Controlled morphologies by molecular design and nano-embossing

• Applicants: Professor Dr. Klaus Müllen; Professor Dr. Peter Müller-Buschbaum; Professor Lukas Schmidt-Mende, Ph.D.
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2008 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 66024994

Up to now the efficiencies of organic solar cells cannot compete with conventional semiconductor photovoltaics. One major challenge is the control of the interfacial area between donor-acceptor materials. In this project, the synthesis and design of organic materials that phase separate spontaneously and a novel template deposition method on conducting glass substrates will enable supramolecular to nanometer scale ordering. Advanced scattering experiments such as grazing incidence wide- and small-angle X-ray scattering will give full details about the installed nanostructure. This full control and knowledge about the structure will allow us a systematic investigation of the dependence of device performance on the thin film morphology. The electrical properties of the active materials will be probed with high resolution scanning probe techniques such as Kelvin force microscopy and conductive scanning probe microscopy. Deeper understanding of the device physics and underlying optoelectronic processes in connection to the interface morphology will help to find the ideal organic solar cell structure.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1355: Elementary Processes of Organic Photovoltaics