Events
Special Seminar: Nadezda V. Tarakina, Characterisation of structural defects in layered compounds using transmission electron microscopy and X-ray diffraction
| Date: | Wednesday 21 May 2014 14:00 - 15:00 |
| Location: | The People’s Palace (PP2) |
The presence of defects in materials, such as dislocations, grain boundaries, stacking faults, twins, etc. is usually considered undesirable. However, such imperfections not always influence negatively on materials’ properties. A careful analysis of microstructural features can provide detailed insights into structure-property relationships, and even stimulate the engineering of defects on purpose. In this talk I will present two different cases where defects play opposite roles. First I will discuss Bi2Se3 topological-insulator thin films. The presence of structural defects in such films negatively affects their transport properties. Through a detailed microstructural characterisation using TEM and X-ray diffraction one can not only reveal the origin of different defects, but also propose a mechanism for suppressing them. Then I will address complex MO(OH)2 oxyhydroxides (M = Ti,Hf,Zr), which possess high concentrations of structural defects. The presence of defects not only positively influences the sorption properties of these compounds but generally also enhances their stability. I will show how the crystal structures of these compounds have been solved using mainly X-ray powder diffraction data.
Dr. Nadezda Tarakina
Institute of Physics
University of Würzburg
Am Hubland
D-97074 Würzburg
Germany
E-mail: nadezda.tarakina@physik.uni-wuerzburg.de
