Modified Design Based On Sheet Bi₂WO₆ And Reseach On Its Photodegradetion Of Phenolic Wastewater

With the rapid development of society,environmental pollution and energy problems have followed one after another,and people are urgently seeking an energy-saving and effective solution to environmental pollution problems.Compared with traditional technologies for solving environmental pollution problems,photocatalytic technology is a green technology that can solve pollution problems with the help of abundant solar energy in nature.Among many photocatalysts,Bi₂WO₆ has attracted wide attention of researchers due to its excellent photocatalytic efficiency,good stability and non-toxicity.In this paper,based on Bi₂WO₆,the semiconductor modification of Bi₂WO₆ is studied.The degradation of phenolic pollutants and the photocatalytic mechanism are discussed,and a Z-type heterojunction scheme is constructed to suppress the recombination of photogenerated electron holes.The specific research contents are as follows:?1?CuO/CNT/Bi₂WO₆ was synthesized by hydrothermal impregnation method using Bi₂WO₆ as a matrix.The effect of different ratios of CuO and Bi₂WO₆on the degradation performance was studied.As a result,the degradation effect of 3%CuO/CNT/Bi₂WO₆ on phenol is best.We have analyzed the material's micro-morphology,optical characteristics,and photocatalytic mechanism.The results show that the light absorption range becomes wider after doping CuO and CNT.The sandwich structure is formed by connecting two semiconductors with carbon nanotubes.It can form a Z-shaped heterostructure that makes the photo-generated holes of Bi2WO6 easier to play a role.With the cooperation of H2O2,CuO/CNT/Bi₂WO₆ can degrade phenol by 93%.?2?Using Bi2WO6 as a matrix,porous ZnO/Bi2WO6 was prepared by a combination of hydrothermal method and calcination.The effect of catalysts with different mass ratios on the degradation performance of phenols was tested.The best mass ratio was obtained by comparing the degradation rates.The degradation of phenol by?1:1?ZnO/Bi₂WO₆ can reach 99.3%.By studying the morphology,optical properties and element interactions of the catalyst,it can be concluded that the Z-type heterojunction structure is formed between ZnO and Bi₂WO₆ through Zn-O-W bonding.The Z-scheme structure is retained the conduction band potential of ZnO and the valence band holes of Bi₂WO_6.The large plate-like structure exposes more active sites and shortens the path of photo-generated holes and electrons transfer so that photo-generated holes participate in the reaction more effectively.?3?Using Bi₂WO₆ as a matrix,ZnTiO₃/Bi₂WO₆ photocatalysts with different molar ratios were synthesized by a two-step calcination hydrothermal method.The morphology and element interactions of photocatalyst were studied.It can be seen that ZnTiO₃/Bi₂WO₆ is formed by many cluster-like pieces attached on a large square.This structure can form a heterostructure to effectively separate photo-generated carriers.The optimal ratio of phenol degradation was tested by changing the molar ratio of ZnTiO₃.The molar ratio of?1.5:1?ZnTiO₃/Bi₂WO₆ has the best degradation performance.The cyclic degradation experiment also verified the stability of the photocatalyst.It is inferred from the quencher experiments that the photocatalytic degradation mechanism of ZnTiO₃/Bi₂WO₆ is a Z-type heterojunction mechanism.This study is dedicated to semiconductor modification using Bi₂WO₆ as the substrate.The modified photocatalyst forms a Z-type heterojunction between semiconductors to enhance its photocatalytic redox capacity.We have further studied the effects of morphology and band structure of photocatalysts on the photocatalytic degradation of phenol wastewater.It provides a feasible solution for the control of environmental pollution and the effective use of energy.