IdenTifying the nature of charge recombination in organic solar cells from charge-transfer state electroluminescence
article
Charge-transfer (CT) state electroluminescence is investigated in several polymer:fullerene bulk heterojunction solar cells. The ideality factor of the electroluminescence reveals that the CT emission in polymer:fullerene solar cells originates from free-carrier bimolecular recombination at the donor-acceptor interface, rather than a charge-trap-mediated process. The fi ngerprint of the presence of nonradiative trap-assisted recombination, a voltage-dependent CT electroluminescence quantum effi ciency, is only observed for the P3HT:PCBM system, which is explained by a reduction of the competing bimolecular recombination rate. These results are in agreement with measurements of the illumination-intensity dependence of the open-circuit voltage. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
TNO Identifier
465247
ISSN
16146832
Source
Advanced Energy Materials, 2(10), pp. 1232-1237.
Collation
6 p.
Pages
1232-1237
Files
To receive the publication files, please send an e-mail request to TNO Repository.