Regulation Of Electron Spin Magnetic Moment Of Transition Metal Oxide And Its Effect On Microwave Induced Oxidation Degradation

The relationship between 3d electron spin magnetic moment,microwave loss mechanism and microwave induced degradation mechanism were mainly studied in the thesis.In order to further explore the effect of spin magnetic moment on microwave induced oxidative degradation,this paper synthesized a series of transition metal oxides with three spinel structures using Zn²⁺and Al³⁺isomorphism respectively to replace M²⁺?M:Co,Fe,Mn?and M³⁺?M:Co,Fe,Mn?.The effects of composition and morphology on microwave induced oxidative degradation were studied by means of structure regulation.By measuring the microwave absorption performance,dielectric loss and magnetic loss,as well as a series of experimental comparison of microwave induced degradation of tetracycline by spinel oxide,the relationship between the microwave loss mechanism caused by 3d electron spin magnetic moment and the microwave induced degradation mechanism was studied and revealed.The main conclusions are as follows:?1?Cobalt oxide was successfully prepared by hydrothermal-calcining method,and iron oxide and manganese oxide were directly synthesized by hydrothermal method.The results showed that Zn²⁺and Al³⁺were successfully doped into the crystal lattice of M3O4?M:Co,Fe,Mn?respectively,and the crystal system and spatial group did not change.For Co₃O₄,Zn²⁺doping did not change the morphology,which were all spherical particles with diameter of about 6-7?m,while Al³⁺doping changed the morphology into cube block particles with side length of 7-9?m.For Fe₃O₄,Al³⁺doping did not change the morphology,and both were spherical particles with a diameter of about 400nm,while Zn²⁺doping reduced the diameter to about 100nm.For Mn₃O₄,the doping of Zn²⁺did not change the morphology,which was a uniform octahedral particle.The doping of Al³⁺gradually changed the morphology into a fish-like lamellar shape.?2?Microwave-induced degradation of tetracycline by Co₃O₄ and Fe₃O₄ reached47.7mg/g and 47.8mg/g,respectively.Zn²⁺had no effect on the microwave-induced degradation,while Al³⁺reduced the microwave degradation rate and prolonged the equilibrium time.Microwave induced degradation of tetracycline by Mn₃O₄ reached42.81mg/g.Zn²⁺reduced the degradation rate,reduced the degradation amount and prolonged the equilibrium time.Al³⁺had no effect on the microwave induced degradation.?3?The order of microwave absorption properties of cobalt,iron and manganese oxides is consistent with the magnitude of the respective electron spin magnetic moments.The electron spin magnetic moment of the three oxides was positively correlated with microwave degradation and microwave absorption performance.