Berlin 2012 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
HL: Fachverband Halbleiterphysik
HL 2: Focus Session: Structural Ordering and Electronic Transport I (jointly with CPP)
HL 2.9: Talk
Monday, March 26, 2012, 12:30–12:45, ER 270
Morphology triggered impact of charge carrier recombination on the current–voltage response of organic solar cells — •Alexander Foertig1, Markus Gluecker1, Alexander Wagenpfahl1, Carsten Deibel1, and Vladimir Dyakonov1,2 — 1Experimental Physics VI, Julius-Maximilians-University of Würzburg, Am Hubland, 97074 Würzburg, Germany — 2Bavarian Centre for Applied Energy Research (ZAE Bayern e.V.), Am Hubland, 97074 Würzburg, Germany
In view of a commercialization the efficiency of organic solar cells still has to be improved. Therefor a proper understanding of the fundamental physical processes is required. The non-geminate loss mechanisms of photo-generated charges in polymer:fullerene bulk heterojunction solar cells are studied using the complementary measurement techniques charge extraction (CE), transient photovoltage (TPV) and transient photocurrent (TPC). From voltage dependent charge carrier densities n(V) a loss current jloss(V) can be determined. For systems predominately based on a voltage independent charge photo-generation this analysis successfully allows to reconstruct the measured I/V response. Devices based on the promising copolymer PTB7 blended with PC71BM are used to study the influence of morphology on the recombination dynamics and thus the I/V characteristics. Furthermore we applied macroscopic device simulations to analyse the influence of the spatial distribution of charges in the active layer which can not be accounted for in the experiment.