INVESTIGADORES
CASTRO Miriam Susana
artículos
Título:
Impedance spectroscopy analysis of TiO2 thin film gas sensors obtained from water-based anatase colloids
Autor/es:
MIGUEL PONCE; RODRIGO PARRA; RALUCA SAVU; EDNAN JOANNI; PAULO BUENO; MARIO CILENSE; JOSÉ A. VARELA; MIRIAM CASTRO
Revista:
SENSORS AND ACTUATORS B-CHEMICAL
Editorial:
Elsevier Science
Referencias:
Año: 2009 vol. 139 p. 447 - 452
ISSN:
0925-4005
Resumen:
In this work impedance spectroscopy technique was employed in order to characterizethe gas sensing behavior of undoped titanium dioxide (TiO2) polycrystalline thin films. Theelectrical measurements were performed in a sensor testing chamber that allows independent control of temperature, pressure, gas composition and flow rate. Frequency measurements, in the range from 40Hz to 110MHz, were performed in order to evaluate the gas sensor response of the samples as a function of temperature (50-350ºC) and surrounding atmosphere (vacuum or air at atmospheric pressure). Impedance spectroscopy is a very useful and important technique due to the possibility of using this method for discriminating between grain boundary capacitance (Cgb) and grain boundary resistance (Rgb) contributions. Therefore, a simple model taking into account variations in the intergranular potential barriers is proposed in this work.
