Effects of processing parameters on the synthesis of TiO2 nanofibers by electrospinning

TiO² nanofibers were synthesized by an electrospinning technique using polyvinyl pyrrolidone and titanium tetraisopropoxide as precursors. The effects of processing parameters including the precursor ratio, calcination time, temperature and atmosphere were investigated. The calcination temperature determines the TiO₂ phases as either anatase or rutile. The diameter of the synthesized TiO₂ nanofibers is not sensitive to the calcination atmosphere or the time. However, the surface microstructure of the synthesized nanofibers depends highly on calcination atmosphere. Calcination in an N₂ atmosphere produces smooth surfaces. In contrast, surfaces that are more granular evolve when they are calcined in an O₂ atmosphere. In addition, less Ti precursor in the electrospinning solution results in slim nanofibers.