Preparation And Visible-light Photocatalytic Performance Of RGO/Antimony(Bismuth) Sulfide Nanocomposites

Due to the good electron transport capabilities of graphene,if graphene is compounded with the semiconductor material,the recombination of photogenerated electron-hole pairs can be effectively prevented,then the photocatalytic activity of the semiconductor material can be significantly enhanced.Therefore,the graphene/antimony sulfide(RGO/Sb₂S₃)composites were prepared by hydrothermal and mixed solvothermal method,and graphene/bismuth sulfide(RGO/Bi₂S₃)composites were prepared by microwave method.A series of characterizations and photocatalytic performance tests showed that RGO/antimony(bismuth)sulfide had excellent photocatalytic activity.The specific content is as follow:(1)Graphene oxide(GO)was successfully prepared by modified Hummers method.Then,using GO,TAA(thioacetamide),SbCl₃,concentrated hydrochloric acid and sodium citrate as raw materials,water as solvent,RGO/Sb₂S₃was prepared by hydrothermal method.The results showed that the product was orthorhombic crystal system,and it had high crystallinity and purity.The hydroxyl,carboxyl and epoxy groups in GO could be partly or completely reduced by TAA when reacting at 200°C for 24 h.Scanning electron microscope(SEM)analysis showed that the amount of sodium citrate had little effect on the product morphology.The degradation rate of rhodamine B(Rh B)could reach 91.52%under the 350 W xenon lamp irradiate for 320min with the RGO/Sb₂S₃-1.5 as photocatalyst,and the good photocatalytic stability was confirmed by circulating photocatalytic experiments.In addition,it was confirmed that the·OH was the main active group in the photocatalysis process through terephthalic acid photoluminescence(TA-PL)detection technology and the photocatalytic contral experiment of adding Vc.(2)The RGO/Sb₂S₃nanocomposites were successfully prepared by mixed solvothermal method,using GO,SbCl₃,Na OH and L-cystine as the raw materials,water and ethylene glycol(EG)as mixed solvent.The results showed that the products had good crystallinity and were belong to orthorhombic.SEM analysis showed that different GO concentration,mixed solvent ratio,reaction temperature and time had a greater impact on the product morphology and composite effect with graphene.PL spectrum showed that the charge separation between conduction band and valence band was accelerated by combining graphene with Sb₂S₃,one of the most obvious was the RGO/Sb₂S₃-2.The degradation rate of Rh B could reach 96.33%under the 350 W xenon lamp irradiate for 280 min with the RGO/Sb₂S₃-1 as photocatalyst,and the good photocatalytic stability was confirmed by circulating photocatalytic experiments.In addition,it was confirmed that the·OH was the main active group in the photocatalysis process through TA-PL detection technology and the photocatalytic contral experiment of adding Vc.(3)The RGO/Bi₂S₃nanocomposites were successfully prepared by microwave method,using GO,BiCl₃,Tu(thiourea)and 1,2 propylene glycol as raw materials.The product was characterized by a series of methods.The results showed that the product was orthorhombic crystal system.FT-IR analysis showed that these-OH,-COOH and epoxy groups in GO could be reduced by reacting at 20%microwave power for 25min.The SEM analysis showed that when the GO concentration was 1.5 mg/m L,the product had the best composite effect.UV-Vis spectra analysis showed that the band gaps of RGO/Bi₂S₃-0.5 and Bi₂S₃were 1.57 e V and 1.67 e V respectively.The degradation rate of methylene blue(MB)could reach 91.13%under the 350 W xenon lamp irradiation for 200 min with the RGO/Sb₂S₃-1.5 as photocatalyst and the good photocatalytic stability was confirmed by circulating photocatalytic experiments.In addition,it was confirmed that the·OH was the main active group in the photocatalysis process through TA-PL detection technology and the photocatalytic contral experiment of adding Vc.