Humidity Sensing Elements Based on Zn-doped TiO2 Films Prepared via a Sol-gel Method

Abstract

Humidity sensing elements have been prepared via a sol-gel method on the basis of titanium n-butoxide, doped with ZnO. By this method Zn-modified titania films have been deposited on alumina substrates with interdigitated silver palladium electrodes and subsequent sintering at temperatures of 400°С and 800°С. Scanning electron microscopy has been employed to determine the surface morphology of the films obtained. Structural and compositional characterization has been done by X-ray diffraction analysis and energy dispersive X-ray spectroscopy. Electrical measurements of the characteristics and parameters of the obtained samples have been taken by an impedance analyzer within a frequency range from 100Hz to 1MHz. The impact of the Zn-dopant and sintering temperature on the samples electrical properties has been studied. The samples obtained by the sol-gel method described can be used as humidity sensing elements which change their resistance given changes in relative humidity at frequencies of up to about 1kHz.

DOI: http://dx.doi.org/10.5755/j01.ms.21.2.6244