A Study On Preparation And Applications Of Cu Nanowires And Pt Coated Cu Nanowires

One-dimensional?1D?metal nanostructures are of considerable interest due to their different or superior optical,electrical,physical,catalytic and chemical properties comparing to bulk counterparts.Copper is probably the most freque ntly used metallic nanowire owing to their high earth abundance,unusual physical properties,such as superior thermal and electrical conductivity,and potential applications in nanodevices as interconnectors or as the candidate to replace traditional transparent electrodes indium tin oxide?ITO?.It is generally agreed that the properties of copper nanowires are mostly determined by their dimension,aspect ratio,structure and crystallinity.It has been demonstrated that the long copper nanowires with high aspect ratio and thin diameter conductor film possessed good transparency/conductivity performance by theoretical simulation and experimental results.Therefore,the crucial progress is that devoted facile methods to produce ultrathin copper nanowires.Fuel cells catalytic with high effective is always an important research topic,noble metal Pt is widely used as catalysts in electrochemical process,cause the high cost and low storage,many research devoted to enhance catalytic performance by design Pt structure and doped metallic.One dimension PtCu nanowires have peculiar superiority at direct methanol fuel cells due to it's structure and bimetallic.In present paper,High-quality and monodispersed copper nanowires with ultrathin and uniform diameters of 13.5 nm,length to 30?m were synthesized by a simple controllable hydrothermal reduction procedure by glucose in the presence of hexadecylamine?HDA?and octadecylamine?ODA?as the capping agent.Next we formed Pt/Cu nanowires by using Cu nanowires as template.The morphology and structure characteristic of Cu and Pt/Cu nanowires were measured using scanning electron microscopy?SEM?,transmission electron microscopy?TEM?,X-ray diffraction?XRD?and UV-visible spectrum.The transparent conductors of synthesized Cu nanowires were obtained to test transmittance and conductivity.Pt/Cu nanowires were obtained to test methanol electrocatalytic oxidation.The main conclusions are gained as follows.?1?To explore the formation of copper nanowires,copper ch loride dehydrate as metallic precursor and glucose as reductant,hexadecylamine?HDA?and octadecylamine?ODA?as capping reagent and the proper molar ratio HDA:ODA=0.4:0.8 could facilitated the ultrathin and homogeneous Cu nanowires formation.?2?To better understand the detailed structure and morphology of Cu nanowires at different reaction time,we acquired SAED,TEM and XRD pattern.We detected the penta-twinned structure and the growth direction?110?of nanowires.At the beginning of reaction,low surface energy{111}planes of penta-twinned nanoparticles are primarily product.With the increase of reaction temperature and time,more Cu?II?ions become Cu atoms and acquired thermodynamic energy,finally formed one-dimension nanowires.The final product HDA:ODA=0.4:0.8 shows the best conductivity,the conductor film from high-quality and ultrathin copper nanowires show high transmittance and low resistance?83.83%,61 ohms/sq??3?Composition controllable Pt/Cu nanowires were formed with reductant ascorbic acids introduced.The HClO₄ and CH₃OH solution electrocatalytic of Pt/Cu nanowires with different component were tested.Pt₁₄Cu₈₆6 nanowires demonstrated the highest ESCA 118.6 m²?g^-1,with the increase of Pt composition,the decrease of ESCA.Pt₅₉Cu₄₁ nanowires exhibited highest electrocatalytic 0.6018 A?mg^-1 and stability?current density residual 3.77%?.Pt₁₄Cu₈₆6 nanowires show the high ratio 5.54of positive sweep and anti-sweep,it demonstrated the Cu atoms in PtCu NWs can bonded with medium product of CO,reduce the poisoness of Pt and enhance the electrocatalytic.