Preparation And Photocatalytic Activity Investigation Of Titanium Dioxide Nanomaterial

In modern society,water pollution has become the most focus problems which needs to be solved. Among all the chemical materials, titanium dioxide was regarded as one of the most promising materials to solve the global water pollution due to its unique properties, for instance, physical and chemical stability, non-toxicity and low-cost. However, low specific surface,high combination rate of photo-generated electron-hole pairs and complex separation process of titanium dioxide limited its practical applications. So we paied attention to prepare unique titanium dioxide nanomaterials including enlarge specific surface area and dope Ag into the titanium dioxide nanotubes, then studied their photocatalytic activities.The main content of this paper are as the following:(1) Titanium dioxide nanomaterials were synthsized by electrospinning method,the effect of different oil on morphologies of emulsion electrospun products has been systematically studied. High photocatalytic degradation performed titanium dioxide nanomaterials with diverse morphologies, including nanoparticles, nanofibers,necklace-like nanofibers, porous nanofibers and surface rough nanotubes were prepared based on different water/oil phase separation processes due to distinctive properties of oils. Our study in this work implied that we can prepare nanomaterials with diverse morphologies only by varying the types of oil added in precursors, which can be used to enlarge specific surface area. Compared with the pure titanium dioxide nanofibers, nearly of all the samples had the improved photocatalytic abilities.The precursor solution with mechanical pump oil added can prepare the surface rough nanotubes which has the largest specific surface area leading to the best photocatalytic properties, the degradation rate increased by 37.1%. Also, the circulating test was carried out to prove that all the samples here were in good stabilities and can be used in recycling.(2) Preparing nanostructure with large specific surface area can improve photocatalytic properties effectively, but it is still limited if we take step only by this one method. Combining with doping Ag into the titanium dioxide nanotubes and find the best ratio of doping amount, in order to improve separation of photo-generated electron-hole pairs, prolong the lifetime of charge carriers which can enhancephotocatalytic activities further. In this part, we firstly prepared titanium dioxide nanofibers with doping amount of Ag in 0.0%, 0.5%, 1.0%, 1.5%, 2.0% and 2.5%,found the best one in degredation experiment, then combined with the preparation method of nanotubes, synthsized the 1.5%-Ag/TiO2 nanotubes, that the degradation rate increased by 60.2% in the RhB degredation experiment.Our systematic study implied that emulsion electrospinning is a simple and feasible method to prepare nanomaterials with diverse morphologies. Combining with the noble metal Ag doped, it can enhance photocatalytic performance of TiO2 further.It is significative to be used in cleaning up the environment and fabricating other semiconductor-based nanomaterials.