14.7% Efficiency Organic Photovoltaic Cells Enabled by Active Materials with a Large Electrostatic Potential DifferenceShow others and affiliations
2019 (English)In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 141, no 19, p. 7743-7750Article in journal (Refereed) Published
Abstract [en]
Although significant improvements have been achieved for organic photovoltaic cells (OPVs), the top-performing devices still show power conversion efficiencies far behind those of commercialized solar cells. One of the main reasons is the large driving force required for separating electron-hole pairs. Here, we demonstrate an efficiency of 14.7% in the single-junction OPV by using a new polymer donor PTO2 and a nonfullerene acceptor IT-4F. The device possesses an efficient charge generation at a low driving force. Ultrafast transient absorption measurements probe the formation of loosely bound charge pairs with extended lifetime that impedes the recombination of charge carriers in the blend. The theoretical studies reveal that the molecular electrostatic potential (ESP) between PTO2 and IT-4F is large, and the induced intermolecular electric field may assist the charge generation. The results suggest OPVs have the potential for further improvement by judicious modulation of ESP.
Place, publisher, year, edition, pages
AMER CHEMICAL SOC , 2019. Vol. 141, no 19, p. 7743-7750
National Category
Other Chemistry Topics
Identifiers
URN: urn:nbn:se:liu:diva-158337DOI: 10.1021/jacs.8b12937ISI: 000468366900017PubMedID: 31017418OAI: oai:DiVA.org:liu-158337DiVA, id: diva2:1333861
Note
Funding Agencies|National Natural Science Foundation of China [91633301, 51673201, 51961135103, 21805287, 21875182, 21504066, 21534003]; Chinese Academy of Science [XDB12030200, KJZD-EW-J01]; Youth Innovation Promotion Association CAS [2018043]; Ministry of Science and Technology [2016YFA0200700]; Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy [DE-AC02-05CH11231]; Swedish Energy Agency
2019-07-022019-07-022019-07-02