Preparation,Modification Of Low-dimensional TiO₂ Nanomaterials And Their Catalytic Performance Study

With the yearly improvement of people's living standard, human's requirements for the environmental quality are increasing. However, With the development of social industrialization, a large amount of pollutants discharged into the natural environment caused the environmental contamination. It is serious damage to the human's living quality and affects people's physical and psychological health. What is more, the environmental issue hinders the pace of human's development. Therefore,environmental issue has become a urgent problem for modern society. In the last few years, semiconductor photocatalysis has entered people's life and attracted a comprehensive attention for its predominant performance on environmental purification. Photocatalytic degradation of organic matter in sewage pollution has become the most promising treatment dealing with the polluted water. Photocatalytic technology can oxidative decompose the organic matter of sewage into H2 O, CO₂ and non-hazardous organic acids. The widely-used semiconductor photocatalyst mainly concludes TiO₂, Cu O, Zn O, Fe2O3, Cd Se so far, among these semiconductor photocatalyst, titanium dioxide has obtained a profound study in the field of sewage treatment for its nontoxicity, recyclability and affordability. However, titanium dioxide has some disadvantages which limit its practical application, such as recombination of photo-generated electron-hole pairs, high band gap and low efficiency of quantum in photocatalytic activity. Therefore, several methods have been devoted to modify the surface of titanium dioxide to improve its photocatalysis efficiency in recent years. In this paper, we have fabricated TiO₂ nanofibers?TiO₂ NFs?and TiO₂ nanotubes?TiO₂ NTs? by electrospinning technique and anodic oxidation method. We modified the the titanium dioxide with Ag, Pb O₂ and polydopamine?PDA?. The main works of this paper can be summarized as follows:?i? Preparation of TiO₂ NFs by electrospinning method. In the the photocatalytic degradation experiment, methyl orange solution as the degraded products, coupling the ultrasonic field, electric field and thermal field into the UV field. The results indicated that multi-field coupling could promote the photocatalytic reaction. Through the conclusions of experiments, we prepared a multi-field coupling photocatalytic reactor, this reactor can be used for the treatment of industrial wastewater.?ii? we have fabricated PDA-Ag/TiO₂ NFs composite by electrospinning technique and impregnation method. This composite just like a porous substrate embedded by the Ag NPs and wrapped by the PDA that we called it corn-like structure. The results of the photodegradation of methyl orange by ultraviolet light show that the corn-like PDA–Ag/TiO₂ NFs composite catalyst exhibits high-efficiency photocatalytic activity compared to TiO₂ NFs.?iii? TiO₂ NTs have fabricated by the anodic oxidation of pure Ti sheets. The formation and growth of Pb O₂ inside the TiO₂ NTs was achieved using a electrochemical deposition method. Then, the PDA film was modified the surface of the TiO₂ NTs by impregnation method. Finally, we got the PDA-Pb O₂/TiO₂ NTs/Ti composite electrode which exhibits a special structure. Through the experiment of toluene degradation, the PDA-Pb O₂/TiO₂ NTs/Ti composite electrode showed excellent photoelectric performance.This photoelectric performance not only behaved under ultraviolet light, but also, the experiments show that the composite electrode still exhibits superior photoelectric performance under simulated sunlight irradiation.