Proceedings Article | 30 May 2022
KEYWORDS: Structural design, Interfaces, Solar energy, Structured photonic materials, Optoelectronics, Fullerenes, Control systems, Chemistry
Supramolecular structures essentially determine photonic and electronic material properties.1 To control supramolecular structures, we utilize interface assembly of amphiphilic dyes, essentially via the Langmuir-Blodgett (LB) technique, to yield well-defined layers and stacks with tailored optoelectronic properties. We demonstrate how different condensed phases can be accessed and how molecular orientations2 as well as intermolecular binding energies can be characterized directly at the interface via Langmuir isotherms and their hysteresis, respectively.3, 4 Using the latter techniques, free-standing, though being only covalently bound, bifacial dye membranes have been developed. For the example of amphiphilic fullerenes, we demonstrate a new continuously operating rolling Langmuir-Schaefer transfer of monolayers at varied packing densities, thus enabling a LUMO energy variation of the films by 70 meV as determined using square-wave-voltammetry. Such LUMO energy shifts could be transferred linearly to variation in open circuit voltage of corresponding pi-Si-hybrid solar cells.5
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3. M. L. Hupfer, M. Kaufmann, F. Herrmann-Westendorf, T. Sachse, L. Roussille, K. H. Feller, D. Weiss, V. Deckert, R. Beckert, B. Dietzek and M. Presselt, ACS Appl Mater Interfaces, 2017, 9, 44181-44191.
4. M. L. Hupfer, M. Kaufmann, S. May, J. Preiss, D. Weiss, B. Dietzek, R. Beckert and M. Presselt, Phys Chem Chem Phys, 2019, 21, 13241-13247.
5. S. Das, J. Preiß, J. Plentz, U. Brückner, M. von der Lühe, O. Eckardt, A. Dathe, F. H. Schacher, E. Täuscher, U. Ritter, A. Csáki, G. Andrä, B. Dietzek and M. Presselt, Advanced Energy Materials, 2018, 8, 1801737.