Preparation Of BiOCl Composites And Their Photocatalytic Degradation Of Some Antibiotics

With the accelerating process of industrialization in today's world,environmental pollution is particularly serious.The direct exposure of a large number of antibiotics in the environmental system will cause serious harm and influence to the environment and human body.Therefore,it is particularly necessary to develop simple and efficient pollution control and remediation technology.Photocatalytic degradation technology has attracted much attention due to its advantages of green and environmental protection.In recent years,many studies have shown that BiOCl materials have excellent light absorption properties,which is considered as a new type of photocatalyst with potential application value except Ti O₂.From the structural analysis,the crystal structure of this kind of material has[Bi₂O₂]²⁺and Cl^-alternate arrangement structure,but its band gap is relatively wide,it is difficult to directly absorb and use visible light.In order to improve the photocatalytic performance of BiOCl materials,the scientific community has modified and modified its structure through a variety of ways,such as metal or non-metal doping,semiconductor heterostructure construction,etc.In this paper,chlorella,glucose,KNbO₃ and BiOCl were used as raw materials to prepare a series of photocatalytic composites by hydrothermal and solvothermal methods,and their structures were characterized.TC and NOR were selected as the target pollutants.The photocatalytic activity of the prepared composite was evaluated,and the photocatalytic mechanism of the pollutants was described.The main research contents include:1.Preparation of carbon dots modified BiOCl material(CDs/BiOCl)and its photocatalytic degradation of TC.Using chlorella as the carbon source,a one-step solvothermal method was used to prepare carbon dots(CDs)modified BiOCl materials,and the photocatalytic degradation of TC was performed.When the oxygen atom in the crystal lattice of BiOCl is partially replaced by carbon atom,the band gap(E_g)becomes narrower,and the optical response can be extended from ultraviolet to visible light.CDs has remarkable electron acceptance and migration ability,which also provides structural support for the enhancement of charge separation efficiency of CDs/BiOCl.In addition,the functional density theory(DFT)was used to calculate the structural parameters of the composites to discuss the mechanism of action.2.Preparation of carbon microspheres modified BiOCl(001)crystal plane composites and their photocatalytic degradation of some antibiotics.The photocatalytic degradation of TC and NOR by carbon microspheres on the surface of BiOCl(001)was studied by hydrothermal and solvothermal methods.When the mass ratio of carbon microspheres to BiOCl was 1%,the degradation effect of TC and NOR was the best.Based on 3D-EEMS experiment and DFT theoretical calculation results,the degradation path and mechanism of NOR by CM/BiOCl composites were studied.3.Preparation and photocatalytic degradation of Z-scheme KNbO₃/BiOCl composites.KNbO₃/BiOCl heterojunction composites were prepared with KNbO₃ as substrate by hydrothermal and solvothermal methods.Taking TC as the target pollutant,the effects of composite material proportion,dosage and initial pollutant concentration on the degradation effect were discussed.BiOCl has excellent conversion photoluminescence performance due to doping of KNbO₃,which improves its utilization of light and accelerates the generation of active species,thus enhancing its photocatalytic degradation of TC.