An investigation of super-hydrophilic properties of TiO2/SnO2 nano composite thin films

A sol–gel dip coating technique was used to fabricate TiO2/SnO2 nano composite thin films on soda-lime glass. The solutions of SnO2 and TiO2 were mixed with different molar ratios of SnO2:TiO2 as 0, 3, 4, 6, 8, 9, 10.5, 13, 15, 19.5, 25 and 28 mol.% then the films were prepared by dip coating of the glasses. The effects of SnO2 concentration, number of coating cycles and annealing temperature on the hydrophilicity of films were studied using contact angle measurement. The films were characterized by means of scanning electron microscopy, X-ray diffraction and atomic force microscopy measurements. The nano composite thin films fabricated with 8 mol.% of SnO2, four dip coating cycles and annealing temperature of 500 °C showed super-hydrophilicity.