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Nanowires array of materials is one of the hotspots of nanoscience research, but also has a strong enhancement of surface-enhanced Raman spectroscopy (SERS) substrate. A substrate such as a study of great value to the study of SERS three research directions. DC chemical deposition, thermal decomposition method, solvothermal method, were prepared by a variety of new SERS substrate in the pores of anodic aluminum oxide (AAO) template. Lee and Meisel prepared gray silver plastic, to discuss the difference of the enhancement in the silver plastic before and after purification. In this paper, the main research work and conclusions: 1, the use of two-step oxidation Preparation of highly ordered AAO template, adjustable aperture. SEM showed that the bottom of the barrier layer of close-packed hexagonal structure. XRD showed that the template of the porous layer and the barrier layer are made of amorphous alumina. 2 times full range of current density - time (JT) the monitoring template preparation electrochemical polishing, oxidation to the oxide layer, an important process to block layer and through-hole. JT real-time monitoring of the experimental basis of the analysis template growth mechanism, the template quality control measures, optimize the preparation process of the evidence, to achieve a fine, precise control template preparation process of industrialization. 3, combined with the the DC deposition technique in the the secondary oxidation template with aluminum single-pass successfully prepared nickel nano-arrays. The XRD results show that the arrays prepared by the method of the polycrystal, and the diameter of the template aperture considerable. 4, the direct thermal decomposition of AgNO3, the growth of nano-silver in the template holes, template etched with a NaOH solution, an etching solution was centrifuged for separation, after ultrasonic dispersion, can be used as a SERS substrate, but the substrate is poor uniformity. 5 solvothermal growth of nano-silver, corrosion of the template in the template pores, after purification by centrifugation and ultrasonic dispersion, is the SERS substrate. The TEM results show that the nano-spherical particles, the particle size uniformity. If the template for a solvothermal reaction after annealing, the primary form of nano-silver nanowires, nanorods, the nanosphere particles. 6, melamine as a probe molecule, based on the AAO template by electrochemical deposition, thermal decomposition method, the Solvothermal the SERS substrate, using portable Raman spectroscopy SERS spectrum of studies, a variety of substrates enhancement factor: 0.7 * 104,1.25 * 103,2.6 * 104, the minimum detectable amount of: 1.78 * 10-7g, 1.1 * 10-6g, 1.2 * 10-8g. 7 to gray silver paste as SERS substrate, the minimum detectable amount of 6 * 10-12g, the enhancement factor of 3.7 * 106, the enhancement effect was significantly higher than the template prepared by SERS substrate, but poor nanoparticles homogeneity, reproducibility is bad. Gray silver plastic centrifugal purification, the minimum detectable amount to 1.1 * 10-12g, the enhancement factor of up to 108, has a good signal-to-noise ratio, reaching the level of detection of the sub-monolayer. If the combination of melamine in food extraction technology, the method is expected to become melamine in food fast, on-site, accurate means of detection.
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