Thermal properties of electrospun polyvinylpyrrolidone/titanium tetraisopropoxide composite nanofibers

In this work, polyvinylpyrrolidone/titanium tetraisopropoxide (PVP/TTIP) composite nanofibers were prepared by electrospinning from alcoholic solutions. The morphology and the properties of the fibers were investigated by SEM, Raman spectroscopy, and XRD. The thermal properties and the evolved gases were studied in detail by TG/DTA-MS. The as-spun 800–900-nm-thick PVP/TTIP fibers were then, respectively, annealed in different atmospheres (air and nitrogen) and at different temperatures (550 °C, 900 °C) in order to obtain anatase and rutile TiO 2 nanofibers. The investigation of the thermal properties was important before the preparation of the oxide nanofibers, because based on them the crystallinity and the composition of the TiO 2 nanofibers could be controlled. Metal oxide nanofibers with a slightly smaller diameter, made up mostly by anatase TiO 2 , were successfully prepared when the annealing was done at 550 °C, while at 900 °C, rutile TiO 2 fibers were obtained. If nitrogen atmosphere was applied, the nanofibers contained some carbon residue as well.