Decoration Of TiO₂ By Bismuth-based Materials And Their Photocatalytic Performance Under Visible Light

Photocatalytic technology is an effective method to solve the world energy crisis and global environmental pollution.Among them,TiO₂ nanobelts（NBs）,as a typical photocatalytic semiconductor,have the advantages of safety,high catalytic effect under ultraviolet light,fast carrier migration,and easy modification.Therefore,the TiO₂nanobelt,as a carrier,can be combined with other components in a controllable manner to improve its own visible light catalytic activity.In recent years,bismuth-based materials have attracted widespread attention due to their relatively positive valence band position and strong oxidation ability under visible light.Therefore,the TiO₂ NBs and the bismuth-based materials are combined to construct a heterostructure to enhance the visible light absorption of TiO₂,overcome the shortcomings of low photogenerated electron and hole separation efficiency and low recombination rate,and improve the photocatalytic performance of the material.In this work,the solvothermal method was used to synthesize Bi₂O₂CO₃/TiO₂hybrid（TB）with 0-dimensional/1-dimensional nanostructure.The characterization results proved that Bi₂O₂CO₃ quantum dots（QDs）with diameters of 1.40-1.50 nm were uniformly grown on the surface of TiO₂ NBs.TB exhibits excellent photocatalytic activity of rhodamine B under visible light,especially TB-3,which can degrade 95.43%of rhodamine B（150 min）.The heterojunction promotes the separation of carriers and prolongs the electron-hole lifetime.In addition,the controllable preparation of highly dispersible Bi₂O₂CO₃ QDs increases the specific surface area of the material and improves the efficiency of visible light catalytic reaction.The photocatalytic composite Bi⁰/Bi₂O₂CO₃/N-TiO₂（BNT）was synthesized by changing the solvent to ethylene glycol and ethylenediamine to expand the scope of photocatalytic materials and explore the influence of different solvents on the structure of the material.The characterization results showed that the introduction of ethylenediamine made TiO₂ successfully doped with N element,and the surface was uniformly modified with compound quantum dots combined with Bi⁰ and Bi₂O₂CO₃（diameter 1.2-2.1 nm）.Under visible light irradiation,BNT achieved an efficient degradation rate of 95.02%of the rhodamine B（180 min）.The doping of N element makes the material show photocatalytic activity under visible light,and the interaction between the three components makes the carriers move more quickly.