Microstructure Modulation And Performance Research Of Ternary Metal Oxide/Sulfide Photocatalysts

Photocatalytic technology can effectively utilize sunlight and posses the characteristics of the deep reaction that can be achieved at room temperature,which has great application prospects in environmental governance and energy crisis mitigation and has received extensive attention from scientific researchers.However,photocatalytic materials have narrow spectral response range,poor selective adsorption performance,easy recombination of carriers and low quantum efficiency resulting in low catalytic efficiency of photocatalysts.Therefore,the design and synthesis of new and highly efficient photocatalytic materials is a pivotal research topic in this field.In recent years,Bimush-based photocatalytic materials have exhibited surprior photocatalytic activities for the degradation of pollutants,photocatalytic nitrogen fixation and spectrum sterilization.However,their visible light response range is narrow,the separation of photoinduced electron and hole pairs is difficult;metal sulfides have good visible light response ability display excellent photochemical activity for photocatalytic water pholysis and CO₂ reduction,but their photocorrion is severe,and stability is poor,photogenerated carriers are easily compounded and the quantum efficiency is low.In view of the above problems the research work in this paper mainly includes the following two aspects:（1）The synthesis and modification of Bi-based photocatalytic materials with morphology and crystal surface control and the improvement of the new type through the construction of morphology and the control of crystal faces.Photocatalytic Efficiency of Photocatalyst Bi₂O₂SiO₃.（2）Controllable synthesis and photocatalytic performance of ternary metal sulfides.Thus,the regulation of microstructure ternary metal sulfides with hollow structure and excellent photochemical activity and stability were designed and prepared.The research work is mainly divided into the following two parts.Part 1 The single-phase Bi₂O₂SiO₃ was synthesized by controlling the pH value to inhibit the hydrolysis of SiO₃^2-and the coordination effect of surfactant cetyltrimethylammonium bromide（CTAB）with oxygen atoms in Bi₂O₂SiO₃.To modulate the exposure ratio growth direction and morphology of the{001}crystal of Bi2O2SiO3 single crystal nanosheet with{001}crystal surface exposed band structure was synthesized for the first time.The results of comparative experiments show that Bi₂O₂SiO₃ with high exposure ratio of{001}crystal surface shows excellent photocatalytic activity for degradation of RhB and BPA under simulated sunlight irradiation.The main reason for the increase in catalytic activity is the increase in the exposure ratio and oxygen vacancy concentration of the{001}crystal plane.Part 2 Ternary metal sulfide MIn₂S₄（M=Zn,Ca,Mg,Mn）with a hollow sphere structure was synthesized by using the biomolecule glutathione as the source of sulfur source and gas template and using it to release CO₂ and NH₃ as templates under high temperature conditions yolk-shell structure of CdIn₂S₄.The growth mechanism morphology evolution process and photocatalytic reaction mechanism of CdIn₂S₄microspheres have been studied.The formation process of CdIn₂S₄ flowerlike microspheres is Oswald ripening effect.The experimental results show that our synthesis method is versatile and universal the yolk-shell structure of CdIn₂S₄ for the degradation of reactive brilliant red X₃B photolysis of hydrogen produced by water showed excellent performance which is 6 times and 36.6 times that of commercial CdS.The excellent photocatalytic activity of CdIn₂S₄ microspheres is attributed to its smaller crystal size and unique structural advantages of yolk-shell structures.