BiFeO3 ceramic matrix with Bi2O3 or PbO added: Mössbauer, Raman and dielectric spectroscopy studies
| Autor: | Antonio Sergio Bezerra Sombra, P. Alcantara, H. O. Rodrigues, Benilde F.O. Costa, A. J. M. Sales, P. M. O. Silva, G.F.M. Pires Junior, Sanclayton G. C. Moreira |
|---|---|
| Rok vydání: | 2011 |
| Předmět: |
Permittivity
Materials science Mössbauer spectroscopy Analytical chemistry Inorganic compounds Dielectric Atmospheric temperature range Ceramic matrix composite Condensed Matter Physics Dielectric spectroscopy Electronic Optical and Magnetic Materials Condensed Matter::Materials Science symbols.namesake Nuclear magnetic resonance Raman spectroscopy Electrical properties symbols Dielectric loss Electrical and Electronic Engineering Temperature coefficient |
| Zdroj: | Physica B: Condensed Matter. 406(13):2532-2539 |
| ISSN: | 0921-4526 |
| DOI: | 10.1016/j.physb.2011.03.050 |
| Popis: | In this paper Mossbauer, Raman and dielectric spectroscopy studies of BiFeO 3 (BFO) ceramic matrix with 3 or 10 wt% of Bi 2 O 3 or PbO added, obtained through a new procedure based on the solid-state method, are presented. Mossbauer spectroscopy shows the presence of a single magnetically ordered phase with a hyperfine magnetic field of 50 T. Raman spectra of BFO over the frequency range of 100–900 cm −1 have been investigated, at room temperature, under the excitation of 632.8 nm wavelength in order to evaluate the effect of additives on the structure of the ceramic matrix. Detailed studies of the dielectric properties of BiFeO 3 ceramic matrix like capacitance ( C ), dielectric permittivity ( e ) and dielectric loss (tan δ), were investigated in a wide frequency range (1 Hz–1 MHz), and in a temperature range (303–373 K). The complex impedance spectroscopy (CIS) technique, showed that these properties are strongly dependent on frequency, temperature and on the added level of impurity. The temperature coefficient of capacitance (TCC) of the samples was also evaluated. The study of the imaginary impedance (−Z″) and imaginary electric modulus ( M ″) as functions of frequency and temperature leads to the measurement of the activation energy ( E ac ), which is directly linked to the relaxation process associated with the interfacial polarization effect in these samples. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect