Natural super-hydrophilic porous TiO2/SiO2 composite thin film and preparation method thereof

The invention relates to a natural super-hydrophilic porous TiO2/SiO2 composite thin film and a preparation method thereof. The preparation method comprises the following steps of: adopting a sol-gel method and respectively taking tetrabutyl titanate and ethyl orthosilicate as precursors to prepare TiO2 sol and SiO2 sol; calculating according to the molar fraction, compounding through taking the addition quantity of the SiO2 sol as 1-50 percent of total contents of SiO2 and TiO2 to obtain TiO2/SiO2 composite sol; and coating the prepared composite sol on a substrate material, airing, calcining and cooling to obtain the super-hydrophilic thin film. The natural super-hydrophilic porous TiO2/SiO2 composite thin film and the preparation method thereof have the beneficial effects that the thin film prepared by the method has the double effects of phase separation-induced developed hole structure and SiO2 compounding, the aperture of the thin film is within the scope of 100 nm-6 mum, the thickness of the thin film is within the scope of 200 nm-20 mum, a contact angle of the surface of the thin film with water is below 5 degrees, and the self-cleaning, antifogging and antibacterial functions are optimal.