Abstract
Performance of poly(3-hexylthiophene):[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PC61BM) bulk-heterojuction organic photovoltaics was improved by incorporationg a small portion of an additive, 3-fluoro-4-cyanophenol (FCP). The addition of 5wt% FCP to the P3HT:PC61BM blend film resulted in an improvement of all parameters such as short circuit current, open circuit voltage and fill factor without even post-thermal annealing, and hence increased the overall power conversion efficiency by over 80% compared to that of reference cell without FCP. Optical measurement revealed that FCP additive in the P3HT:PC61BM blend film facilitates the crystallization (ordering) of P3HT chains, leading to increasing the exciton generation and charge transport efficiency.
Funding
This work was supported by research grants from the Catholic University of Daegu in 2013.