Preparation And Photocatalytic Properties Of Electrospun TiO₂,TiO₂/La₂O₃ Nanofibers

Through sol-gel processing and electrospinning technique, thin fibers of polyvinyl pyrrolidone(PVP)/titanium butyloxide composite fibers were prepared. After calcination of the above precursor fibers at 500℃,the titanium dioxide(TiO2) nanofibers were successfully obtained.The fibers were characterized by fourier transform infrared (FT-IR)spectroscopy, Raman spectroscopy, X-ray diffraction(XRD), scanning electron microscopy (SEM), and its photocatalytic properties were examined by degradation of methylene blue(MB) under UV radiation. The results showed that the anatase-type TiO2 was formed at 500℃and transformed to rutile at 600℃. The maximum photocatalytic decomposition rate was achieved with a calcination temperature at 500℃, the result was due to its anatase composition,small particle size and large special surface area, As the calcinations temperature increased to 600℃and 700℃, the photoactivity decreased, attributed to the formation of the rutile phase, and the change of the particle size and the special surface area also had some effects on this process. Moreover, the sample is easy to be reclaimed and considerable high photocatalytic efficiency can be obtained.Through sol-gel processing and electrospinning technique, thin fibers of polyvinyl pyrrolidone(PVP)/titanium butyloxide composite fibers were prepared. After calcination of the above precursor fibers at 500℃,the TiO2/La2O3nanofibers were successfully obtained. The fibers were characterized by fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, X-ray diffraction(XRD), scanning electron microscopy (SEM), and its photocatalytic properties were examined by degradation of methylene blue(MB) under visible light. The result indicated that the fiber we obtained at the calcination temperature of 500℃was amorphous. Gradually, anatase of TiO2 was formed When the temperature increased to 700℃,As the temperature to 800℃, rutile phase began to form. Compared to the pure TiO2 nano-fibers, La dopant had a great inhibition on TiO2 crystalline temperature and phase transformation,the particle size was smaller. The XPS result showed that La existed in the fiber with the form of La2O3.The high photocatalytic efficiency can be obtained when the calcination temperature was 700℃and the La contained was 2 mol%.