Construction Of Molybdenum Disulfide Composite Catalyst And Activation Of Persulfate For Antibiotic Degradation

As a new advanced oxidation technology,the advanced oxidation technology of persulfate can effectively remove antibiotics from water.Molybdenum disulfide(MoS2)has attracted extensive attention of scientific researchers because of its unique electronic structure and good photoelectric chemical properties.In order to overcome the problems of weak enrichment ability and low activation efficiency in the process of MoS2 activated persulfate degradation of antibiotics,it is urgent to improve the charge transport ability and enhance the enrichment ability of antibiotics,so as to achieve efficient removal of antibiotics in water.In this paper,a series of MoS2 composite catalysts modified by transition oxides were prepared using the heterojunction construction strategy.The performance of the composite catalysts to activate persulfate to degrade antibiotics was investigated,and the relationship between the microstructure of the composite catalysts and the enhancement of persulfate activation efficiency was elucidated,providing a new way for the effective removal of antibiotics in water.Specific research work is as follows:(1)CoFe2O4@MoS2 composite was synthesized by a simple hydrothermal method.By activating persulfate(PS),TC can be degraded by 70%,which is about 40 times of the original MoS2.CoFe2O4@MoS2 system can effectively remove tetracycline over a wide pH range(2-9),which broadens the application of catalysts under alkaline conditions.Because MoS2 is chemically stable and not easily soluble in water,CoFe2O4@MoS2 composite catalyst can selectively contact TC molecules in wastewater.Meanwhile,the ultra-high conductivity and electron transfer rate on the surface of MOS2 make charge transfer from electrode to pollutant rapidly.And produce a large number of free radicals(·OH,SO4·-,·O2)and non-free radicals(1O2),effectively remove tetracycline in the reaction system.In conclusion,CoFe2O4@MoS2 composite materials have potential application value in the field of water environment remediation.(2)α-FeOOH@MoS2 composite catalyst was prepared by preparing α-FeOOH modified MoS2.Compared with MoS2,α-FeOOH improves the catalytic activity and pH adaptability of the α-FeOOH@MoS2 composite.The α-FeOOH@MoS2 system activates persulfate(PMS)to degrade tetracycline in the pH range of 3～11 and maintains good catalytic activity after cycle 4.Therefore,α-FeOOH@MoS2 shows very high catalytic activity and stability.(3)MoS2 was modified by synthesizing iron oxide α-Fe2O3 substituted ions,andα-Fe2O3@MoS2 nanocomposites were synthesized by hydrothermal method.In the activated PMS system,100%tetracycline was removed within 30min.Compared with MoS2,the introduction of iron oxide promotes the REDOX cycle of Fe and Mo ions to produce active free substances(·OH,SO4·-,O2·-,1O2).The addition of α-Fe2O3 improves the catalytic activity and pH adaptation range of α-Fe2O3@MoS2 composites.In the pH range of 3～11,α-Fe2O3@MoS2 system can activate persulfate(PMS)to degrade tetracycline and maintain good catalytic activity after cycle 4.