Design and Fabrication of Nanostructure TiO2 Doped NiO as A Gas Sensor for NO2 Detection

Abstract

      In this paper, thin films of undoped and nickel oxide (NiO) doped titanium dioxide (TiO₂) were prepared using the chemical spray pyrolysis deposition (CSP) technique, with different concentrations of nickel oxide (NiO) in the range (3-9) wt%. The morphological, structural, electrical, and sensing properties of a gas of the prepared thin films were examined. XRD measurements showed that TiO₂ films have a polycrystalline structure. AFM analysis showed that these films have a regular structure both before and after doping . The roughness of these films  decreased after adding  impurities but then the opposite of that took  place. The electrical and gas sensing properties of titanium dioxide  was also affected after doping. The highest sensitivity value was obtained at doping concentration of 5wt% and working temperature 473ºK.