Synthesis And Stirring-assisted Assembly Of Silver Nanowires

Nanomaterials have attracted much attention because of their unique microstructure. As a kind of one-dimensional nanomaterial, silver nanowire has good antibacterial property, electrical conductivity, catalytic performance and biocompatibility, so it is widely used in many fields. In this paper, we developed a method to prepare silver nanowires rapidly in large scale. And then, we fabricated a soft transparent electrode successfully by using the silver nanowires we got in this method. The detailed work include:Firstly, in a classic ethylene glycol system, in the presence of PVP, CuCl2·2HO and Cu(NO3)2-3H2O, large-scale uniform silver nanowires with high aspect ratio were rapidly prepared within 3-5 minutes through a two-step addition of high-concentration AgNO3 solution. Then many factors influenced the preparation are studied in this paper, including the influence of Cu2+, Cl-, the pattern and volume of AgNO3 solution added to the reaction system in the first step, and the addition of Cu(NO3)2-3H2O. Silver nanowires synthesized by this method were tested by SEM, UV, XRD and TEM. The length can be up to 100 μm, when the diameter of the silver nanowires in this method is about 93 nm. The aspect ratio can be up to 1000. The yield of this method in a single production increased to 1.08 g form the usual 100-200 mg. The reaction time is shorted from 1-4 hours to 3-5 minutes, which is benefit to improve the efficiency of the synthesis and to promote the mass production in the future.Then, a bilayer cross orderly film of silver nanowires was fabricated on a flexible PDMS substrate by using the shearing force produced by stirring as the driving force. We discussed a variety of factors which influenced the assembly, including how to decorate the flexible PDMS substrate, the stirring time and rates. And then, SEM, UV and multimeter were employed to test the morphology, transmittance and electrical conductivity respectively after the assembly. As study proved, we can fabricate silver nanowire film with high degree of order and transmittance by using this method. The assembly method is not only simple, universal, but largely saved the cost of manufacturing a electrode.