Synthesis And Photoelectronic Characterization Of Metal Nanostructures

In this paper, we reported a solid state ionics method to synthesize silver and copper nanostructures by employing solid electrolyte film under a direct current electric field. Controlled synthesis of metal nanostructures of different morphologies could be achieved by controlling the solid electrolyte film and experimental conditions. The growing process of metal nanowires was observed in real time in suit SEM for the first time, and the mechanism of this synthesis has been investigated. Benefiting from the fully understanding of this method, experimental conditions have been improved and well aligned high quality metal nanowire arrays of macroscopic scale have been prepared. Their photoelectrical properties were systemically investigated.When we employ silver films as electrodes and RbAg4I5 film as the medium for the transmission of silver ions, by controlling the electric field strength, silver nanostructures with different morphologies, such as nanowie arrays, nanotube arrays and nanopartical arrays, could be prepared. The arrangement of the nanowires could also be artificially controlled. When we employ copper films as electrodes and different medium films for transmitting copper ions, copper nanostructures with different morphologies were prepared. The relationship between the morphology of nanostructures and the experimental conditions, such as the growing temperature and the electric field strength, has been investigated.The growing process of silver nanowires was observed in real time in suit SEM, and the"tip effect"mechanism was disclosed. The relationship between the morphology of nanostructures and the electric field strength has been investigated in real time. Benefiting from the fully understanding of the solid state ioncs method, well aligned silver and copper nanowire arrays of centimeter scale were firstly synthesized when constant electric current was employed. Their morphologies and structures were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and high-resolution transmission electron microscopy (HRTEM). The I-V curves and the temperature-dependence of resistivity were measured by the four-terminal method, results show that the temperature coefficient of the nanowires is much smaller than that of the bulk metal. The photoelectric response of the heterjunction was investigated by a 532 and a 10600 laser. The conception of the heterodimension homojunction was raised for the first time. Experiments show that the photoinduced current of the heterodimension homojunction as a linear function of the laser power. What is more, the transport direction of photoexcited electrons is from low dimension nanowires to the nearest bulk electrode. Photosensitive properties of copper nanowires coated by copper oxide were investigated. Silver nanowire arrays were used as the surface-enhanced Raman scattering substrate to detect Raman spectrum of R6G solution. The relationship between the arrangement and density of the nanowires with the enhanced efficacy was investigated.