Synthesis And Catalytic Performance Of Two-dimensional Gold Nanoparticles/Graphene Oxide Composite Materials

The physical and chemical properties of noble metal nanoparticles are closely related to their morphology.Due to the special anisotropic structure of two-dimensional gold nanoparticles(such as gold nanoring,gold nanoplate,etc.)and their superior properties in optical and electrical,they have good application prospect in the fields of biological sensing,surface enhanced Raman scattering(SERS)and so on.Graphene oxide is a derivative of graphene,it has the characteristics of high specific surface area and high electrical conductivity.Also,its surface is full of oxidation functional groups,it can be used as an ideal carrier for nanoparticles to stabilize and disperse them.Moreover,the synergetic effect between graphene oxide and metal nanoparticles can further improve their catalytic performance.Investigating a strategy which could synthesis two-dimensional gold nanoparticles/graphene oxide composites with controllable morphology and good dispersion has become the focus of research.The main contents of this paper are as follows:(1)Silver nanoparticles/graphene oxide composites were prepared by chemical in-situ reduction method using silver nitrate and graphene oxide as raw materials.TEM results showed that the inner diameter of as-prepared gold nanorings are in the range of80~120nm,the lattice structure is neat,and the gold nanorings can be evenly distributed on the surface of graphene oxide.The EDX data indicated the elemental composition of the composite.The XRD spectra showed that the gold nanorings are face-centered cubic structure based on Au{111}plane,and the Raman spectra indicated that graphene oxide and metal ions are reduced at the same time.Also the oxygen-containing groups on the surface of graphene oxide decreased obviously.(2)Gold nanoparticles/graphene oxide composites were prepared by seed growth method and solution reduction method respectively,using chloroauric acid and graphene oxide as raw materials.According to the test results of SEM and TEM,it is obvious that:triangular gold nanoparticles with particle size in the range of 50~100nm can be prepared by solvent reduction method,and the yield is higher.(3)Reduction of 4-nitrophenol by sodium borohydride was used as a template reaction.The as-prepared materials are used as catalysts,they can efficiently catalyze the degradation of 4-nitrophenol.The kinetic constants of the gold nanoring/graphene oxide composite materials were up to 0.205min~-11 by fitting the data measured by UV-vis spectroscopy.Figure[34]table[6]reference[107]...