Regensburg 2007 – scientific programme
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CPP: Fachverband Chemische Physik und Polymerphysik
CPP 7: POSTER: INTERNAL SYMPOSIUM Scattering Experiments
CPP 7.26: Poster
Monday, March 26, 2007, 16:00–18:00, Poster B
GISAXS studies on titania ultrathin films with different morphologies — yajun cheng1, markus wolkenhauer1, gina bumbu1, stephan roth3, jochen gutmann1,2, and •yajun cheng1 — 1Max Planck Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany — 2Institute for Physical Chemistry, Johannes Gutenberg University, Welder Weg 11, D-55099 Mainz — 3HASYLAB at DESY, Notkestr. 85, D-22603 Hamburg
Ultrathin TiO2 films showing rich morphologies are achieved by using sol-gel chemistry coupled with an amphiphilic polystyrene-block-poly (ethylene oxide) (PS-b-PEO) diblock copolymer as a structure-directing agent. The block copolymer undergoes a good-poor-solvent pair induced phase separation in a mixed solution of 1,4-dioxane, concentrated hydrochloric acid (HCl) and Titanium tetraisopropoxide (TTIP). By adjusting the weight fractions of 1,4-dioxane, HCl, and TTIP, inorganic-block-copolymer composite films containing a variety of different morphologies are obtained. Through calcination the amorphous Titania composite films can be converted to crystalline anatase phase. Based on the local characterization of AFM and SEM on the various different morphologies of the film. Grazing incidence small angle x-ray scattering (GISAXS) is further conducted to study the lateral structure of the film over large length scale. As a complementary method, x-ray reflectivity experiment is made to investigate the electron density gradient normal to the substrate. As a result, the combination of local imaging characterization and average x-ray scattering experiment provide a deep insight into the structure of the film.