A5062086326- Organic Electronics and Photovoltaics
- Organic Light-Emitting Diodes Research
- Molecular Junctions and Nanostructures
- Conducting polymers and applications
- Photochemistry and Electron Transfer Studies
- Luminescence and Fluorescent Materials
- Spectroscopy and Quantum Chemical Studies
- Photosynthetic Processes and Mechanisms
Heidelberg University
2017-2024
Kirchhoff (Germany)
2017-2018
Stable electrical doping of organic semiconductors is fundamental for the functionality high performance devices. It known that dopants can be subjected to strong diffusion in certain semiconductors. This work studies impact operating conditions on thin films polymer poly(3-hexylthiophene) (P3HT) and small molecule Spiro-MeOTAD, doped with two differently sized p-type dopants. The negatively charged drift upon application an electric field P3HT over surprisingly large distances. not observed...
Theoretical studies using clusters as model systems have been extremely successful in explaining various photophysical phenomena organic semiconductor (OSC) thin films. But they not able to satisfactorily simulate total and polarization-resolved absorption spectra of OSCs so far. In this work, we demonstrate that accurate are predicted by time-dependent density functional theory (TD-DFT) when the employed cluster reflects symmetry crystal structure all monomers feel same environment....
The diffusivity of dopants in semiconducting polymers is high interest as it enables methods sequential doping but also affects device stability. In this study, we investigate the diffusion a bulky sequentially deposited p-dopant poly(3-hexylthiophene) (P3HT) thin films using nondestructive situ infrared (IR) spectroscopy and photoelectron (PES). We probe dopant into polymer film at varying coverage by differentially evaluating electron transfer bulk surface. Thereby possible to determine...
Organic charge transfer complexes (CTCs) with near-infrared absorption received growing interest in the past years, but details of their photophysics, especially thin films, remain largely unknown. We combined experimental and computational methods to thoroughly investigate compare CTCs formed by tetracene 2,2′-(perfluoronaphthalene-2,6-diylidene)dimalononitrile 2,3,5,6-tetrafluoro-7,7,8,8,-tetracyanoquinodimethane, respectively. Using ultrafast transient spectroscopy, photophysics these...
Understanding the dynamics of excited states after optical excitation at donor-acceptor (D/A) interfaces is paramount importance for improving efficiency and performance optoelectronic devices. Here, we studied ultrafast state between electron donor (D) pentacene (PEN) acceptor (A) perfuoropentacene (PFP) as well within single compounds (PEN PFP) using femtosecond (fs) time-resolved second harmonic generation (SHG). In singlet fission observed on a time scale around 200 fs. bilayer systems...
The strong midinfrared polaronic signal in p‐doped polymers such as P3HT is analyzed terms of a plasmonic absorption cross section. Quantitative conclusion on the hole mobility along chains coherently connected thiophene units derived that way. This intrachain more than two orders magnitude higher average mobilities doped which limited by much less efficient interchain transport processes.