Synthesis Of Novel Titanium Dioxide Photocatalytic Materials And Their Photocatalytic Properties

With the development of industry,water pollution derived from organic contaminants has recently become a prominent problem to endanger human health,which eagerly needs to be solved.Photocatalysis technology,a new approach to solve water pollution,has attracted widespread interest in various disciplines.Among exciting semiconductor photocatalysts,TiO2 features not only the low cost,rich resource,and nontoxicity,but also the high photocatalytic activity and stability under the irradiation of UV-light,thus attracting tremendous research interest.However,commercial titanium dioxide,which is generally nanoparticle,has a low absorption and utilization rate of light and thus inhibits the catalytic activity.TiO2 sphere-in-sphere with surface nanosheet synthesized by hydrothermal method,is a spherical structure that enhances the absorption of light.On the other hand,after excited by ultraviolet light,the generated electron and hole tend to recombination.After combined with carbon nanotubes,the high carrier transport rate of TiO2/CNT composite can effectively promote the separation of electron and hole in TiO2.The main research contents of the thesis are as follows:First,we describe a facile temple-free solvothermal method to synthesize TiO2 sphere-in-sphere with nanosheet on its surface with the assistance of diethylenediamine(DETA).By adjusting the different crystallization time to explore its growth mechanism,found that the DETA plays the role if a linker,while promoting the growth of a single crystal plane.Meanwhile,the TiO2 solid sphere was synthesized under the same solvothermal conditions without the assistance of DETA.For comparison,the sample without the assistance of DETA was prepared to measure the photocatalytic activity for degradation of enrofloxacin hydrochloride,and found that the titanium dioxide sphere-in-sphere with surface nanosheet shows better catalytic performance than the titanium dioxide solid sphere.Second,a simple and facile solvothermal method is utilized to prepare TiO2 nanoparticles supported on CNT with the assistance of DETA.By tuning different precursor(isopropyl titanate,CNT,DETA),a group of TiO2/CNT composites have been separately obtained,and their adsorption capacity and photodegrading activity for MB removal were evaluated in detail.It is found that DETA greatly affect the loading uniformity and dispersity of TiO2 particles supported,and the TiO2/CNT composite with 0.02 mL DETA added shows a strong interaction and the rapid electron-transfer efficiency between TiO2 and CNT.Meanwhile,the catalyst shows both low adsorption capacity and good photocatalytic activity.