Study On Preparation And Photocatalysis Of Several New Kinds Of Photocatalysts

Chapter 1: The development of n-type and p-type photocatalysts was introduced in this chapter. The photodegradation mechanism and the methods for improving photocatalytic activity of titanium oxide photocatalyst such as transitional metal ion doping, compound semiconductor, precious metal surface deposition, surface sensitization, etc., were summarized. The aim of this chapter is to provide the help to develop high efficient, practical photocatalyst,and looking for the catalyst that can utilize sunlight directly is an important developing direction in the photocatalysis field. Visible light excitated catalyst is the focus in environment field too. The new improvement in recent years about catalyst's preparation,synthesize technology and catalysis mechanism are also summarized.Chapter 2: Cu2O particles was prepared by using NaBH4 as reducing agent, and the appearance and crystallographic form of the film were characterized by XRD and SEM. Degradation of methylene blue(MB) under irradiation of visible light with Cu2O was researched. The results indicated that the photocatalyst had high activity and the reaction mainly occurred on the surface of the catalyst. It approximately met the first-order kinetics. But photocatalysis of the catalyst was decreasing after reused several times. The XRD pattern indicated there were Cu(O) and Cu(II) on the surface of reused Cu2O particles. After washing by 0.1% HCl,the catalyst active come back.Chapter 3: The photocatalysis of BaPbO3 under visible light irradiation was studied. Some influencing factors,such as amount of catalyst used, density of p-chlorophenol, etc., were researched. The test showed that under the visible light irradiation, per 75% TOC of p-chlorophenol was decomposed by 0.15g BaPbO3 in solution containing 40ppm p-chlorophenol. After repeating five times, more than per 88% of p-chlorophenol could be decomposed by 0.2g BaPbO3. The photodegradation mechanism of the photocatalysis also was proposed.Chapter 4: BaBiO3 was used as a new kind of visible light response photocatalyst for the treatment of p-chlorophenol containing wastewater under visible light irradiation. Experimental variables, such as concentration of p-chlorophenol, pH of the solution,...