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Dielectric materials are essential components of electronic devices and electric power systems. Consequently, the design and development of new materials with enhanced dielectric response remain of great importance. This dissertation examines three different approaches to enhancing the dielectric response: (i) percolative composites, (ii) polymer blending, and (iii) the induction of …

Fabrication of electroceramics usually requires high sintering temperatures of 800 to 1400 °C, which can unintentionally lead to problems such as volatilization of species, formation of secondary phases and excessive grain growth. These problems can cause inhomogeneous microstructures, non-stoichiometric chemical compositions and limited material functionality. Therefore, there is a need …

Barium zirconate titanate-barium calcium titanate 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 (BZT-BCT) ceramic exhibits a high piezoelectric response in the vicinity of room temperature. It is an environment-friendly alternative to Pb(Zr1-xTix)O3 (PZT), the most used ceramic material in piezoelectric applications. Thin films meet the requirements related to the miniaturization of electronic components such as in …

In the scope of this thesis, I focused on SrTiO3 (ST)-based dielectric ceramic composites as a lead-free perovskite material, which holds great potential for use in various electronic components. Such materials are large-scale and fabricated under high energy requirements, indicating an increasing need for a more environmentally friendly processing method. …

Tin (IV) oxide, SnO2 (cassiterite), is an n-type semiconductor with an advantageous combination of chemical, electric and optical properties that make it suitable for a range of applications, from solid-state gas sensors, transparent conductive coatings, oxidation catalysts and varistors. In varistor ceramics, grain growth studies are of particular interest, because …

KTaO3 belongs to the group of incipient ferroelectrics, which are materials important from the fundamental, as well as from the applications, point of view. It is well known in its single-crystal form; however, the processing of technologically interesting ceramics and thin films is a challenging task and knowledge of their …

In this thesis we demonstrate a new, simple, and ecient method for the solid-state synthesis of oxides with a complex chemical composition. We modify the traditional solidstate synthesis method, which is used in the majority of ceramics laboratories around the world, in order to prepare multi-metallic oxide powders from classic …

This thesis describes an investigation of electrically conductive composites based on Si3N4 with dispersed TiN or ZrN particles fabricated by an in-situ composite method. The influence of the amount of conductive phase of the Si3N4/TiN and Si3N4/ZrN composites on the density, the flexural strength and the electrical conductivity were evaluated. …

The past fifteen years has seen the rapid development of various wireless communication devices, which operate at microwave or milimeterwave frequencies (mobile phones, wireless local-area networks (LAN), Bluetooth, etc.). At the same time, this progress has stimulated the development of new materials and process technologies, which enable the size reduction …

he thesis describes a study of aluminum nitride (AlN) powder hydrolysis in the temperature range between 5 °C and 90 °C. The analysis of the temperature dependence of the course of the hydrolysis and the reaction kinetics, along with a mechanistic model set up for the hydrolysis reactions, gives a …