Differential Resistance Analysis of Charge Carrier Losses in Organic Bulk Heterojunction Solar Cells: Observing the Transition from Bimolecular to Trap‐Assisted Recombination and Quantifying the Order of Recombination

Differential resistance analysis has been shown to be effective at studying the charge carrier losses in bulk heterojunction solar cells. The variations of differential resistance with light intensity and Voc provide strong evidence for the identification of the recombination kinetics, revealing bimolecular as the dominating recombination mechanism in PCDTBT:PC60BM system and showing an evolution to trap-assisted recombination in presence of PC84BM trap states.