| dc.description.abstract | In this study, we utilized electrospinning technique to fabricate anatase TiO2 nanofibers, by using a polymer solution or melt injecting from a small nozzle under the influence of high voltage electric field. We used the sol-gel method to synthesis the precursor which containing both poly(vinyl pyrrolidone) (PVP, Mw ≈ 1,300,000) and titanium isopropoxide in ethanol. When the liquid was injected through a needle under a strong electrical field, composite nanofibers made of PVP and amorphous TiO2 were formed as a result of electrostatic jetting. The polymer or residual solvent in these nanofibers could be subsequently removed and these nanofibers could convert into anatase phase via annealing in air at 450°C. In addition, we fabricated TiO2 nanofibers by using different parameters: PVP concentration, feeding rate, voltage, and collecting distance. We discussed how these parameters affected the morphology and the diameter of TiO2 nanofibers. By adding AgNO3 to our TiO2/PVP precursor, we could fabricate TiO2/Ag composite nanofibers. By using co-electrospinning method by adding mineral oil to TiO2/PVP precursor, we could fabricate hollow TiO2 nanotubes. By modifying the form of the collector to two parallel conducting electrodes, we could generate nanofibers as uniaxially aligned arrays.
Then titanium isopropoxide and cobalt acetate were dissolved in 2-methoxyethanol followed by adding PVP. Using above solution as the precursor for electrospinning, via different annealing temperature, we could obtain CoTiO3 nanofibers. The CoTiO3 nanofibers could be used in gas sensors and photocatalysts. | en_US |