Influence of Various Alcoholic Solvents on Structural, Morphological and Compositional Properties of Sprayed TiO2 Films

摘要

Titanium oxide thin films were prepared using solutions of titanium (IV) isopropoxide, acetyl acetonate dissolved in various alcoholic solvents such as methanol, absolute ethanol, 1-butanol, 2-butanol, 1-propanol, 2-propanol and tbutanol in the volumetric ratio’s of 1:1.5:22.5 by spray pyrolysis technique at substrate temperature of 350ºC under optimum conditions. The films have uniform thickness varying from 0.8–0.9 µm and good adherence to the substrate. XRD studies show poly crystalline nature of films. The Crystallite size (D), microstrain (e) and dislocation density (d) values varied from 96–289 nm, 1.25–3.75 10-4 lin-2m-4 and 1.2–10.76 1013lin m-2 respectively. Increase of microstrain, dislocation density and anatase to anatse-rutile mixed phase change may be attributed to increase in the concentration of lattice imperfections, crystallization of amorphous TiO2 films and long carbon chains in alcohol solvents. Present investigation reveals that alcohols play an important role in the crystallization of TiO2 layers. SEM micrographs exhibit spherical, square, needle shaped grains and grain boundary formation. Comparative study of SEM micrographs indicates variation of grain size from 0.1–0.7 µm. EDAX analysis shows the formation of stoichiometric TiO2 films, with an O-to-Ti atomic ratio of near 2 and variation of ratio as a function of various a