Buscaglia, Vincenzo

Carda, J. B.

G?mez, J. J.

Goyeneche, I.

Jovani, M. A.

Nanni, Paolo

Nu?ez, I.

Viviani, Massimo

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Toledo, Spain, 18-22 June, 2006                                                                                                351 / 373 
 
 
IEMC-O-03           Õ Back 
 
EFFECT OF Y AND Dy CO-DOPING ON ELECTRICAL CONDUCTIVITY OF CERIA CERAMICS 
S. KIYOKO TADOKORO, E.N.S. MUCCILLO 
Energy and Nuclear Research Institute – CCTM, Sao Paulo, Brazil. 
sktadokoro@click21.com.br 
 
 
The effect of co-joint additions of Y and Dy on electrical conductivity of ceria ceramics was studied by 
impedance spectroscopy measurements. Powder materials were synthesized by aqueous coprecipitation 
method to obtain Ce1-x (Y0.5Dy0.5)xOy with 0 < x < 0.15 . Sintering of powder compacts was carried out at 
1450 ºC for 4 h. The main results show that high densification (~ 95% of theoretical value) was attained 
for all compositions. Raman spectroscopy results evidenced the solid solution formation among cerium, 
yttrium and dysprosium. The electrical conductivity of sintered specimens varies with the total dopant 
content. A maximum conductivity value was obtained for a lower dopant content considering the 
behaviour of singly doped ceramics. Moreover, sintered specimens with the same total dopant content 
exhibit similar electrical conductivity values suggesting that the concentration of oxygen vacancies play a 
major role in the conduction process of co-doped ceramics. 
 
 
 
IEMC-O-04           Õ Back 
 
CORRELATION BETWEEN MICROSTRUCTURE AND ELECTRIC PROPERTIES IN SnO2 RICH ENAMELS 
I. NUÑEZ1, J.J. GÓMEZ2, I. GOYENECHE3, M.A. JOVANÍ3, J.B. CARDA1, M. VIVIANI4, V. BUSCAGLIA4, P. 
NANNI5 
1Departamento de Química Inorgánica y Orgánica, Universitat Jaume I de Castellón, Castellón, Spain. 
2Servei Central D’Instrumentació Científica, Universitat Jaume I de Castellón, Castellón, Spain. 
3Colorobbia España S.A, Villafames, Spain. 
4Institute for Energetics and Interphases, Italian National Research Council, Dept. Genoa, Genova, Italy. 
5Department of Chemical and Processing Engineering, University of Genoa, Genoa, Italy. 
carda@qio.uji.es 
 
 
Nowadays, electric properties of SnO2 are widely studied and known due to its applications as a gas 
sensor or as a film for transparent electrodes. Although stoichiometric SnO2 is an insulator it’s possible to 
increase its conductivity and make it a semiconductor when there is a deviation from stoichiometry by 
the presence of oxygen vacancies in its structure (SnO2-x)or by the introduction of other dopant agents 
In this work, SnO2 has been used as a fundamental part in the formulation and development of conductive 
ceramic enamels, increasing the stoichiometric deviation with the introduction of dopants as Sb(V). 
Moreover, the effect of the amount of dopants on the electrical properties and the effect of the enamel 
composition have been studied 
Synthesized enamels have been structural and microstructurally characterized and a study of their 
electrical properties has been carried out by impedance spectroscopy and the measurement of I-V 
characteristic. Therefore, electric properties have been related to the microstructure in the samples and 
activation energy of the different involved processes has been calculated. Finally a model for the system 
has been obtained where the different zones of composition and doping with a significant contribution in 
the electrical properties have been assigned. 
In order to separate the different contributions by impedance spectroscopy, high and low frequency 
measurements have been done in a range of temperature between 180 K and 480 K. In addition, due to 
the strong dependence of SnO2-x conductivity on oxygen vacancies, measurements al different O2 partial 
pressure have been carried out. 
 
 


Correlation between microstructure and electric properties in SnO(2) rich enamels

http://puma.isti.cnr.it/rmydownload.php?filename=cnr.ieni/cnr.ieni.ge/2006-A6-043/2006-A6-043.pdf

Correlation between microstructure and electric properties in SnO(2) rich enamels

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