PhD student in the group of Prof. Peter Müller-Buschbaum,
Research stay at the University of Oxford (for diploma thesis)
2009 - 2010
Diploma thesis in the group of Prof. Lukas Schmidt-Mende, LMU Munich
Topic of Diploma Thesis:
“Impact of Meso- and Nanostructure on Device Performance of Solid-State Dye-Sensitised Solar Cells”
2004 - 2010
Study of physics, LMU Munich
Scholarship of the IDK-NBT (Elite Network of Bavaria)
DAAD full scholar ship for a research visit at the University of Oxford
Precise control of the heterojunction morphology in thin films is one of the key issues for the improvement of organic photovoltaic (OPV) devices. Interdigitated interfaces of the organic material on the nanoscale provide ideal charge extraction pathways for separated charge carriers. Structured surfaces of the selective electrode on the lower microscale further allow for the enhancement of the optical absorption of the thin film components due to light trapping. Two different ways of artificial structuring are under investigation: Using hard templates as stamps nanostructured organic layers can be realized on ITO support. Precise control of the process facilitates the control of the template dimensions. Alternatively, a novel imprinting routine for polyethylenedioxy-thiophene:polystyrene-sulphonate (PEDOT:PSS) is studied as it is widely used as a selective intermediate electrode in OPVs blocking the electrons and collecting the holes. Thereby, master molds with nanoscale channels are used for the temperature and pressure assisted imprinting routine. The shape of the imprinted structures is easily tunable by the concentration of an additional plasticizer. Depending on the structure dimensions the device efficiency of OPVs can be increased this way. This improvement is addressed to additional optical diffraction at the PEDOT:PSS gratings leading to increased optical absorption due to light trapping.
J. Weickert, C. Palumbiny, M. Nedelcu, T. Bein, L. Schmidt-Mende:
"Controlled growth of TiO2 nanotubes on conducting glass"
Chem. Mater. 23 (2) (2011), 155-162
J. Weickert, H. Sun, C. Palumbiny, H. C. Hesse, L. Schmidt-Mende:
"Spray-deposited PEDOT:PSS for inverted organic solar cells"
Sol. Energ. Mat. Sol. Cells 94 2371 (2010)