Characterization and optimization of electrospun TiO2/PVP nanofibers using Taguchi design of experiment method

TiO2 nanofibers were prepared within polyvinylpyrrolidone (PVP) polymer using a combination of sol–gel and electrospinning techniques. Based on a Taguchi design of experiment (DoE) method, the effects of sol–gel and electrospinning on the TiO2/PVP nanofibers’ diameter, including titanium isopropoxide (TiP) concentration, flow rate, needle tip-to-collector distance, and applied voltage were evaluated. The analysis of DoE experiments for nanofiber diameters demonstrated that TiP concentration was the most significant factor. An optimum combination to obtain smallest diameters was also determined with a minimum variation for electrospun TiO2/PVP nanofibers. The optimum combination was determined to be a 60% TiP concentration, at a flow rate of 1 ml/h, with the needle tip-to-collector distance at 11 cm (position a), and the applied voltage of 18 kV. This combination was further validated by conducting a confirmation experiment that used two different needles to study the effect of needle size. The average nanofiber diameter was approximately the same for both needle sizes in good accordance with the optimum condition estimated by the Taguchi DoE method.