Study On The Preparation Of Novel Photocatalytic Nanomaterials And Their Application In Photodegradation Of Environmental Pollutants

Semiconductor photocatalysis has received considerable attention since its potential application in energy and environmental fields. The sunlight utilization of traditional photocatalysts(such as TiO2, ZnO, ZnS) is very limited due to their wide band-gap. Thus, the development of novel visible light photocatalytst has become one of the hot spots in the field of photocatalysis, and the composite photocatalytst by coupling of two semiconductors is an effective method to realize this purpose.The purpose of this dissertation is the development of novel visible light photocatalytst, and thus prepares ZnS-In(OH)3-In2S3 composite photocatalyst, whose characters and application also have been explored in this paper. The main contains as follows:1. The effects of ZnS-In2S3-In(OH)3 photocatalytic activity with different amounts of ZnO nanosheets and thioacetamide(TAA) and hydrothermal temperature were explored.When the molar ratio of ZnO, TAA and In3+is 2: 3: 0.83, heated at120 °C for 6 h, the prepared sample has highest photocatalytic activity. Used of Xray diffraction and scanning electron microscopy to characterize the samples in different hydrothermal time, a possible mechanism was discussed.2. Five visible photocatalysts such as ZnS-In(OH)3-In2S3, ZnS-In2S3,ZnIn2S4-ZnS, In(OH)3-In2S3 and In2S3 were prepared.The products were characterized by many instruments. We compared and found a tremendous difference in the composition, microstructure and photodegradation activity of the products obtained using different raw materials and preparation procedures. In all of the samples, ZnS-In(OH)3-In2S3 is best in adsorption and photodegradation of RhB,thanks to its appropriate microstructure, energy band structure and the interaction between the components. And discuss the possible mechanism of the visible light induced photodegradation of RhB.3. The visible light-induced photodegradation of tri-substituted organotin with the composite ZnS-In(OH)3-In2S3 was studied. Using gas chromatography-massspectrometry,the photodegradation products were analyted, and found that it can not photocatalytic degradation of all tri-substituted organotin pollutants, tributyltin can only photocatalytic degradation that generate less toxic dibutyltin and inorganic tin,and discussed possible mechanism of the visible light induced photodegradation of tributyltin.