Preparation and Photoelectric Properties of Tungsten Trioxide Composite Films

Author:Wang Zhen Xing

Supervisor:cui hai ning

Database:Doctor

Degree Year:2019

Download:35

Pages:135

Size:6985K

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With the gradual depletion of traditional fossil energy sources and the increasing global environmental pollution problems,people are constantly seeking new energy-saving materials and new,sustainable,renewable green energy sources.WO3 is a very typical transition metal oxide semiconductor material.It exhibits special optical,electrical and mechanical properties due to its valence diversity and unique valence electron configuration.WO3 has shown excellent performance in the fields of electrochromism,catalysis,gas sensors,supercapacitor and solar cells.It will have great development and application prospects as the energy-saving material and the clean energy material in the future.In this paper,WO3 material is the main research object.A series of composite films based on WO3 were prepared by stacking and co-sputtering methods using Radio Frequency magnetron sputtering technology.The effect of laminate thickness and sputtering power on the optoelectronic properties of WO3 films was investigated.The specific research contents are as follows:(1)The film samples were prepared by Radio Frequency magnetron sputtering using ITO conductive glass as the substrate.TiO2/WO3 composite films with different thickness of TiO2 film layer were prepared by lamination method.We tested and analyzed the effect of the thickness of the TiO2 film layer on the transmission spectrum and electrochromic properties of WO3 film.The superposition of TiO2 film layer successfully improved the electrochromic stability of WO3 film.The optimal superposition thickness of the TiO2 film layer was determined by experiments.We successfully obtained 1.7-fold ion diffusion coefficient enhancement and the electrochromic stability was improved by more than 2 times.(2)WO3 films with suitable thickness were deposited on glass substrate by Radio Frequency magnetron sputtering.Cu2S film layer was deposited on the WO3film layer which was heat to prepare Cu2S/WO3 composite film.Cu2S/WO3composite films with different thickness of Cu2S film were prepared by controlling the thickness of Cu2S film.We used methylene blue as a simulated pollutant to test the photocatalytic performance of the Cu2S/WO3 composite films.We tested and analyzed the effect of the superposition thickness of Cu2S layer on the light transmission and photocatalytic activity of WO3 film.The superposition of Cu2S film layer successfully improved the photocatalytic activity of WO3 film.The optimal superposition thickness of Cu2S film was determined by experiments,and We successfully obtained 2.14-fold photocatalytic reaction coefficient enhancement.(3)WO3:TiO2 composite film samples were prepared by dual targets co-sputtering method.WO3:TiO2 composite film samples with different sputtering power ratios were prepared by changing the sputtering power of TiO2 and maintaining the sputtering power of WO3 steady.Then the samples were heat treated.We studied the changes of WO3 film on morphology and structure due to the incorporation of TiO2.The addition of TiO2 not only greatly improved the thermal stability of the WO3 film,but also made it easylly crystallize at a lower temperature.We used methylene blue as a simulated pollutant to test the photocatalytic performance of WO3:TiO2 composite film.The addition of TiO2 enhanced the photocatalytic activity of WO3 film.We determined the optimal sputtering power of TiO2 through experiments.The best photocatalytic degradation efficiency of methylene blue was as high as 72%,showing a high application potential.