Dresden 2017 – wissenschaftliches Programm
CPP 21: Organic Electronics and Photovoltaics III: Mobile and Trapped Charges (joint session CPP/DS/HL, organized by CPP)
CPP 21.12: Vortrag
Dienstag, 21. März 2017, 12:30–12:45, ZEU 260
Tuning the Electronic Properties of 3D Covalent Organic Networks by Collective Electrostatic Design — •Veronika Obersteiner, Andreas Jeindl, Johannes Götz, Aurelie Perveaux, and Egbert Zojer — Institute of Solid State Physics, NAWI Graz, Graz University of Technology, Austria
Covalent organic frameworks have recently attracted substantial interest as materials for photovoltaics applications, as they can be synthesized mimicking donor-acceptor bulk heterojunctions.
On the basis of first-principle results we propose a novel design strategy for analogous 3D organic networks, where a band offset between different semiconducting segments can be achieved by introducing periodic arrangements of dipolar elements into the material. Exploiting the resulting collective electrostatic effects, we are able to manipulate the electronic landscape of the 3D networks in a controlled way,thereby, achieving spatially confined pathways for electrons and holes. The distinct advantage of this approach over conventional strategies for achieving the band offset by using chemically distinct donor and acceptor units is that the magnitude of the band offset can be tuned continuously. The suggested electrostatic design strategy also enables the realization of more complex structures like quantum-cascades and 'quantum-checkerboards'.