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Properties of novel magnetoelectric and multiferroic ceramic materials
Osička, Luděk ; Kachlík, Martin (referee) ; Maca, Karel (advisor)
Literature search about properties of magnetoelectric and multiferroic ceramic materials was made. Ferromagnetism and ferroelectricity and requirements for materials in which both of these properties can exist in the same phase were discussed. Further, multiferroics were classified by mechanism of ferroelectricity and by their crystal structure. Finally, multiferroic and magnetoelectric composites and some examples of strong magnetoelectric effect in multiferroics were described. In experimental part of this bachelor thesis preparation of specimens of magnetoelectric perovskite EuTiO3 was described. Prepared specimens had higher density than specimens described in literature and were phase-pure and they are suitable for research of magnetoelectric properties of EuTiO3 by infrared spectroscopy.
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Processing and properties of novel magnetoelectric and multiferroic ceramic materials
Osička, Luděk ; Pouchlý, Václav (referee) ; Maca, Karel (advisor)
A literature review on the topic of ferroic and multiferroic solid solutions of BaTiO3, SrTiO3 and EuTiO3 forms the first part of this master thesis. The second part describes the experimental preparation and evaluation of the properties of samples of europium strontium titanates - EuxSr1-xTiO3. First, the high temperature solid state synthesis was carried out and relative density and open porosity of the sintered samples were evaluated. The sintered samples showed open porosity higher than 10%. The reasons for this behavior were evaluated and described from the point of view of experimental conditions and thermodynamical calculations. Finally, electric and dielectric properties of selected samples were measured. These results show that these samples are insulators and their residual conductivity is caused probably by oxygen vacancies, arising from the synthesis in a strongly reducing atmosphere of pure hydrogen.
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Processing and properties of novel magnetoelectric and multiferroic ceramic materials
Osička, Luděk ; Pouchlý, Václav (referee) ; Maca, Karel (advisor)
A literature review on the topic of ferroic and multiferroic solid solutions of BaTiO3, SrTiO3 and EuTiO3 forms the first part of this master thesis. The second part describes the experimental preparation and evaluation of the properties of samples of europium strontium titanates - EuxSr1-xTiO3. First, the high temperature solid state synthesis was carried out and relative density and open porosity of the sintered samples were evaluated. The sintered samples showed open porosity higher than 10%. The reasons for this behavior were evaluated and described from the point of view of experimental conditions and thermodynamical calculations. Finally, electric and dielectric properties of selected samples were measured. These results show that these samples are insulators and their residual conductivity is caused probably by oxygen vacancies, arising from the synthesis in a strongly reducing atmosphere of pure hydrogen.
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Properties of novel magnetoelectric and multiferroic ceramic materials
Osička, Luděk ; Kachlík, Martin (referee) ; Maca, Karel (advisor)
Literature search about properties of magnetoelectric and multiferroic ceramic materials was made. Ferromagnetism and ferroelectricity and requirements for materials in which both of these properties can exist in the same phase were discussed. Further, multiferroics were classified by mechanism of ferroelectricity and by their crystal structure. Finally, multiferroic and magnetoelectric composites and some examples of strong magnetoelectric effect in multiferroics were described. In experimental part of this bachelor thesis preparation of specimens of magnetoelectric perovskite EuTiO3 was described. Prepared specimens had higher density than specimens described in literature and were phase-pure and they are suitable for research of magnetoelectric properties of EuTiO3 by infrared spectroscopy.
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