PH deeds on structural, optical, electrical and gas sensing performance of TiO2 nanofilms by automated nebulizer spray pyrolysis technique

Abstract

In this present study, TiO2 nanofilms were deposited at 773K by using titanium tetra isopropoxide as precursor and ethanol as solvent with the variation of pH for x=2.50, 6.50, and 10.50 through automated nebulizer spray pyrolysis (ANSP) technique. The properties of Structural (XRD), Topography (AFM) and surface morphology (FESEM) of the film shows the average particle size, average roughness and particle shape were drastically changed with respect to electrolyte pH parameter. Anatase phase of polycrystalline tetragonal structure was revealed by structural (XRD) and X-ray photoelectron study (XPS). The XPS study confirms the films that not detected with the other trace of impurity except carbon. The optical transmittance decreased at higher pH and their band gap energy in the range of 3.29–3.43eV was obtained with the change in electrolyte pH parameter for all the TiO2 film. The electrical study of dielectric constant, tan δ is continue to decrease with increase the frequency and the maximum dielectric constant and tan δ value observed as ∼41.73 and ∼03.62 for pH=6.50. The adsorption and desorption of various gas sensing performance of TiO2 film were analysed with the function of temperature and the high sensing response of NH3 where noted.