Influences of acids on morphology and properties of TiO2 grown on electrospun PVDF fibers

Abstract TiO 2 with different crystalline phases and morphologies was grown on poly(vinylidene fluoride) (PVDF) fibers through electrospinning followed by hydrothermal synthesis in different acidic environments. The structural and morphological characteristics of the as-prepared composites were studied. The results show that the type and the concentration of the acids have a decisive influence on the crystalline phase, morphology, and loading mass of the TiO 2 grown on the PVDF fiber. The formation of anatase TiO 2 is favored in the hydrothermal environment of H 2 SO 4 and CH 3 COOH, whereas rutile TiO 2 is more readily obtained in HCl and HNO 3 . The morphology and the mass of the grown TiO 2 undergo a significant change with increasing acid concentration. Four samples were selected from the TiO 2 /PVDF composites hydrothermally synthesized in H 2 SO 4 , HNO 3 , HCl, or CH 3 COOH to perform photocatalytic degradation of rhodamine B under 40 W UV lamp irradiation for 120 min. The TiO 2 /PVDF sample hydrothermally synthesized in H 2 SO 4 showed the highest photodegradation efficiency (about 63.2%) owing to its excellent optical performance, the highest TiO 2 loading mass, and the lowest photogenerated electron-hole recombination rate.