Effect of polymer concentration,needle diameter and annealing temperature on TiO2-PVP composite nanofibers synthesized by electrospinning technique

In this study, TiO₂-PVP nanofibers were successfully synthesized on an aluminium collector by using cost-effective electrospinning technique. The nanofibers were prepared at different polymer concentrations, needle diameters and annealing temperatures and properties were studied by various characterizations. The structural properties were studied by X-ray diffraction (XRD) and Raman spectroscopy techniques. Surface morphology and elemental analysis of the samples were investigated by scanning electron microscopy (SEM) attached with energy dispersive spectroscopy (EDS). The optical properties were carried out by UV–Visible absorption spectroscopy (UV–Vis). By varying the polymer concentration and needle diameter, the effect of viscosity and surface tension on the formation of TiO₂-PVP nanofibers was clearly observed by SEM micro images. EDS spectrum shows effective composition of pure TiO₂ nanofibers. XRD peaks observed at temperatures 500 °C, 700 °C and 900 °C confirmed the anatase, mixed and rutile phases of TiO₂ nanofibers respectively. Raman studies also confirmed these phases of TiO₂ nanofibers. The optical band-gap values calculated using Kubelka-Munk function lies in the range of 3.02–3.22 eV.