Controlled Synthesis And Catalytic Performance Of Au-pearl/Pd-wire Heterostructure Nanonecklace

Noble metal nanomaterials show enormous research and application potential in the areas such as catalytic reaction and biosensing etc.The properties of noble metal nanomaterials are affected by the morphology and structure,in this respect,controlled synthesis of noble metal nanomaterials has great significance.Heterostructure have received great attention due to the superior performance they have.In this paper,we focus on the controlled synthesis of Pd-Au heterostructured nanomaterial which made up of numbers of regular Au-Pearls stringed by ultrathin and ultralong Pd-wire.We also studied the relationship between the catalytic activity and the morphology of this kinds of nanomaterial.The main work contens are as follow:1.By using the ultrathin and ultralong Te nanowires as the sacrificed template,under certain reaction condition,the interval and size of Au nanopearls on the Au-pearl/Pd-wire heterostrctured nanonecklaces could be regulated by simply adjusted the amount of reductant.In this paper,multiple characterization analysis have been used on the synthesized materials,including: TEM,HRTEM,HAADF-STEM etc.We also demonstrated the quantitative relation between the amount of reductant and the interval/size of Au pearls while the amount of Au precursor is fixed: the distribution density of Au nanopearls was regulated by the concentration of reducing agent,while their size was controlled by the amount of Au precursor.The forming process of the Au-pearl/Pd-wire heterostrctured nanonecklaces has also been disgussed.2.In this paper,the catalytic ability of Pd-Au nanonecklaces for the reduction reaction of methyl orange,methylene blue and 4-nitrophenol has been studied.Firstly,we tested the catalytic ability of Pd-Au nanonecklaces with different Au nanopearls' size and interval,and compared it with Pd Au nanowires,Pd nanowires,Au nanoparticles and Pd nanowires mixed with Au nanoparticles.The results showed the Pd-Au heterostructured nanonecklace exhibited higher catalytic activity and durability than the control group.And as the morphology changed the catalytic ability of Pd-Au nanonecklaces had also been altered.When the interval and size of Au nanopearls increases in certain content,the material shows better catalytic ability.