Impedance spectroscopy of SnO2: CoO during sintering
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Data
1997-01-01
Autores
Muccillo, R.
Cerri, J. A.
Leite, E. R.
Longo, Elson [UNESP]
Varela, José Arana [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Elsevier B.V.
Resumo
SnO2:m mol% CoO (0.5 less than or equal to m less than or equal to 6.0) ceramic specimens were studied by impedance spectroscopy in the 5 Hz-13 MHz frequency range during heating cold-pressed specimens from room temperature to 1250 degrees C. The electrical resistivity during sintering decreases from 4 to 6 orders of magnitude in the 400-1500 K temperature range depending on the amount of CoO. An increase in electrical resistivity in the 570-670 K range is related to the release of adsorbed water. The results for the 970-1500 K show that the higher the amount of the CoO addition, the lower is the temperature at which SnO2:CoO reaches a minimum electrical resistivity. This suggests that oxygen point defects created by dissolution of cobalt ions in the SnO2 lattice are controlling the densification rate of these ceramics.
Descrição
Palavras-chave
tin oxide, cobalt oxide dopant, resistivity, impedance spectroscopy, dilatometry, sintering aids
Como citar
Materials Letters. Amsterdam: Elsevier B.V., v. 30, n. 1, p. 125-130, 1997.