Solar Photocatalytic Oxidation of NO By Electronspun TiO2/ZnO Composite Nanofiber Mat for Enhancing Indoor Air Quality

Synthetic photocatalyst TiO₂ nanofibers prepared using a sol-gel assisted electrospinning method revealed higher activity than the commercial photocatalyst TiO₂, P25, in the photocatalytic oxidation (PCO) of NO. The inner nanopores structure of nanofibersas observed from the transmission electron microscopy (TEM) image was found to be the vital parameter for the increased activity of the photocatalyst. The TiO₂/ZnO composite nanofiber photocatalysthas lower band gap than TiO₂ nanofiber which favors photo-electron generation. It would have potentially higher photocatalytic efficiency if not for the fact that the introduction of ZnO might cause charge imbalance and formation of the unsaturated chemical bonds on the surface thus changing the surface oxygen vacancies of the catalyst responsible for generating the oxidation radicals. Photocatalytic efficiency was optimized by adding an appropriate amount of Zn (0.10 wt. %) to the TiO₂, and this percentage of Zn added to the composite was in accord with the X-ray photoelectron spectroscopy measurement.