AUTHOR=Gasparini Nicola , García-Rodríguez Amaranda , Prosa Mario , Bayseç Şebnem , Palma-Cando Alex , Katsouras Athanasios , Avgeropoulos Apostolos , Pagona Georgia , Gregoriou Vasilis G. , Chochos Christos L. , Allard Sybille , Scherf Ulrich , Brabec Christoph J. , Ameri Tayebeh TITLE=Indacenodithienothiophene-Based Ternary Organic Solar Cells JOURNAL=Frontiers in Energy Research VOLUME=Volume 4 - 2016 YEAR=2017 URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2016.00040 DOI=10.3389/fenrg.2016.00040 ISSN=2296-598X ABSTRACT=One of the key aspects to achieve high efficiency in ternary BHJ solar cells is the physical and chemical compatibility between the donor materials. Here, we report the synthesis of a novel conjugated polymer (P1) containing alternating pyridyl[2,1,3]thiadiazole (PT) between two different donor fragments, dithienosilole (DTS) and indacenodithienothiophene (IDTT), used as a sensitizer in a host system of indacenodithieno[3,2-b]thiophene,2,3-bis(3-(octyloxy)phenyl)quinoxaline (PIDTTQ) and [6,6]-phenyl C70 butyric acid methyl ester (PC71BM). We found that the use of the same IDTT unit in the host and guest materials, does not lead to significant changes in the morphology of the ternary blend compared to the host binary. With the complementary use of optoelectronic characterizations, we found that the ternary cells suffer from a lower mobility-lifetime () product, adversely impacting the FF. However, the significant light harvesting in the NIR region improvement, compensating the transport losses, results in an overall power conversion efficiency enhancement of ~7% for ternary blends as compared to the PIDTTQ:PC71BM devices.