Different amounts of a stable aqueous TiO₂ hydrosol were used to fabricate paper sheets having photocatalytic activity. The TiO₂ hydrosol was prepared in aqueous medium using titanium butoxide as precursor and acetic acid as catalyst for the hydrolysis of titanium butoxide. An aging process at room temperature and atmospheric pressure was finally applied to obtain crystalline anatase TiO₂ hydrosol. The effects of different TiO₂ hydrosol loadings on the mechanical strength and barrier properties of modified paper sheets were investigated in detail. The photocatalytic behavior of TiO₂-modified paper sheets was investigated as well using methylene blue (MB) as target pollutant.

A hydrophobic/oleophilic surface when immersed in water can result in an oleophilic or “Cassie” state of oil-wetting.