Effect of Mixed-Phase TiO<sub>2</sub>/PVA Nanofibers on the Degradation on Methyl Orange
We report on the synthesis of nanostructured TiO 2 for various structural phases and observed the rate of degradation of methyl orange (MO) upon UV irradiation. Mixed phase nanocrystalline TiO 2 at temperature of 800°C shows higher rate of degradation of MO with the rate of 0.0203/min compared to other phases. This rate corresponds to the percentage of MO degradation of 58.85%, 71.69%, 86.25% and 91.82% for duration of 30, 60, 90 and 120 min of UV irradiations, respectively. The TiO 2 powder was prepared using titanium (IV) butoxide as the precursor via sol gel process. The samples were characterized using X-ray diffractometer (XRD) and field emission scanning electron microscopy (FESEM). The rate of degradation of MO after UV exposure was measured using UV-Vis spectrophotometer. The first order reaction rate constants ( k app ) of anatase; mixed-phase; and rutile phases were 0.0130, 0.0203 and 0.0029, respectively, which shows that mixed-phase TiO 2 has higher k app value indicating higher rate of degradation. The PVA/TiO 2 nanofibers were produced via electrospinning technique and similar tests on the nanofibers were conducted.Energy dispersive X-ray spectroscopy (EDX) indicates significant presence of TiO 2 is in nanofibers and the average diameter of the nanofibers was 600 nm.