Leibniz Institute of Photonic Technology (IPHT), 07745 Jena, Germany
Supramolecular Control of Optical and Electronical Properties of Two-Dimensional Dye Layers
Supramolecular structures essen¬tially de¬ter¬mine photonic1 and elec¬tro¬nic ma¬terial properties.[1] To control supramolecular structures, we utilize interface assembly of amphiphilic dyes, essentially via the Langmuir-Blodgett (LB) technique, to yield well-de¬fined layers and their stacks with tailored optoelectronic properties. We demonstrate how different condensed phases can be accessed and how their intermolecular binding energies can be characterized via LB, respectively.[2] The LB as well as self-assembled monolayers are characterized optically via photothermal deflection spectroscopy[3] and electronically via square wave voltammetry[4]. Using the latter technique we were able to show that via supramolecular tuning the LUMO energy of fullerene films can be significantly shifted by 90 meV as compared to standard spin cast films (cf. 40 meV shift when changing from C60 to C70).[4] This LUMO energy shift was successfully translated to 70 mV variation in open circuit voltage of corresponding pi-Si-hybrid solar cells.[4]
References
[1] S. Das and M. Presselt, Journal of Materials Chemistry C 2019, 7, 6194-6216.
[2] a) 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; b) 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.
[3] M. L. Hupfer, F. Herrmann-Westendorf, M. Kaufmann, D. Weiss, R. Beckert, B. Dietzek and M. Presselt, Chemistry 2019, 25, 8630-8634.
[4] 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.
