Controllable Construction And Degradation Antibiotics Performance Of Bismuth Oxychloride Composite Photocatalytic Materials

In recent years,the water environment pollution caused by excessive use of antibiotics is becoming more and more serious.There's a lot of evidence that small amounts of antibiotics in domestic water can endanger human health.Therefore,it is urgent issue to remove the residue antibiotics in water.The photocatalytic degradation technique shows potential application prospect in removing antibiotic pollutants owing to its simple,mild,fast,energy-saving,green,etc.advantages.BiOCl photocatalyst has attracted much attention due to its characteristics of high efficiency,stability,non-toxicity,low price,etc.However,its wide band gap,only responding to ultraviolet light and relatively low carriers'separation efficiency limit its practical application.Therefore,here N₂-doped carbon quantum dots?NCQDs?,hydrogenated titanium?H-TiO₂?and reduced graphene oxide?RGO?were used to construct composite photocatalytic materials to solve the above problems,so as to improve the photocatalytic degradation performance of antibiotics.XRD,FSEM,TEM,HRTEM,XPS etc.were used to investigate the microstructure,morphology,surface element distribution and valence states of the composite photocatalytic materials.N₂adsorption-desorption experiments,uv-vis DRS spectra,PL spectra,transient photocurrent and EIS plots were used to investigate the pore size structure,specific surface area,optical absorption properties and carriers'separation efficiency of the composite photocatalytic materials.The photodegradation mechanism of the composite photocatalytic materials was investigated by ESR and active species capture experiments.?1?The NCQDs/BiOCl composite photocatalytic material was constructed by NCQDs modified on the surface of three-dimensional?3D?flower spherical BiOCl,and its photocatalytic performance for degrading levofloxacin was investigated under the visible light.NCQDs was firstly prepared by hydrothermal method using glycine and glucose as raw materials,and then NCQDs/BiOCl composite photocatalytic material was prepared by NCQDs modified on the surface of 3D flower spherical BiOCl by solvothermal method.The surface modification of NCQDs reduces the band gap of BiOCl,expands the optical response range,and significantly improves the carrier separation efficiency.The photocatalytic performance of NCQDs/BiOCl composite photocatalytic material was significantly improved compared with that of BiOCl in the degradation of levofloxacin under the visible light.Investigations on photocatalytic reaction mechanism showed that·O₂^-and hole were the main active species in the degradation reaction of levofloxacin.?2?The H-TiO₂/BiOCl composite photocatalytic material was constructed by using H-TiO₂ and BiOCl,and its photocatalytic performance for degrading tetracycline hydrochloride was investigated under the visible light.Firstly,H-TiO₂was obtained by hydrogenation of commercial TiO₂?P25?as the raw material,and then H-TiO₂/BiOCl composite photocatalytic material was constructed by modifying H-TiO₂ on the surface of 3D flower spherical BiOCl by solvothermal method.Through the surface modification of H-TiO₂,the band gap of BiOCl is reduced,the light response range is widened,the transmission and separation efficiency of photogenerated electrons and holes is improved,and the carrier recombination is effectively inhibited.Compared with single BiOCl and H-TiO₂,the photocatalytic performance for degradig tetracycline hydrochloride was significantly enhanced under the visible light.The capture experiments of active species showed that·O₂^-and hole are the main active species in photocatalytic degradation.?3?RGO/H-TiO₂/BiOCl composite photocatalytic material was constructed by modifying H-TiO₂/BiOCl with RGO,and its photocatalytic performance for degrading tetracycline hydrochloride was investigated under the visible light.Firstly,RGO was prepared by Hummers method,and then RGO/H-TiO₂/BiOCl composite photocatalytic materials were obtained by one-step solvothermal method.The introduction of high-conductivity RGO resulted in further broadening the visible light response range of RGO/H-TiO₂/BiOCl composite photocatalytic materials,and the carriers'transport and separation efficiency was also grently improved,significantly enhancing the photocatalytic performance.Compared with BiOCl and H-TiO₂/BiOCl,the photocatalytic performance of RGO/H-TiO₂/BiOCl composite photocatalytic materials for degrading tetracycline hydrochloride was improved significantly under the visible light.The results of capture experiments showed that·O₂^-and hole were the main active species in the photocatalytic degradation of tetracycline hydrochloride...