Modification Of Tungsten Oxide Semiconductor Photocatalyst And Its Photoelectrocatalytic Properties

With the rapid development of industry,the discharge of a large number of toxic pollutants seriously endangers human health.Human beings need to attach great importance to the discharge,treatment and recycling of pollutants,thereby reducing the consumption of non-renewable resources and environmental pollution,which places demands on green and sustainable energy.Semiconductor photocatalytic technology has shown superiority in solving the energy shortage and environmental pollution faced by human beings.Among many semiconductor photocatalysts,tungsten oxide semiconductors have attracted wide attention due to their wide range of sunlight response and ease of synthesis.At the same time,China’s rich tungsten resources provide a rich source of tungsten oxide.However,due to its low quantum efficiency and high probability of photoexcited carrier recombination,its promotion and application in the field of photocatalysis is limited.The special structure and morphology of tungsten oxide can have a profound effect on the properties of the material.Therefore,many studies have been conducted on the phase,microstructure,and crystal growth of tungsten oxide.Based on previous studies,this paper further studied the effects of reaction conditions on the phase,microstructure and crystal growth of tungsten oxide,and explored the microscopic mechanism affecting the catalytic performance of tungsten oxide.On the one hand,the effects of different reaction temperatures on the growth of the phase and microstructure of the prepared product were investigated to investigate the effect of reaction temperature on product properties.On the other hand,the mechanism of the influence of the presence of crystal water on the catalytic performance of tungsten oxide during the synthesis of tungsten oxide was further explored,revealing the indispensable role of crystal water in the catalytic process of tungsten oxide.The effects of surface defects on the phase,microstructure and crystal growth of tungsten oxide were also investigated,and the mechanism of defects affecting catalytic performance was further explored.Provide experimental and theoretical guidance for the further development of semiconductor photocatalysts that study high-efficiency and high-light response ranges.The main research contents and scientific research achievements are as follows:The first chapter mainly introduces the research background and significance of this paper.The basic principles,research difficulties,existing problems and development status of semiconductor photocatalysts are briefly described.The advantages and disadvantages of WO₃ based photocatalysts and the commonly used modification methods are also illustrated.The performance mechanism affecting the catalysts is also listed in detail.At the end of the paper,I elaborated the topic of the topic and the main research contents.In the second chapter,the growth direction of WO₃ nanorods was controlled by adjusting the hydrothermal reaction temperature.The results showed that the growth direction of WO₃ changed from（200）,（110）to（111）as the reaction temperature increased.Photocatalytic performance Tests show that the photocatalyst grown in the（111）direction has the highest photocatalytic degradation dye activity,while the transition structure of the WO₃ catalyst has the lowest activity;combined with photoelectrochemical testing,we speculate that the photocatalyst grown in the（111）direction has excellent electrons-The hole separation ability is a major cause of an increase in photocatalytic performance.In the third chapter,tungsten oxide semiconductors with different surface structures are obtained by using different surface post-treatment methods.The results show that different surface microstructures have a significant effect on the photocatalytic performance of tungsten oxide.On this basis,the effects of different surface structures on the photoelectrochemical performance of WO₃ and its mechanism of action were explored,which laid the experimental foundation for the study of designing efficient photocatalysts.The fourth chapter focuses on the characteristics of crystallization water in WO₃.The main research goal of crystallization water is to control the gain and loss of WO₃ cry-stallization water by annealing and rehydration,and to explore the effect of crystallization water on the photoelectrochemical performance of WO₃ and its mechanism.Further explored the active species that affect the photocatalytic reaction before and after the loss of crystal water.The work of this chapter is of great significance for understanding the mechanism of photocatalytic reaction.The fifth chapter summarizes the work of this thesis,expounds the innovation of this thesis,and makes a preliminary outlook on the follow-up research of this thesis.