Preparation Of Cu₂O Composite Semiconductor Particles And Properties Of Degradation Ciprofloxacin

With the development industry and the improvement of living standard,the use of antibiotics has gradually increased,and most humans and animals absorb a little antibiotics,and most of them are released into the environment in the form of raw materials,caused pollution of water resources by the circulation.Its a narrow bandgap semiconductor material,Cu2O has a bandgap of about 2.0 eV,can effectively absorb the visible light band,and has potential application value in the field of photocatalytic degradation of pollutants.However,the easy recombination of photoelectrons and holes restricts the photocatalytic performance of Cu2O.Modification of Cu2O can not only improve the photoelectron and hole separation efficiency of Cu2O,but also improve the photoresponse range of Cu2O and increase the utilization of sunlight.In this paper,Cu2O particles were prepared by solvothermal method.The crystal structure,microscopic morphology and optical properties of the particles were analyzed by XRD,UV-Vis,SEM and N2 adsorption and desorption.The electrochemical properties of the particles were tested.The specific research content is as follows:(1)Prepare the conditions and properties of Cu2O particles by solvothermal method.The results show that the prepared Cu2O particles have higher purity and better absorbance at 130℃.The reaction time was 23 h and 25 h.Cu and CuO impurity peaks appeared.Cu2O particles has higher purity after 24 h.The dispersibility of Cu2O particles gradually becomes better with the increase of PVP addition amount,but the agglomeration phenomenon decreases,showing a dodecahedron;among them,R2-Cu2O exhibits a good absorbance value;The results of electrochemical performance analysis that surface resistances of R1,R2,and R3-Cu2O were 2987 Ω,3576 Ω,and 14582 Ω,respectively.The degradation rates of R1,R2,and R3-Cu2O were 66.65%by photocatalytic degradation of ciprofloxacin.,73.12%and 54.64%,R2-Cu2O has the highest degradation efficiency.Therefore,Cu2O particles were prepared under the optimal conditions of reaction temperature 130℃,reaction time 24 h and PVP optimum addition amount 1.0 g.(2)Preparation and properties of ZnCl2 doped Cu2O.The effect of different doping amount of ZnCl2 on the structure and properties of Cu2O was studied.The purity of Cu2O particles prepared in different systems was higher than that of pure Cu2O.The structure of the Cu2O particles was a chalcopyrite structure,and the band gap of the Cu2O showed a obviously difference.The forbidden band width of the miscellaneous Cu2O increases,and at the same time,the specific surface area increases;the micro structure of Cu2O also shows obvious changes,and the doped R4,R5,and R6-Cu2O morphologies are changed from dodecahedron of Cu2O to regular hexahedron,octahedron,and irregular morphology.Hexahedron,octahedron and irregular morphology;through the impedance analysis of AC,R5-Cu2O has a small electrical resistance,showing excellent electron-hole separation efficiency,and the degradation rate of ciprofloxacin reached 83.36%.(3)Preparation and properties of ZnO/Cu2O composite particles.The results show that the ZnO prepared by solvothermal method has high purity and exhibits nano-lamellar structure.The absorption range of light is mainly in the ultraviolet region.By studying the properties of ZnO and Cu2O composite particles with different qualities,the purity of ZnO/Cu2O composite particles prepared under different systems has a more obvious change.R7 shows more ZnO peaks,and R8 and R9 have higher values.The purity of ZnO/Cu2O composite particles was lower than that of Cu2O,the bandgap width was increased,the specific surface area was increased,the change of morphology was obvious,and the ZnO/Cu2O composite particles exhibited an octahedral topography.A large amount of ZnO has appeared around R8;through the AC impedance analysis,the resistance of R9 is obviously reduced,showing a good electron-hole separation efficiency,and having better photocatalytic performance.(4)Study on the degradation kinetics and mechanism of ciprofloxacin.The photocatalytic degradation of ciprofloxacin by R9 is in accordance with the first-order kinetics equation.The photocatalytic degradation of ciprofloxacin by the quencher added with different active species has been studied.The results show that ·OH can plays a role in degrade ciprofloxacin by photocatalysis.LC-MS/MS was used to analyze the intermediates degraded by ciprofloxacin and found that there were 8 kinds of main intermediates.Combining with Gaussian 09,the front cloud density and point charge of ciprofloxacin were calculated.The degradation pathway of ciprofloxacin was proposed.