GRK 2802: Dislocation-induced local symmetry reduction in single-crystal KNbO3 observed by Raman spectroscopy
Type of the data | Text | |
Type of the data | Dataset | |
Type of the data | Image | |
Type of the data | Model | |
Total size of the dataset | 103974035 | |
Author | Drechsler, Felix | |
Author | Himcinschi, Cameliu | |
Author | Preuß, Oliver | |
Author | Fang, Xufei | |
Author | Kortus, Jens | |
Upload date | 2026-01-12T15:27:29Z | |
Publication date | 2026-01-12T15:27:29Z | |
Publication date | 2026-01-12 | |
Abstract of the dataset | In recent years, dislocation-tuned functionalized ceramics have become one of the focal points of modern materials research due to their outstanding properties. These range from improved electrical conductivity and ferroelectric properties to dislocation-enhanced toughening and superconductivity, caused by local strain fields. The aim of this work is to investigate the dislocation-induced structural changes in single-crystal KNbO3 by micro-Raman spectroscopy. Dislocation-rich regions with tailored densities have been generated using the Brinell indenter scratching method. The influence of the dislocations on the single-crystal structure can be observed in the Raman spectra. The activation of additional Raman modes is observed, which does not occur in regions of low dislocation density. This observation is confirmed by DFT calculations of vibrational modes and is attributed to a reduction in the crystal symmetry due to increased defect densities in plastically deformed KNbO3. In addition, an increase in compressive stress at higher dislocation densities can be demonstrated by a blueshift in Raman mode positions. | |
Public reference to this page | https://opara.zih.tu-dresden.de/handle/123456789/1754 | |
Publisher | Technische Universität Bergakademie Freiberg | |
Specification of the discipline(s) | 3::32::307::307-01 | |
Specification of the discipline(s) | 3::32::307::307-02 | |
Title of the dataset | GRK 2802: Dislocation-induced local symmetry reduction in single-crystal KNbO3 observed by Raman spectroscopy | |
Project abstract | The aim of this doctoral research project is the comprehensive electrical characterization of inert, metal-ceramic anode materials for aluminum electrolysis in molten salt systems. A particular focus is placed on the temperature-dependent investigation of electrical conductivity. At the beginning of the project, a measurement setup for determining the specific electrical resistivity in the temperature range of 50 to 600 °C is available. This system, supervised by the Institute for Experimental Physics, will serve as a reference. In addition, temperature-dependent Raman spectroscopy will be used to analyze the phase composition of the composite electrodes and to identify newly formed phases that may result either from the fabrication process or from thermal and environmental influences encountered during operation in the electrolysis cell. Furthermore, electrical conductivity measurements will be performed within selected individual phases, with the goal of establishing a correlation between the structural and electrical properties of the materials. | |
Funding Acknowledgement | The dataset was generated within the framework of the Research Training Group GRK 2802 (project ID: 461482547) funded by the German Research Foundation (DFG). | |
Public project website(s) | www.tu-freiberg.de/en/research/grk2802 | |
Project title | GRK2802_P9II_Raman spectroscopic and electrical characterization of functionalized and recycle-based materials |