Photocatalytic treatment of acidic waste water by electrospun composite nanofibers of pH-sensitive hydrogel and TiO2

The composite nanofibers of poly(vinyl alcohol)/poly(N,N-dimethylaminopropyl acrylamide) hydrogel and TiO₂ were prepared by electrospinning for a novel treatment of acidic waste water. The anatase TiO₂ was used as a photocatalyst due to its high photodegradation efficiency. TiO₂ was immobilized in the electrospun fibers for an easy recovery of TiO₂ after the waste treatment. The hydrogel nanofibers swelled rapidly in the acidic condition due to the repulsion among the protonated amine groups in the polymer chains. High efficiency of photocatalytic decomposition of dye was obtained by the fast swelling of hydrogel in the acidic condition and the uniform dispersion of TiO₂ by sonication.