Dresden 2017 – wissenschaftliches Programm
CPP 70.6: Vortrag
Freitag, 24. März 2017, 12:00–12:15, ZEU 255
Interfacial Energetics in Organic Multi-Heterojunctions by Charge-Transfer Emission — •Christian Kästner1, Koen Vandewal2, Daniel A. M. Egbe3, and Harald Hoppe4 — 1Institute of Thermodynamics and Fluid Mechanics, Technische Universität Ilmenau, Am Helmholtzring 1, 98693 Ilmenau, Germany — 2Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP), George-Bähr-Str. 1, 01069 Dresden, Germany — 3Linz Institute for Organic Solar Cells, Johannes Kepler University Linz, Altenbergerstr. 69, 4040 Linz, Austria — 4Center for Energy and Environmental Chemistry Jena (CEEC Jena), Friedrich Schiller University Jena, Philosphenweg 7a, 07743 Jena, Germany
Charge generation via exciton dissociation in organic solar cells requires donor-acceptor interfaces. Semi-crystalline phases of polymer and fullerene domains result in smaller energy gaps between the highest occupied molecular orbital and the lowest unoccupied molecular orbital as compared to the situation for amorphous phases. These molecular energy level shifts result in different interfacial charge transfer (CT) transitions depending on the disordered or ordered character of interfacing domains. In this work, a systematic variation of the order at the donor-acceptor interface was obtained via ternary blending of semi-crystalline and amorphous model polymers with a fullerene acceptor (PCBM). Using photo- and electroluminescence spectroscopy, various transition energies due to recombination across different donor-acceptor interfaces could be detected.