Proceedings of NFA-Based Organic Solar Cells: Materials, Morphology and Fundamentals (NFASC)
DOI: https://doi.org/10.29363/nanoge.nfasc.2021.015
Publication date: 25th January 2021
Efficient charge generation in organic semiconductors usually requires an interface with an energetic gradient between an electron donor and an electron acceptor in order to dissociate the photogenerated excitons. However, the necessity of this fundamental property is recently challenged as efficient single‐component organic solar cells were reported as well as solar cells based on binary and ternary systems providing charge separation despite the absence of a (large) energy gradient at the semiconductor interfaces. In this talk, I will discuss a few curious examples of NFA materials including homojunctions [1,2] and ternary blends, where photophysics is weakly influenced by band offsets of the components and is more sensitive to the film morphology and field‐assisted exciton dissociation mechanism.
[1] Nikolis, V. C., Dong, Y., Kublitski, J., Benduhn, J., Zheng, X., Huang, C., Yüzer, A. C., Ince, M., Spoltore, D., Durrant, J. R., Bakulin, A. A., Vandewal, K., Field Effect versus Driving Force: Charge Generation in Small‐Molecule Organic Solar Cells. Adv. Energy Mater. 2020, 10, 2002124 https://doi.org/10.1002/aenm.202002124
[2] Dong, Y., Nikolis, V.C., Talnack, F. et al. Orientation dependent molecular electrostatics drives efficient charge generation in homojunction organic solar cells. Nat Commun 11, 4617 (2020). https://doi.org/10.1038/s41467-020-18439-z