Preparation And Application Of The TiO₂/polymer Hybrid Nanofibers

Electrospinning is a simple and low-cost technique for preparing ultrafine fibers. Within the last decade, significant progress was achieved on its theoretical and experimental studies. The diameter of electrospun fibers is usually 1-3 orders smaller than that of common fibers prepared by conventional spinning techniques. Thus, promising prospective was expected on the applications of the electrospun fibers in reinforced composites, filtration, biological materials, catalysis, sensor, energy sources, optical and electronic devices and so on. There were a lot of studies on electrospinning of polymer solution. Since sol-gel was introduced into electrospun, the scope of the electrospinning application had been broaded maximumly with a series of inorganic, inorganic/polymer electrospun nanofibers.In this study, tetra butyl titanate was used as precursor of TiO₂, and TiO₂/polymers hybrid nanofibers were prepared by electrospinning a blend solution of TBT and PAN or P(VdF-HFP). The TiO₂/polymers hybrid nanofibers were respectively applied to photocatalysis or lithium-ion batteries.1. The TiO₂/PVP hybrid nanofibers were prepared by electrospinning a blend of TBT and PVP. The TiO₂ (100³00 nm) nanofibers were achieved after the TiO₂/PVP hybrid nanofibers teated with solvent, then calcinated at 450℃in air. The crystal type of TiO₂ nanofibers was analysed by XRD. More than 80 percent of methyl blue was degraded by photocatalysis with this kind of TiO₂ nanfibers in 40 mg/L solution within 35 minutes.2. The TiO₂/PAN hybrid nanofibers were prepared by electrospinning a blend solution of TBT and PAN in DMF. The TiO₂/ pre-oxidized silk nanofibers were achieved after the TiO₂/PAN hybrid nanofibers calcinated at 450℃in nitrogen. Further more, this kind of pre-oxidized silk strengthens the tenacity of TiO₂ nanofibers and doesn't depress its photocatalytic performance.3. The P(VdF-HFP) polymer nanofibers was prepared by electrospinning a 13% P(VdF-HFP) copolymer solution in DMAc/ketone mixing solvent. A membrane of microporous gel polymer electrolytes (MGPE) was achieved after absorbing a LiPF6/EC-DMC-EMC electrolyte solution. The membrane shows that ionic conductivity of 1.47×10-3 s/cm and lithium ions transference number of 0.84 in simulated lithium ions cell at room temperature.4. The TiO₂/P(VdF-HFP) hybrid nanofibers membrane was prepared by electrospinning the P(VdF-HFP) copymer solution which added TBT. The electrochemistric performance of the MGPE, especially in low-temperature, was improved observably. By comparing composition and the morphologe of two MGPE, some influencing factors on ionic conductivity and lithium ions transference number was discussed.