Preparation of super-hydropbobic titanium oxide film by sol-gel on substrate of common filter paper

A rough TiO(2) film was fabricated by sol-gel technique, the film exhibits perfect super-hydrophobicity with a contact angle of 150A degrees and glide angle of about 5A degrees after being modified with octyltrimethoxysilane. The super-hydrophobicity was converted to super-hydrophilicity by the irradiation of ultraviolet light for 20 h, the irradiated super-hydrophilic film evolves to be hydrophobic with a contact angle of about 120A degrees on the condition of being placed in dark for 2 weeks. Finally the property of super-hydrophobicity of TiO(2) film modified with octyltrimethoxysilane was discussed on the basis of Cassie's theory.