Research On Synthesis Of Graphene Doped Fe-based Nanometerials And Application Of Pollutants Degradation In Water

There are lots of advantages on advanced oxidation process（AOPs）based on persulfate,such as low cost,easy control,and low environmental impact.Previous researchs have indicated that transition metals doped graphene as catalysts can activate peroxymonosulfate.Among various transition metals,iron group compounds have been widely researched and applied to persulfate activation.However,traditional nano-zero-valent iron or iron oxide exist some disadvantages,such as poor stability、iron leaching and low removal efficiency.It is necessary to prepare an iron catalyst with high dispersion and stability for persulfate activation.Single atom catalysts（SACs）are a pionner in catalyst due to its minimum atomic size and maximum metal utilization,excellent catalytic activity and stability.It has promising application prospects in heterogeneous,however,it tends to be failed due to metal become nano-particals.To overcome above problems,In this study,a one-pot method successfully synthesis Fe-MNG,single atom iron-doped graphene（SA-Fe/graphene）.The above two nanomaterials are characterized and applied to activated persulfate to degrade pollutants.The research contents are divided into three sections:（1）Magnetic graphene with dual catalytic sites for efficient degradtion of antibiotics via heterogeneous activiation of PMSIn this study,a low-cost,environmentally friendly Fe₂O₃、Fe₃N and single atom Fe and nitrogen-doped magnetic graphene（Fe-MNG）nanomaterials were successfully prepared through one-pot method.Fe-MNG have dual catalytic active sites,which is easy to separate and recycle.Fe-MNG can efficiently activate PMS to degrade antibiotic.The Fe-MNG/PMS system can degrade sulfisoxazole（SIZ）in a wide p H range（3-10）,and has excellent stability and reusability.The degradation rate is keep above 95%.This research system explored the effects of catalyst dosage、oxidizer dosage and different experimental systems on SIZ degradation.The study find that Fe-MNG/PMS system have different catalytic oxidation processes,including free radical processes and non-radical processes.（2）Magnetic graphene with dual catalytic sites for efficient degradtion of bisphenol A via activiation H₂O₂.In this study,the Fe-MNG catalyst is further studied and applied to activate H₂O₂to degrade bisphenol A（BPA）.Compared with the traditional Fenton reaction,this material can effectively catalyze and activate H₂O₂ to degrade BPA under p H 3-5,which overcomes the shortcomings of reaction under weakly acidic conditions to a certain extent.At the same time,the Fe-MNG catalyst has good recycling performance,indicating that the catalyst has potential application prospects.Finally,the mechanism of Fe-MNG/H₂O₂degradation of BPA is proposed.（3）SA-Fe/graphene activates PMS to degrade sulfamethoxazoleA single-atom iron doped graphene catalyst（SA-Fe/graphene）was prepared by a simple synthesis method.The oxidative degradation performance of the catalyst under different conditions was studied,and the results showed that the SA-Fe/graphene/PMS system can efficiently degrade sulfamethoxazole（SMX）.In addition,SA-Fe/graphene also has excellent cycle performance.The quenching experiment and electron spin resonance spectroscopy（ESR）have confirmed that the SA-Fe/graphene/PMS system produces a variety of oxidative species,including HO·radicals,SO₄·^–radicals and singlet oxygen ¹O₂.This research provides new prospect for the synthesis of single-atom catalysts and applications in water treatment.