Preparation And Photoelectrocatalytic Properties Of WO₃/Bi₂O₃ Composites

If solar energy is used reasonably by people,it can solve many problems in today’s society,such as energy shortage and environmental pollution.Nowadays,solar energy utilization technologies include photocatalysis,electrocatalysis and photoelectric catalysis.Photoelectric catalysis technology,which combines photoelectricity with synergy,has attracted great attention in recent years.Photoelectric catalytic technology can convert solar energy into chemical energy to solve the problem of energy shortage,and also can improve environmental pollution.In photocatalytic technology,semiconductors are often used as photocatalysts.As a common photocatalyst,tungsten trioxide（WO₃）has been widely used in the field of photoelectric catalysis.However,due to the shortcomings of tungsten trioxide itself,such as the wide band gap,the separation of electron-hole pairs is inhibited,which seriously affects the photoelectrochemical activity of tungsten trioxide.Therefore,we need to modify tungsten trioxide.In this paper,different composite materials were prepared by using WO₃as the matrix and compounding with semiconductors on FTO conductive glass to improve the performance of tungsten trioxide.The main research contents are as follows:（1）WO₃thin film was prepared on FTO conductive glass by hydrothermal method,and Bi₂O₃was grown on WO₃to form composite materials.By changing the amount of Bi₂O₃and hydrothermal time,the composite with the best properties was obtained.The structure,morphology and elemental composition of the heterojunction material were analyzed,and its photoelectrochemical properties were studied by electrochemical workstation.The results show that the photocurrent of WO₃/Bi₂O₃composites is significantly enhanced compared with that of WO₃and Bi₂O₃.When the hydrothermal time is 8h and the Bi₂O₃content is 50%,the photocurrent of the heterojunction material is the largest,which is 4.5 times of WO₃.（2）UiO66（Zr）was grown on the WO₃/Bi₂O₃composite material by hydrothermal method,and the WO₃/Bi₂O₃/UiO66（Zr）ternary material was prepared.It was characterized by XRD,SEM,TEM,UV-vis DRS,etc.,and the photoelectrochemical activity of the material was analyzed.The results show that the 25%WO₃/Bi₂O₃/UiO66（Zr）ternary material has the highest photocurrent and the best response intensity to light,which is 13 times and 2.9 times that of WO₃and WO₃/Bi₂O₃.