Fabrication Of Ag Nanowires Films And Their Application For Electrochemical Sensors

Since nanomaterials were found, nanomaterials have attracted more and more attention because of their all kinds of properties which originate from their unique microstructure. As one of the nanomaterials, silver nanowires have good electrical conductivity, antibacterial property, catalytic performance and biocompatibility, so silver nanowires are used in many fields. To promote the applications of silver nanowires, it is important to develop the technology of synthesis and assembly. And entensive research about the properties of silver nanowires is also very important to broaden the applied range of silver nanowires and make silver nanowires used in a large scale.In this paper, a systematic study was done about the preparation, assembly and application of the silver nanowires. At first silver nanowires were synthesized efficiently by the polyol method, and then silver nanowires were assembled in a flow field by using the shearing force produced by stirring as the driving force for the first time, at last by the assembly technology with stirring a new AgNWs/GCE sensor used for the detection of H2O2 was fabricated to study the application of the technology assembled by stirring and the silver nanowires. The detailed works include:Firstly, silver nanowires with high selectivity and high aspect ratio were synthesized by the self-seeding method, the influence of oxygen and the dropping speed have also been investigated. After optimized the parameters, the synthetic efficiency and repeatability of silver nanowires were improved by adding NaCl as a control agent. Silver nanowires synthesized were tested by SEM, UV and XRD.Silver nanowires were assembled in different solutions and different substrates by using the shearing force produced by stirring as the driving force for the first time, and we also investigated the affect of stirring and the different side of the substrate film. We found this method not only effective but also cause directivity, this progress was also tested and proved by SEM.By the assembly technology with stirring a new AgNWs/GCE sensor used for the detection of H2O2 was fabricated. we found the respond speed of the new detector is fast enough to reach the 95% of the steady-state current within 4 s, besides of that the reduction current of detector shows a good linear characteristic with concentration in the range of 0.50～14.69 mmol/L and 16.62～79.60 mmol/L, the detection limit of the sensor is 0.50 mmol/L(s/n=3) and the sensor was tested to show having good selectivity and reproducibility, which all proved that the new sensor assembled by stirring shows good electro-catalysis performance. we not only used SEM to investigate the morphology of the surface of the electrode, but also used cyclic voltammetry and current-time curve to demonstrate the electrochemical performance of the sensor.