Fabrication of photocatalytic PVA–TiO₂ nano-fibrous hybrid membrane using the electro-spinning method

Nano-fiber membranes hold great promise for use in filtration applications. In this study, a photocatalytic polyvinyl alcohol (PVA)/TiO₂ composite polymer membrane was successfully synthesized at different TiO₂ concentrations (20, 30, 40, and 50%) using the electro-spinning method. The parameters of electro-spinning including electrical field, tip-to-collector distance, and feed rate were optimized for fabrication process. The diameter of the electro-spun PVA–TiO₂ fibers and average size of the TiO₂ nano-particles loaded in the PVA nano-fibers ranged from 100 to 150 nm and 15 to 30 nm, respectively. X-ray diffraction analysis indicated that the main crystal structure was of the anatase type even though small rutile peaks were also observed for the PVA–TiO₂ membrane. TiO₂ nano-particles were embedded in the PVA fiber and were dispersed linearly along the fiber direction. As the amount of TiO₂ loaded in PVA increased, the tensile strength also increased while the tensile strain significantly decreased. Also, when the TiO₂ content was increased from 20 to 50%, the photocatalytic activity of the PVA–TiO₂ membranes increased.