Features of current transients of photogenerated charge carriers, extracted by linearly increased voltage

Dependencies of photogenerated charge carrier's extraction current by linearly increased voltage (photo-CELIV) on the light intensity, absorption coefficient and recombination rate were calculated numerically. The simple method for the determination of reduction factor of the Langevin recombination is presented. According to calculations, the time necessary to reach maximum of the CELIV current transient varies more than 10 times depending on parameters mentioned above. Thus, the latter can cause large errors in the estimation of charge carrier's mobility, which can be corrected using results of the numerical calculations. Numerically calculated photo-CELIV transients were compared with the experimentally obtained current transient in the blends of [6,6]-phenyl-C-61-butyric acid methyl ester (PCBM) with regioregular poly(3-hexylthiophene) (RR-P3HT), and PCBM with poly(2-methoxy-5-(3,7-dimethyloctyloxy)-para-phenylenevinylene) (MDMO-PPV). (C) 2012 Elsevier B.V. All rights reserved.