CRC 951 I: HIOS - Adjusting energy levels of hybrid inorganic/organic heterostructures (Project A8)
This project will provide fundamental understanding of the energy levels at HIOS interfaces comprising ZnO and wide-gap conjugated molecules, mainly using photoelectron spectroscopy and the Kelvin probe method. Furthermore, we target developing means to adjust energy levels at a given inorganic/organic material pairing, in order to optimize either energy or charge transfer across the interface, using strong electron acceptor/donor molecules as interlayers between the two semiconducting materials and covalently bound arene-phosphonate monolayers.
Koch, Norbert Prof. Dr. techn. (Details) (Collaborative Research Centre 555 'Complex Non-linear Processes')
Financer
DFG Collaborative Research Centre
Duration of project
Start date: 07/2011
End date: 06/2015
Research Areas
Experimental Condensed Matter Physics
Research Areas
Experimentelle Physik, kondensierte Materie
Publications
S. Winkler, J. Frisch, R. Schlesinger, M. Oehzelt, R. Rieger, J. Räder, J. P. Rabe, K. Müllen, and
N. Koch, “Impact of molecular dipole moments on Fermi level pinning in thin films”,
J. Phys. Chem. C 118, 11731 (2014).
S. Winkler, J, Frisch, R. Schlesinger, M. Oehzelt, R. Rieger, J. Räder, J. P. Rabe, K. Müllen, and
N. Koch, “The impact of local work function variations on Fermi level pinning of organic semiconductors”,
J. Phys. Chem. C 117, 22285 (2013).
H. Wang, P. Amsalem, G. Heimel, I. Salzmann, N. Koch, and M. Oehzelt, “Band-bending in organic
semiconductors: the role of alkali-halide interlayers”, Adv. Mater. 26, 925 (2014).
M. Oehzelt, N. Koch, and G. Heimel, “Organic semiconductor density of states controls the energy
level alignment at electrode interfaces”, Nat. Commun. 5, 4174 (2014).
F. Bianchi, S. Sadofev, R. Schlesinger, B. Kobin, S. Hecht, N. Koch, F. Henneberger, and S. Blumstengel,
“Cascade energy transfer versus charge separation in ladder-type oligo(p-phenylene)/ZnO
hybrid structures for light-emitting applications”, Appl. Phys. Lett. 105, 233301 (2014).
M. Timpel, M. V. Nardi, S. Krause, G. Ligorio, C. Christodoulou, L. Pasquali, A. Giglia, J. Frisch,
B. Wegner, P. Moras, and N. Koch, “Surface modification of ZnO(0001)−Zn with phosphonate-based
self-assembled monolayers: Binding modes, orientation, and work function”, Chem. Mater. 26, 5042
(2014).
R. Schlesinger, Y. Xu, O. T. Hofmann, S. Winkler, J. Frisch, J. Niederhausen, A. Vollmer, S. Blumstengel,
F. Henneberger, P. Rinke, M. Scheffler, and N. Koch, “Controlling the work function of ZnO
and the energy-level alignment at the interface to organic semiconductors with a molecular electron
acceptor”, Phys. Rev. B. 87, 155311 (2013).
Y. Xu, O. T. Hofmann, R. Schlesinger, S. Winkler, J. Frisch, J. Niederhausen, A. Vollmer,
S. Blumstengel, F. Henneberger, N. Koch, P. Rinke, and M. Scheffler, “Space-charge transfer in
hybrid inorganic-organic systems”, Phys. Rev. Lett. 111, 226802 (2013).
H. Mendez, G. Heimel, A. Opitz, K. Sauer, P. Barkowski, M. Oehzelt, J. Soeda, T. Okamoto,
J. Takeya, J.-B. Arlin, J.-Y. Balandier, Y. Geerts, N. Koch, and I. Salzmann, “Doping of organic
semiconductors: Impact of dopant strength and electronic coupling”, Angew. Chem. 125, 7905 (2013).