Fabrication of TiO2/SiO2 hybrid fibers with tunable internal porous structures

TiO2 nanoparticles are easily aggregated, which greatly hinders their application to be utilized as photocatalysts. One of the effective routes is to make the TiO2 nanoparticles assembled on/in a solid carrier. In current work we report the fabrication of hybrid TiO2/SiO2 fibers with tunable internal porous structures via a capillary electrospinning technique combined with subsequent high-temperature pyrolysis treatment, in which the porous SiO2 fiber frameworks could offer a platform to assemble the TiO2 nanoparticles with a uniform spatial distribution. The resultant fibers were systematically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). It is found that the introduced concentration of tetrabutyl titanate (TBOT) plays a profound effect on the formation of the hybrid TiO2/SiO2 fibers. The experimental results suggest that tailoring the concentrations of raw material in the precursor solutions could permit the formation of internal structures with solid, hollow and hierarchically porous shapes, enabling the fabrication of hybrid TiO2/SiO2 fibers with tunable structures. Present work could provide a facile strategy for limiting the aggregation of TiO2 nanoparticles, which could give them a promising high photocatalysis performance.