Preparation And Catalytic Performance Of Iron Titanate Composite Photocatalyst

With the rapid development of industry,pollution has become a common challenge facing the world.Photocatalytic technology is considered to be one of the most promising research fields in the 21st century due to its green energy saving,no secondary pollution,and simple and efficient processes.Of course,the currently most widely used traditional photocatalyst Ti O₂ can only absorb ultraviolet light,and the utilization rate of sunlight is not high.In order to improve the use of sunlight,photocatalytic materials that respond to visible light have become a research hotspot.In this paper,the perovskite-type semiconductor material Fe₂Ti O₅ is used as the research object,and its light response range reaches visible light.We investigated the optimal synthesis route of Fe₂Ti O₅ precipitation method and the influencing factors of its photocatalytic performance.In addition,in view of its small specific surface area and electron-hole recombination disadvantages,we carried out modification studies using supported metal oxides?-Bi₂O₃ and precious metal Ag to further improve the visible light catalytic performance of the material.Through XRD?EDAX?SEM and other characterization of the product,we found that calcination temperature is 800°C,and the calcination time is 6 h,the morphology and size of the product particles are relatively uniform.The synthesized products are consistent with the standard Fe₂Ti O₅ card PDF#76-1158.The composition contains three elements of Fe,Ti,and O in a ratio of 2:1:5.The molten salt method was used to change the crystal structure.It was found that the final product of the molten salt was also Fe₂Ti O₅,and the particle size of the Fe₂Ti O₅ was larger than that of the unfused salt.The Fe₂Ti O₅ particles after the molten salt had a cubic phase structure.Methylene blue is mainly used to simulate pigment wastewater as the degradation target to screen photocatalytic reaction conditions.It was found that the amount of catalyst added was 75 mg,methylene blue solution 150 m L,the initial concentration of the solution was 10 mg/L,the solution p H was 6,and the addition amount of oxidant H₂O₂ was 7m L.The degradation rate was the highest,reaching 99.4%.In addition to determining a series of factors affecting the photocatalytic reaction,we repeated the reuse of the same group of catalysts four times.Fe₂Ti O₅ was not only easy to recover,but also found that the catalytic effect of the fourth time was only slightly reduced compared to the first time,which is in line with photocatalysts are low cost and energy efficient.We used?-Bi₂O₃ and Ag to modify the Fe₂Ti O₅ and characterized it by XRD,TEM and XPS.It was confirmed that?-Bi₂O₃ and Ag were successfully supported on the surface of Fe₂Ti O₅ particles.The degradation rate of the prepared?-Bi₂O₃/Fe₂Ti O₅ composite catalyst for methylene blue solution under visible light was 83.7%,and the degradation rate of Ag/Fe₂Ti O₅composite catalyst for methylene blue solution under visible light was 65%,both of which were higher than Fe₂Ti O₅.