CeNS Colloquium

Prof. Peter Müller-Buschbaum
TU München

The investigation of nanostructures at surfaces, interfaces and in thin films requires dedicatedanalytical techniques, which provide information from a molecular to a mesoscopic scale. Inparticular, it is challenging to detect the complex morphologies which are necessary to havehigh efficiency organic solar cells. In such solar cells the active layer is sandwiched betweenmultiple other layers, the devices make use of a thin-film geometry and structures need to bedetected from the crystalline arrangement of the molecules to mesoscopic domain sizes. Theadvanced scattering techniques grazing incidence small and wide angle x-ray scattering(GISAXS and GIWAXS) allow for a determination of such structures [1-4]. The use ofdifferent scattering geometries including micro-focused x-ray beams as well as noveltechniques such as grazing incidence resonant soft X-ray scattering (GI-RSoXS) usingdifferent X-ray energies are applied to investigate organic solar cells. Examples based onconducting photoactive polymers and hybrid nanostructures are presented [5,6].

References
[1] P.Müller-Buschbaum: Grazing incidence small-angle x-ray scattering - an advancedscattering technique for the investigation of nanostructured polymer films; Anal. Bioanal.Chem. 376, 3 (2003).
[2] P. Müller-Buschbaum: Structure determination in the thin film geometry using grazingincidence small angle scattering; in "Polymer Surfaces and Interfaces: Characterization,Modification and Applications", edt. M. Stamm, p.17-46 Springer Berlin, ISBN-13: 978-3-540-73864-0 (2008).
[3] P. Müller-Buschbaum: A basic introduction to grazing incidence small angle X-rayscattering; in Special issue of Lecture Notes in Physics on "Applications of Synchrotron Lightto Noncrystalline Diffraction in Materials and Life Sciences", Vol. 776, edt. Ezquerra, T.A.;Garcia-Gutierrez, M.; Nogales, A.; Gomez, M.; p.61-90 Springer Berlin, ISBN-13: 978-3-540-95967-0 (2009).
[4] P.Müller-Buschbaum, V.Körstgens: Scanning probe microscopy and grazing incidencesmall-angle scattering as complementary tools for the investigation of polymer films andsurfaces; in Special issue of NanoScience and Technology on "Scanning Probe Microscopy inNanoscience and Nanotechnology 2", edt. Bhushan, B.; p.101-129 Springer Berlin, ISBN-13:978-3-642-10496-1 (2011).
[5] M.A.Ruderer, P.Müller-Buschbaum: Morphology of polymer-based bulk heterojunctionfilms for oganic photovoltaics (review); Soft Matter 7, 5482-5493 (2011).
[6] M.Rawolle, M.A.Niedermeier, G.Kaune, J.Perlich, P.Lellig, M.Memesa, Y.-J.Cheng,J.S.Gutmann, P.Müller-Buschbaum: Fabrication and characterization of nanostructuredtitania films with integrated function from inorganic-organic hybrid materials (review);Chem. Soc. Rev. 41, 5131-5142 (2012).