Study Of High Activity ZnS Group And Ag₂O Semiconductor And Its Photocatalytic Activity

Energy shortages and environmental pollution have become the focus of world attention.As a kind of environment-friendly new technology,semiconductor photocatalytic technology has been paid more and more attention in environmental management,new energy development and organic synthesis.ZnS and Ag₂O are the hotspots of current semiconductor photocatalysis.We improve the photocatalytic performance of the material by broadening the light response range of the material with the narrow bandgap semiconductor composite and crystal face etching to promote the separation of photogenerated electrons and holes.In the first chapter,the research status of semiconductor photocatalyst and the basic principle of photocatalysis are introduced,and several methods of improving the photocatalytic activity of semiconductor are summarized.The basic properties of ZnS and Ag₂O semiconductors and their photocatalytic research status are summarized.This paper puts forward the basis of the topic and the main research work of the thesis.In the second chapter,broccoli-like ZnS microspheres were prepared by simple hydrothermal method.ZnS/Ag₂O composites were prepared by precipitation at room temperature using ZnS as template.The properties of the composites were characterized by a variety of test methods.The photocatalytic performance and stability of the composites were studied by degradation of methylene blue solution under xenon lamp irradiation.The free radical scavenging experiments were used to determine the active matter in the photocatalytic activity of the complex.And the possible mechanism of photocatalysis of ZnS/Ag₂O composite was proposed.In the third chapter,ZnS/CuS complex was prepared by hydrothermal method and precipitation method.ZnS/CuS complex showed strong photocatalytic activity than pure ZnS and CuS.Cyclic experiments showed that the stability of the complex was good.It is tentatively speculated that a possible complex photocatalytic mechanism.In the fourth chapter,ZnS microspheres precursor was prepared by hydrothermal method using PVP as crosslinking agent.ZnS/CdS complex was prepared by precursors and precipitation method.The photocatalytic hydrogen production of the complex was investigated.The ZnS/CdS complex exhibited good hydrogen production and stability.The mechanism of the photocatalytic performance of the composites was explored.In the fifth chapter,octahedral Ag₂O crystals were prepared by precipitation at room temperature.Ammonium oxalate was used as complexing agent to exert a specific effect on its morphology.And the Ag₂O crystal plane was etched with ammonia.The effects of the amount of ammonia on the Ag₂O crystal and the photocatalytic performance were investigated.In the sixth chapter,we summarize our main work.It briefly analyzes the innovation of this paper and describes the content that needs further inquiry.In this paper,the influence of the interaction between the composite semiconductors and the photocatalytic performance of the composite semiconductors is discussed mainly through the study of ZnS-based composite semiconductors and etching Ag₂O crystal planes,which is very important for the future development of semiconductor photocatalytic performance significance.