Dielectric and non-ohmic properties of CaCu3Ti4O12 polycrystalline devices by dielectric and impedance spectroscopy

• Grant number: 07/02843-4
• Support Opportunities: Regular Research Grants
• Start date: November 01, 2007
• End date: October 31, 2009
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Paulo Roberto Bueno
• Grantee: Paulo Roberto Bueno
• Host Institution: Instituto de Química (IQ). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

The main goal of this project is to study the giant dielectric properties (about 105) of CaCu3Ti4O12 polycrystalline systems by frequency response techniques, i.e. dielectric and impedance spectroscopy. CaCu3Ti4O12 devices present also non-ohmic properties whose origin is still not totally understood. By means of the use of the mentioned frequency response techniques it will be possible to enlighten the origin of these properties, as well as the origin of dielectric properties. It will be also studied the possible correlation between both properties, likely due to the existence of space charge region. The separation of the different process involved with these properties can be better performed by using frequency response techniques at different temperatures.Therefore, to achieve the main objective of the project, it will be developed a frequency response experimental setup capable of deal with frequency response measurements at different temperatures, i.e. high and low temperatures. (AU)