Strontium Titanate Ceramics Obtained by Conventional and Microwave Methods

Abstract:

Thermoelectric materials are able to generate an electric potential when subjected to a temperature gradient. The efficiency of this conversion is based on the value of the figure of merit (ZT) of the material. One way to increase the value of ZT is producing nanostructured ceramics, because it should interfere in the thermal conductivity of the material. SrTiO₃ is also a thermoelectric oxide material, due it n-type semiconductor nature. In this study, ceramic powders were obtained by solid-state reaction, mixing stoichiometric amounts of titanium oxide (TiO₂) and strontium carbonate (SrCO₃) in a polypropylene jar with zirconium balls for three hours. This mixture was calcined at 1000°C for 2 hours. These samples were pressed into pellets with 12mm in diameter and were sintered under different conditions: by a conventional method in an resistive oven at 1400o C for 3 hours and in a microwave oven at temperatures of 1220°C 1350°C 1375°C 1400°C and 1450°C for thirty minutes. The powders were subjected to structural and ceramics were subjected to microstructural characterizations.

• Periodical: Materials Science Forum (Volumes 775-776)
• Pages: 445-449
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.775-776.445
• Online since: January 2014
• Authors: André Silva Chaves, Thalita Gonçalves Berti, Olívia de Andrade Raponi, Maria Virginia Gelfuso, Daniel Thomazini
• Keywords: Microwave, Semiconductor Ceramic, Strontium Titanate

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