Effect of [6,6]-phenyl C61-butyric acid methyl ester phase on the charge generation of poly(3-hexylthiophene)-based polymer solar cells

In this work, we have studied the effect of [6,6]-phenyl C61-butyric acid methyl ester (PC61BM) phase on the performance and charge photogeneration processes of poly (3-hexylthiophene) (P3HT) polymer solar cells (PSCs) using photoluminescence, electrochemical doping and transient absorption methods. The results show that the PC61BM phase facilitates the dissociation of photogenerated excitons and increases the charge photogeneration yield. The PC61BM phase blend in the active layer is able to increase the yield of the delocalized polarons (DP) in the P3HT donor phase using electrochemical doping methods. Furthermore, PC61BM phase facilitates the formation of bipolarons (BP) from polarons (P). These results aid in better understanding the charge photogeneration processes of PC61BM blended PSCs.