Philipp Ehrenreich

PhD student

E-Mail: Philipp.Ehrenreich@...

Phone: 5406

Room: P946


Research Interests

New applications as the development of flexible flat screens, organic transistors, and organic solar cells make polymer electronics a fast growing field of research. Furthermore, new technologies demand for properties that cannot be fulfilled by conventional semiconductors. In this context polymer materials, i.e. “plastic electronics”, offer many beneficial properties like high flexibility, low cost production, good recyclability, and an almost unlimited possibility to tune the semiconducting properties by chemical modification. Primarily responsible for these properties is a delocalized π-orbital system. Though it is well known that energetic and spatial disorder do not only influence charge-lattice interactions or exciton dynamics, many interesting questions are still not answered. In organic solar cells for instance, a combination of a donor type polymer with an acceptor material is necessary in order to overcome the relatively large exciton binding energy (Frenkel-exciton) for charge separation. This property (restriction?) is given for almost all organic semiconductors exhibiting a low permittivity. In a charge separation process, it is therefore important not only to understand the relevance of dipole interactions in the organic layer, but also the relevance of a delocalized wavefunction during the charge generation process.

The focus of my research is treating these fundamental question by using time resolved photoluminescence and ultrafast pump-probe techniques. With the help of those techniques it is possible to follow the dynamics from the very beginning of the exciton generation till the successful charge separation. By comparing polymer-polymer with polymer-inorganic interfaces, it is the aim to understand fundamental differences within the exciton separation processes.


Curriculum vitae

  • 1987 born in Stuttgart
  • 2011 Bachelor of Science, University of Konstanz
  • “Gettern mit HCl-Gas und Prozess-Simulationen”;  Fraunhofer Institut für Solare Energiesysteme, Freiburg;  Prof. Gerhard Willeke
  • 2013 Master of Science, Université Pierre et Marie Curie (Paris)
  • “Measurements of the electronic transport through single molecules”; Prof. Elke Scheer 
  • 2014 Master of Science, University of Konstanz
  • “Charge Generation in Hybrid Solar Cells”; Prof. Lukas Schmidt-Mende

Scholarship:

2013 DAAD-Stipendienprogramm PROMOS


Publications

P. Ehrenreich, S. Birkhold. E. Zimmermann, H.Hu, K.-D. Kim, J. Weickert, T. Pfadler, L. Schmidt-Mende, H-aggregate analysis of P3HT thin films-Capability and limitation of photoluminescence and UV/Vis spectroscopy, Scientific Reports, 6, 32434, (2016)

E. Zimmermann, K. K. Wong, M. Müller, H. Hu, P. Ehrenreich, M.Kohlstädt, U. Würfel, S. Mastroianni, G. Mathiazhagan, A. Hinsch, T. P. Gujar, M. Thelakkat, T. Pfadler, L. Schmidt-Mende, Characterization of perovskite solar cells: Towards a reliable measurement protocol, APL Mater. 4, 091901, (2016)

K. Luka-Guth, S. Hambsch, A. Bloch, P. Ehrenreich, B. Michael Briechle, F. Kilibarda, T. Sendler, D. Sysoiev, T. Huhn, A. Erbe, E. Scheer, Role of solvents in the electronic transport properties of single-molecule junctions, Beilstein J. Nanotechnol., 7, 1055–1067, (2016)

M. Gerigk, P. Ehrenreich, M. R. Wagner, I. Wimmer, J. S.n Reparaz, C. M. Sotomayor Torres, L. Schmidt-Mende, S. Polarz, Nanoparticle shape anisotropy and photoluminescence properties: Europium containing ZnO as a Model Case, Nanoscale, 7, 16969-16982, (2015) [doi]

A. Wisnet, K. Bader, S. B. Betzler, M. Handloser, P. Ehrenreich, T. Pfadler, J. Weickert, A. Hartschuh, L. Schmidt-Mende, C. Scheu, J. A. Dorman, Defeating loss mechanisms in 1D TiO2-based hybrid solar cells, Adv Funct Mater, 27,17, pages 2601-2608, (2015) [doi]

P. Ehrenreich, T. Pfadler, F. Paquin, L.-I. Dion-Bertrand, O. Pare-Labrosse, C. Silva, J. Weickert, L. Schmidt-Mende, Role of Charge Separation Mechanism and Local Disorder at Hybrid Solar Cell Interfaces, Phys Rev B 91, 035304 (2015) [doi]

T. Pfadler, M. Coric, C.M. Palumbiny, A.C. Jakowetz, K.-P. Strunk, J.A. Dorman, P. Ehrenreich, C. Wang, A. Hexemer, R.-Q. Png, P.K.H. Ho, P. Müller-Buschbaum, J. Weickert, L. Schmidt-Mende, Influence of Interfacial Area on Exciton Separation and Polaron Recombination in Nanostructured Bi-Layer All-Polymer Solar Cells, ACS Nano, 8 (12), 12397 (2014) [doi]

E. Zimmermann, P. Ehrenreich, T. Pfadler, J.A. Dorman, J. Weickert, L. Schmidt-Mende, Erroneous efficiency reports harm organic solar cell research, Nature Photon 8 669 (2014) [doi]

B.B. Briechle, Y. Kim, P. Ehrenreich, A. Erbe, D. Sysoiev, T. Huhn, U. Groth, E. Scheer, Current-voltage characteristics of single-molecule diarylethene junctions measured with adjustable golc electrodes in solution, Beilstein J Nanotechnol 3 798 (2012)

J. Hampel, P. Ehrenreich, N. Wiehl, J.V. Kratz, S. Reber, HCl gas gettering of low-cost silicon, Phys. Status Solidi A 210 (4) 767 (2012)