Effect of applied voltage to the characteristic of TiO2 nanofibers fabricated using electrospinning technique

Abstract

Titanium dioxide (TiO2) is an attractive semiconductor oxide compound due to its good stability properties both in chemical and photochemical. TiO2 in the form of nanofibers offers many advantages such as high surface area, flexibility of structures and mechanical properties such as stiffness and tensile strength. In this study, we reported the synthesis of TiO2 nanofibers using electrospinning technique. TiO2 nanofibers were produced from titanium (IV) iso-propoxide precursor solution at different applied voltages of 10 kV and 12 kV, while the flowrate was kept constant at 0.7 ml/hours during the process. The electrospinning process produced a thin layer of nanofibers which was then calcined for 1 hour at different calcination temperature. Based on the SEM images, we found that at applied voltage of 12 kV uniform and continuous nanofibers had already formed with the average diameter of nanofibers was in the order of sub microns. The diffraction pattern of TiO2 nanofibers shows that at a calcination temperature of 450°C, the phase was dominated by the anatase phase, while at 500°C it has a combination of anatase and rutile phases. Based on UV-Vis spectroscopy, it was found that the energy gap of TiO2 nanofibers calcined at temperature of 450°C and 500°C were 3.32 eV and 3.22 eV, respectively.