Fabrication, Characterization And Photocatalytic Activity Of TiO₂ Nanofiber Doped Rare Earths

Titanium dioxide exhibits unique photo-functionalities that make it an excellentchoice for photocatalytic applications in environmental protection, hydrogenproduction and energy fields due to TiO2 is a highly effective, saving energy, withoutany further polluted and low cost photocatalyst. So, the current issueis how to improve its efficiency under sunlight irradiation by structure modification.The details and results of the studing as following:(1)PVP/Ti(OiPr)4 nanofibers was prepared by electrospinning with sol in this chapter. It researched the influence that precursor heat treatment temperature had to growth and structure of TiO2 nanofibers and it characterizated samples by TG-DTA, XRD, FE-SEM, FT-IR and visible photocatalytic degradating methylene blue solution. The fiber diameter got thinner when the heat treatment temperature was 500℃. The structure was anatase. When the heat treatment temperature was 600℃, the fiber diameter got larger. The structure was changing from anatase to rutile. When the heat treatment temperature was 700℃, the fiber diameter got much larger. The structure was rutile. The effect of photocatalytic was the best when the heat treatment temperature was 500℃because the structure was anatase. The effect of photoatalytic got lower when the heat treatment temperature was 600℃and 700℃because the structure of TiO2 change from anatase to rutile. The visible catalytic experiment showed that catalytic performance of the fiber was the best when the calcinations temperature is 500℃.The degradation efficiency can get to 42.4% and the fiber has a best concentration which is 30mg/l.(2)PVP/Ti(OiPr)4/Gd(NO3)3,PVP/Ti(OiPr)4/Pr(NO3)3 nanofibers was prepared by electrospinning with sol in this chapter. It researched the influence that precursor heat treatment temperature had to growth and structure of TiO2 nanofibers and it characterizated samples by TG-DTA, XRD, FE-SEM, FT-IR and visible photocatalytic degradating methylene blue solution. The structure of TiO2 was anatase when the heat treatment temperature was 500℃. The structure of TiO2 was rutile when the heat treatment temperature was 700℃. TiO2 particles doped with gadolinium was smaller than pure TiO2 particles. It showed that the crystallization process of TiO2 was inhibited because of the doped gadolinium and the crystal conversion temperature of TiO2 was elevated obviously. So the catalytic properties was the best when calcinations temperature was 700℃and the catalytic properties of fiber was the best when the doped gadolinium was 2% as the visible catalytic experiment showed. The photocatalytic activity doped with gadolinium was better than it doped with praseodymium when the doping ratio were the same at the same temperature.