The SPR Effect Enhances The Preparation And Performance Of Bi₂MoO₆/TiO_2-x Visible Light Catalyst

Environmental governance and energy development have become the two major themes of contemporary society.In order to realize the harmonious development of people and the environment,people have carried out multi-faceted exploration and research.With continuous research,semiconductor photocatalytic technology has considerable potential and prospects for the decomposition of organic pollutants and the generation of hydrogen.Among them,TiO₂ semiconductor materials gradually enter people's field of vision because of its advantages of non-toxicity,low cost,environmental protection and good stability.However,with the deepening of its research,it has been found that TiO₂ has a wide band gap?3.2 eV?,so it only responds to ultraviolet light.Moreover,there are large recombination rates of photogenerated electrons and holes in the photocatalytic process.These two defects seriously affect the photocatalytic performance and practical application of TiO₂.Therefore,the modification treatment of TiO₂ to improve its photocatalytic activity has become a widely used means.In this paper,TiO₂ is modified to form a composite product of two different systems—Bi-BMO/TiO_2-x-x microspheres and H-Ag-BMO/TiO₂.In both composite systems,there are heterojunction structures,surface plasmon resonance effects?SPR?of metal elements,and Ti³⁺and oxygen vacancies.In order to prove their existence and function,the morphological characteristics,crystal structure,element type and optical properties of the two samples were characterized in this paper.Moreover,their photodegradation ability and photocatalytic hydrogen production efficiency were tested under visible light.Finally,their photocatalytic mechanisms were analyzed and summarized,and the effects of each modification method were elaborated.The content of this paper mainly includes:?1?Bi-SPR-enhanced Bi₂MoO₆/black TiO₂ microspheres were successfully prepared by solvothermal method and in-situ solid state reduction method combined with TiO₂ sol-gel method.The photocatalytic performance of this new photocatalyst was tested under visible light.The photocatalytic degradation efficiency of Rhodamine B is 92.6%,and the hydrogen production efficiency is 62.4?mol h^-11 g^-1,showing excellent photocatalytic activity.The reason is that the separation efficiency of the photogenerated carriers is improved by the heterojunction structure,the SPR effect of the metal Bi,and the Ti³⁺and oxygen.Simultaneously,the responsiveness to visible light is also enhanced.?2?In order to explore the effects of different morphological combinations and SPR effects of different metal elements on the photocatalytic performance of the composite system,in this paper,surface hydrogenation Ag/Bi₂MoO₆ nanosheet/TiO₂nanobelt ternary composite system was successfully prepared by solvothermal method,photodeposition method and surface hydrogenation reduction method.The photocatalytic performance of this new photocatalyst was tested under visible light.The photocatalytic degradation efficiency of Rhodamine B is 96.5%,and the corresponding hydrogen production efficiency is 143.5?mol h^-11 g^-1,which has more excellent photocatalytic performance.The mechanism is also that the separation efficiency of the photogenerated carriers is enhanced by the interaction of the heterojunction,the SPR effect of Ag and the Ti³⁺,at the same time,the visible light response is also enhanced.By comparing the photocatalytic properties of the two photocatalysts,the performance of H-Ag-BMO/TiO₂ is significantly higher than that of Bi-BMO/TiO_2-x-x microspheres,indicating that nano-scale H-Ag-BMO/TiO₂ has a larger specific surface area and can expose more active sites.Moreover,the SPR effect of Ag improves the photocatalytic performance better than Bi.