Study On Preparation And Catalytic Performance Of Graphene Like Molybdenum Disulfide Nanosheets

Molybdenum disulfide?MoS₂?is a kind of two-dimensional?2D?layered material with graphene like structure,which belongs to the category of transition metal sulfides MX2,in which M and X are corresponding to transition metals and sulfides.They are covalently bonded,and there is a Fan Dehua force between the layers.Due to its special layered structure,it has attracted many researchers' attention in the fields of catalysis,electricity,optics and so on.In this paper,the preparation and catalytic performance of graphene like MoS₂ nanosheets were studied.Commercial MoS₂ as raw material,the MoS₂ nanosheets were successfully separated by low energy ball milling and ultrasonic method.The crystal structure and morphology were analyzed by XRD,SEM,HRTEM and AFM,and the effects of different preparation parameters on the experimental results were discussed.The results show that the thickness of MoS₂ nanosheets prepared by the above method is 1-3,and the morphology is uniform and the stability is good.The optimum preparation conditions were as follows: NMP was used as solvent,the milling time was 24 h,and the ultrasonic time was 6h.Ag₃PO₄/MoS₂ nanosheets composite catalyst was prepared by ball milling method.The structure and properties of the samples were tested and analyzed.The results show that after the visible light irradiation 25 min,the degradation rate of Ag₃PO₄/MoS₂ nanosheets composite material can reach 93%,which is much higher than that of pure Ag3PO4 by methylene blue as the pollutant.By repeated tests,MoS₂ nanosheets can effectively improve the stability of Ag3PO4?g-C₃N₄ powders were prepared by high temperature pyrolysis of melamine,and g-C₃N₄ and MoS₂ nanosheets were successfully synthesized by ball milling.Through the characterization of the structure and photocatalytic properties of the samples,it was found that the g-C₃N₄ and MoS₂ nanosheets formed a heterogeneous structure,which effectively improved the photocatalytic performance of g-C₃N₄.Among them,the rhodamine B as a pollutant,after visible light irradiation of 120 min,the content of MoS₂ nanosheets films with 2% g-C₃N₄ of the highest degradation rate of the sample,the degradation rate was 97%.At the same time,the photogenerated hole plays an important role in the photocatalytic reactionThe g-C₃N₄/MoS₂ nanosheets /GO composite was prepared by ball milling method,and its structure and properties were tested and analyzed.With the addition of MoS₂ and GO,the particle size of g-C₃N₄ decreases,and the thin layer becomes thinner.At the same time,as a carrier,GO can provide more photon energy and photocatalytic reaction active sites for the g-C₃N₄/MoS₂ nanosheets,thus improving the photocatalytic performance of g-C₃N₄.Compared with the single MoS₂ nanosheets and GO,the synergistic effect of both can significantly improve the photocatalytic performance of g-C₃N₄.Among them,the rate of Rhb degradation of 80/20 MG samples under visible light was 2.9 times,1.7 times,and 1.6 times of g-C₃N₄,0.3%MN and 0.3%NG,respectively.