TY  - JOUR
A1  - Schubert, Marcel
A1  - Steyrleuthner, Robert
A1  - Bange, Sebastian
A1  - Sellinger, Alan
A1  - Neher, Dieter
T1  - Charge transport and recombination in bulk heterojunction solar cells containing a dicyanoimidazole-based molecular acceptor
N2  - Carrier transport and recombination have been studied in single component layers and blends of the soluble PPV- derivative poly[2,5-dimethoxy-1,4-phenylenevinylene-2-methoxy-5-(2-ethyl-hexyloxy)- 1,4-phenylenevinylene] (M3EH-PPV) and the small molecule acceptor 4,7-bis(2-(1-hexyl-4,5-dicyanoimidazole-2-yl)vinyl) benzo[c][1,2,5]-thiadiazole (HV-BT). Measurements on single carrier devices show significantly smaller electron mobility in the blend compared to the pure HV- BT layer, which is suggestive of the formation of isolated clusters of the acceptor in a continuous polymer matrix. The significant change in fill factor (FF) with increasing illumination intensity is consistently explained by a model taking into account bimolecular recombination and space charge effects. The decay of the carrier density after photoexcitation has been studied by performing photo-CELIV measurements on pure and blend layers. It is found that the decay at long delay times follows a power-law dependence, which is, however, not consistent with a Langevin-type bimolecular recombination of free charges. A good description of the data is obtained by assuming trimolecular recombination to govern the charge carrier dynamics in these systems.
Y1  - 2009
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/32028
UR  - http://www3.interscience.wiley.com/cgi-bin/jhome/40000761
SN  - 1862-6300
ER  -