The Preparation And Research Of Magnetically Separable TiO₂ Photocatalyst Nanofibers

Sr_1-xLa_xFe_12-xCo_xO₁₉(x=0⁰.5) ferrite nanofibers were successfully abtained by electrospinning technique. The samples, morphology, phases, structure and magnetic properties of the nanofibers were characterized by Scanning electron microscopy(SEM), Transmission electron microscope(TEM), X-ray diffraction(XRD) and Vibrating sample magnetometer(VSM). The results show that the samples have an uniform diameter of 80¹50 nm after being calcined at 800 oC. The substitution of La³⁺ and Co²⁺ obviously increases the magnetic properties of the as-prepared samples at x≤0.1, the coercivity(Hc) and remanent magnetization(Mr) of Sr0.9La0.1Fe11.9Co0.1O19 nanofiers correspondingly are 432.02 kA/m, 28.9 A·m2/kg, which were much enhanced compared to the Sr0.9La0.1Fe11.9Co0.1O19 powder sample.TiO₂/Mn₂O₃ nanofibers were abtained by electrospinning methods. The TiO₂/Mn₂O₃ nanofibers were characterized by SEM, TG-DTA, XRD and UV-Vis spectrophotometer. The results showed that it can be produced into TiO₂/Mn₂O₃ nanofibers with a small diameter of 100 nm after calcination at 500°C. The incorporation of Mn₂O₃ into titania dioxide can significantly extend the absorption by the photocatalysts into visible range.On the base of above research, magnetically separable photocatalysis materials, La³⁺-TiO₂/CoFe₂O₄ nanofibers and TiO₂/SrFe₁₂O₁₉ nanospheres, were obtained by means of a novel two-spinneret electrospinning technique and sol-gel method. The photocatalysis materials were characterized by XRD,SEM,TEM and VSM respectively. The results show that, the <1.0% La-doped TiO₂>/CoFe₂O₄ nanofibers have an efficient photocatalytic property, and the degradation rate of MB could reach 93% in 2.5 h. Moreover, the nanofibers show a good magnetic response. The average diameter of the TiO₂/SrFe₁₂O₁₉ nanospheres is 300-700 nm after calcination. and the photodegradation ratio of MB by TiO₂/SrFe₁₂O₁₉ nanospheres is up to 93% under irradiation for 2.5 h. The nanospheres has a large coercivity, indicating the possibility of those easy recycling property.