TY - JOUR
T1 - Electronic properties of SnO2-based ceramics with double function of varistor and Humidity sensor
AU - Glot, A. B.
AU - Sandoval-Garcia, A.P.
AU - Gaponov, A.V.
AU - Bulpett, R.
AU - Jones, B. J.
AU - Jimenez-Santana, G
PY - 2009
Y1 - 2009
N2 - Tin dioxide based varistor ceramics SnO2-Co3O4-Nb2O5-Cr2O3-xCuO (x=0; 0.05; 0.1 and 0.5) were made and their electrical properties were studied. The highest nonlinearity coefficient and electric field (at current density 10-3 A cm-2) were obtained for 0.1 mol.% CuO addition. It was observed that low-field electrical conductivity is increased with relative humidity, therefore, materials obtained exhibit double function of varistor and humidity sensor. The highest humidity sensitivity coefficient is found for SnO2-Co3O4-Nb2O5-Cr2O3 ceramics (without CuO). Observed varistor and humidity-sensitive properties are explained in the frames of grain-boundary double Schottky barrier concept as a decrease of the barrier height with electric field or relative humidity. Using suggested simple theory and data obtained on isothermal capacitance relaxation, the energy of the grain-boundary monoenergetic trapping states were estimated. These values are less than found for activation energy of electrical conduction (as a measure of the barrier height). These observations confirm the barrier concept.
AB - Tin dioxide based varistor ceramics SnO2-Co3O4-Nb2O5-Cr2O3-xCuO (x=0; 0.05; 0.1 and 0.5) were made and their electrical properties were studied. The highest nonlinearity coefficient and electric field (at current density 10-3 A cm-2) were obtained for 0.1 mol.% CuO addition. It was observed that low-field electrical conductivity is increased with relative humidity, therefore, materials obtained exhibit double function of varistor and humidity sensor. The highest humidity sensitivity coefficient is found for SnO2-Co3O4-Nb2O5-Cr2O3 ceramics (without CuO). Observed varistor and humidity-sensitive properties are explained in the frames of grain-boundary double Schottky barrier concept as a decrease of the barrier height with electric field or relative humidity. Using suggested simple theory and data obtained on isothermal capacitance relaxation, the energy of the grain-boundary monoenergetic trapping states were estimated. These values are less than found for activation energy of electrical conduction (as a measure of the barrier height). These observations confirm the barrier concept.
M3 - Article
VL - 10
SP - 21
EP - 32
JO - Advances in Technology of Materials and Materials Processing
JF - Advances in Technology of Materials and Materials Processing
SN - 1440-0731
ER -