Impedance spectroscopy study of TiO2 addition on the ceramic matrix Na2Nb4O11

• Published in: Journal of materials science. Materials in electronics 2013-12, Vol.24 (12), p.4993-4999
• Main Authors: Romeu, M. C., Oliveira, R. G. M., Sales, A. J. M., Silva, P. M. O., Filho, J. M. S., Costa, M. M., Sombra, A. S. B.
• Format: Article
• Language: English
• Subjects: Applied sciences; Characterization and Evaluation of Materials; Chemistry and Materials Science; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Dielectric properties of solids and liquids; Dielectrics, piezoelectrics, and ferroelectrics and their properties; Electronics; Exact sciences and technology; Materials; Materials Science; Optical and Electronic Materials; Permittivity (dielectric function); Physics
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-013-1514-6

In this paper a study of TiO 2 addition (0, 2, 5 and 10 wt%) and its effects in the impedance spectra of Na 2 Nb 4 O 11 ceramic matrix was carried out. The structural, dielectric properties of the addition in the Na 2 Nb 4 O 11 matrix were discussed. In the preliminary structural studies, X-ray diffractograms of the samples were recorded at room temperature with X-ray diffractometer with Cu-kα. The Rietveld refinement method was used and confirmed the monoclinic structure for pure sample. A study based on complex impedance spectroscopy was carried and the dielectric properties were obtained over a frequency range (100 Hz–1 MHz) in room temperature (300 K). In the dielectric analysis at 1 MHz was observed relative permittivity of 99.46 for pure sample and 84.37 to sample added with 5 wt% of TiO 2 , those samples showed losses 3.55 × 10 −2 and 9.22 × 10 −2 , respectively. In relation to relaxation phenomenon, Cole–Cole function was used for fitting pure and added samples data.