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

  • Zvezditza Nenova Technical University of Gabrovo
  • Toshko Nenov Technical University of Gabrovo
  • Stephan Kozhukharov University of Chemical Technology and Metallurgy
  • Maria Machkova University of Chemical Technology and Metallurgy
Keywords: humidity sensing elements, sol-gel method, titania, zinc dopant


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.


Author Biography

Zvezditza Nenova, Technical University of Gabrovo