Application and Research Progress of WO3-Based Composite Materials in Photocatalysis
The development and use of fossil energy not only promote the development of global economy,but also bring two major crises to human beings:environmental pollution and energy exhaustion.Based on this,the use of new energy,looking for green and efficient new energy conversion technology has become the focus of research.Photocatalysis,as a new green energy conversion technology,converts solar energy into chemical energy that can be directly used,which has been widely concerned by researchers.The principle of this technology is put forward by the solid energy band theory,that is,when the light with energy greater than the semiconductor band gap shines on the surface of the catalyst,the electrons in the valence band will be excited to jump to the conduction band,leaving a hole in the valence band.These holes and electrons can directly with the target molecule,can also with the catalyst surface adsorption of O2 and H2O or OH-reaction,generate reactive free radicals,and participate in the reaction.Due to the direct use of solar energy,photocatalytic technology has low consumption,clean and other innate advantages.At present,this technology has shown great application potential in the purification of environmental pollutants and the development of clean energy.In order to obtain higher conversion efficiency,the research on catalytic mechanism and structural modification of materials has become a hot topic in physical chemistry,materials science and environmental chemistry.The low e-h separation efficiency of catalyst materials is the main bottleneck hindering the practical application of photocatalytic technology.Among them,the construction of composite materials is considered to be one of the most effective ways to develop highly active photocatalysts.On the one hand,the composite catalyst can combine the advantages of different materials into one,thus significantly expanding its application range.On the other hand,the carrier can migrate to the surface of different components,which can effectively improve the separation efficiency of photogenerated charge through physical isolation.Among many semiconductor materials,tungsten trioxide(WO3)is popular because of its good visible light response(band gap around 2.70 eV)and excellent valence band hole oxidation ability.Driven by the pursuit of higher hole efficiency,a large number of WO3 based composite photocatalysts have been constructed and reported,and their applications cover many fields.In order to make the design and application of WO3 based composite photocatalytic materials more rational development,and to provide useful reference for peers,it is urgent to summarize and review relevant studies regularly.In this paper,the application and research progress of WO3 based composite in photocatalysis in recent years are systematically summarized.Starting from structural characteristics of WO3 itself,around the composite preparation methods and the characteristics of composite material structure and performance of structure-activity relationship between two hot issues were summarized,and finally expounds the existing WO3 based composite photocatalyst in the decomposition of aquatic product hydrogen,CO2 reduction,nitrogen fixation,and the application of pollutants removal in areas such as the status quo,and the prospects of the development prospect was put forward.
NETL
NSTL
万方数据
