Preparation Of Bismuth Oxide And Zinc Oxide Doped Bismuth Oxide Photocatalysts And Study On Degradation Of Methyl Orange

Energy issues and environmental pollution are seriously threatening the sustainable development of mankind,photocatalytic oxidation technology has many advantages in the field of water treatment because of its many advantages such as direct utilization of light energy,mild conditions,and clean process.Among many photocatalyst semiconductors Bi₂O₃ semiconductors have a relatively narrow bandgap,which has a certain photocatalytic effect in the visible range,but in order to further expand its response intensity and range in the visible range,metal doping is modified.Sex is very necessary.In this paper,ZnO was used as a modifier to modify the Bi₂O₃ photocatalyst and the photocatalytic performance was also tested and tested.?1?Undoped Bi₂O₃ and ZnO photocatalysts were synthesized by hot water method.Tests have shown that the undoped ZnO photocatalyst has a predominantly hexagonal crystal structure with a band gap of 3.06 eV.The Bi₂O₃ photocatalyst is a sheet-like monoclinic pHase ?-Bi₂O₃ structure with a forbidden band width of 2.87 eV.?2?ZnO-doped modified Bi₂O₃ photocatalysts were prepared by hot water method and sol-gel method.The test results show that the different ZnO doping amount has a great influence on the XRD,SEM,UV-Vis and BET of the photocatalyst prepared by the two methods.The doped modified photocatalyst obtained by the two methods is a mixed crystal structure;when Zn/Bi=0.03,the forbidden band width of the ZnO-doped Bi₂O₃ photocatalyst prepared by the two methods is the smallest,and the forbidden band width is respectively 2.76 eV and 2.79 eV.The SEM and BET test results show that when Zn/Bi=0.03,the specific surface area of the photocatalyst prepared by the two methods is maximized,and the photocatalyst particle size is the smallest.?3?The photocatalytic degradation experiment of methyl orange showed that the optimum catalyst input amount of undoped Bi₂O₃ and ZnO photocatalyst was:0.06 g of Bi₂O₃ used in 100 mL concentration of 15 mg/L methyl orange,ZnO is 0.08 g.The initial concentration of methyl orange degradation is preferably 15 mg/L.?4?The ZnO doped Bi₂O₃ photocatalyst prepared by hot water method and sol-gel method was used in the degradation experiment of methyl orange wastewater.The research shows that the amount of photocatalyst prepared by hot water method is 0.06 g/100 mL methyl orange solution,degraded for 1h,the ZnO doping amount is Zn/Bi=0.03,the hot water temperature during the preparation of the catalyst is 160 ?,the pH of the solution is 1-3,the photocatalyst shows better light.Catalytic degradation effect.Its optimal photocatalytic degradation efficiency can reach 98.89%.When the amount of the sol-gel macrocatalyst is 0.08 g/100 mL of methyl orange solution,the ZnO doping amount is Zn/Bi=0.03,the photocatalyst calcination temperature is 400 ?,and the solution pH=3,the photocatalyst shows better photocatalytic degradation.Its optimal photocatalytic degradation efficiency can reach 95.13%.The preparation of zinc-doped cerium oxide photocatalyst by hot water method is more advantageous than the sol-gel method.The photocatalytic effect of different photocatalysts is:ZnO doped Bi₂O₃>Bi₂O₃>ZnO.