Influence of nanostructure on the device performance and charge recombination dynamics of P3HT:PCBM solar cells

Abstract

In this paper, we investigated the recombination dynamics of photogenerated charge carriers in a poly(3-hexylthiophene) (P3HT): [6,6]-phenyl-C 61 -butyric acid methyl ester (PC 61 BM) blend system with donor-acceptor ratio of 1 : 1 before and after solvent annealing treatment. The technique of transient photocurrent and photovoltage measurements were used, and charge carriers were photogenerated by a 7 ns laser pulse at room temperature (298 K). In transient photocurrent measurement, we observed some differences in the saturation extracted charge in P3HT:PCBM solar cells with different power efficiencies. In addition, the bimolecular recombination coefficient  is found to be 3.510