Prepration Of Vanadium/Tantalum Based Materials And Application In Photodegradation Of Antibiotics Residues In Water Environment

Antibiotic resistance causes hundreds of thousands of deaths each year and is a major global health threat.Therefore,it is an urgent issue to deal with antibiotics residues in water environment.In recent years,photocatalytic oxidation technology has been widely used to degrade and purify pollutants with synergistically oxidants and UV lights.The pharmaceutical waste water and the intermediates can be photodegraded through the heterogeneous photocatalytic reaction process,which has the benefits of safety and low price.Meanwhile,the vanadium-based and tantalum-based materials have being focused most attention due to their excellent physical and chemical properties.The reserves of vanadium ore and tantalum ore in our country are sufficient.Their diverse valence states,excellent photoelectric performance and outstanding photocatalytic efficiency make vanadium-based and tantalum-based materials a rare high-quality photocatalytic material.Herein,the efficient photocatalysts was prepared to remove the antibiotics residues in water environment by modifying Ag₃VO₄,NH₄V₄O₁₀,BiVO₄,Bi₃TaO₇,and Sn₂Ta₂O₇nanomaterials.?1?Ag₃VO₄/mpg-C₃N₄?mesoporous graphitic carbon nitride?heterojunction photocatalysts were prepared by anchoring tiny Ag₃VO₄ particles on the nanosheet of mpg-C₃N₄.The prepared Ag₃VO₄/mpg-C₃N₄ heterojunctions were used to removal tetracycline?TC?under solar irradiation.Ag₃VO₄/mpg-C₃N₄ displayed higher photodegradation performance?83.2%removal rate within 90 min under visible-light irradiation?.In addition,a possible mechanism and intermediate products for the Ag₃VO₄/mpg-C₃N₄ photocatalysts towards the photodegradation of TC in aqueous solution under simulated sunlight irradiation was proposed based the scavengers trapping test,ESR spectra,and HPLC-MS.?2?Here we loaded the CdS quantum dots on the ultrathin NH₄V₄O₁₀ nanosheets by a facile heating reflux method.The special heterostructure provided larger surface area,promoted the separation,transfer of charges and offered abundant active sites for photocatalysts.The 0D/2D CdS/NH₄V₄O₁₀ photocatalysts were shown remarkable degradation performance and high stability for photodegradation of amoxicillin?AMX?due to the unique structural and compositional benefits.Meanwhile,the photodegradation pathway of AMX was also clarified by the DRS,PL,ESR test,HPLC-MS/MS analysis and active species capture experiment results.?3?The C₃N₄/NH₄V₄O₁₀ photocatalyst was prepared by simple reflux method,and the degradation property and mechanism of ciprofloxacin?CIP?were studied.The experimental results showed that the removal rate of CIP by C₃N₄/NH₄V₄O₁₀photocatalyst was 89.1%within 120 min,and showed high resuability after five cycles testing.Due to its unique 2D/2D structure,C₃N₄/NH₄V₄O₁₀ photocatalyst provides excellent adsorption activity and lots of active sites in photodegradation of CIP.Meanwhile,based on DRS,PL,ESR test and active species capture experiment results,the photodegradation mechanism of C₃N₄/NH₄V₄O₁₀ were clarified.?4?The carbon quantum dots?C-dots?mediated Sn₂Ta₂O₇/SnO₂ heterostructures with spongy structure were successfully assembled by simple hydrothermal route.The photocatalytic removal efficiency of amoxicillin?AMX?over C-dots/Sn₂Ta₂O₇/SnO₂ was estimated to reach up 88.3%within 120 min simulated solar light irradiating.The mechanism investigation proposed that with the C-dots modified,the photocatalysts improve the utilization of solar energy by harvesting the long wavelength solar light due to their unique up-converted photoluminescence?UCPL?.In addition,the porous spongy structure and plenty of tiny C-dots promote the ability of adsorption by enlarged specific surface area.Meanwhile,the HPLC-MS/MS analysis and density functional theory?DFT?computation were examined to clarify the photo-degradation pathway of AMX.?5?The C-dots/BiVO₄/Bi₃TaO₇ photocatalyst was synthesized by simple hydrothermal route,and the degradation property and mechanism of various antibiotics was also researched.The experimental results showed that the removal rate of TC,AMX and CIP by C-dots/BiVO₄/Bi₃TaO₇ photocatalyst was 91.7%,89.3%,87.1%,respectively,within 120 min,and showed high stability after ten cycles.Meanwhile,the antibiotics of TC,AMX and CIP were mixed to tested the practical application for C-dots/BiVO₄/Bi₃TaO₇ photocatalyst.based on DRS,PL,HPLC-MS analysis,ESR test and active species capture experiment results,the photodegradation mechanism of C-dots/BiVO₄/Bi₃TaO₇ were clarified.