic photovoltaics, Photocurrent
Other Engineering and Technologies
IdentifiersURN: urn:nbn:se:kth:diva-186772DOI: 10.1002/pip.2770ISI: 000380164100007ScopusID: 2-s2.0-84961793680OAI: oai:DiVA.org:kth-186772DiVA: diva2:927946
FunderSwedish Research CouncilSwedish Energy AgencyKnut and Alice Wallenberg Foundation
QCR 201606022016-05-132016-05-132016-09-15Bibliographically approved