Abstract：Recently, Surface Enhanced Raman Scattering (SERS) has attracted much attention due to its advantages innondestructive, ultra-sensitive and rapid detection analysis. It has great potential in chemical and biological sensing applications. SERS substrates with high sensitivity, repeatability and stability are of great significance to the application in trace analysis and biological diagnosis. Polymer materials with micro/nanostructure have excellent mechanical and optical properties and chemical resistance. In this work, a highly ordered polycarbonate (PC) nanocone array was fabricated by template imprinting on the surface of PC using porous anodic alumina (AAO). Then a silver film was deposited on the nanocone array by thermal evaporation technology, and alarge area of ordered polymer nanocone array modified by Ag nanoparticles was prepared. A large number of SRES “hot spots” can be generated by the narrow nano-gap between silver particles and particles at the top of the high curvature nano-needle structure. SERS active substrates with uniform, repeatable, large area and high enhancement were obtained by this method. The SERS characteristics of silver films with different thickness were further studied. Scanning electron microscopy (SEM) was used to characterize the structure. Crystal violet was used as a probe molecule in this study. The results show that the intensity of Raman signal increases first and then decreases with the increase of silver thickness. The Raman enhancement factor is of ~5.4×106, and the RSD of the main Raman peak intensity of CV is 10%, indicating good sensitivity and repeatability. In addition, after 40 days storage, the substrate still maintained high SERS performance under the same conditions, showing good stability. The whole preparation process is simple, reproducible, very cheap, and can be prepared on a large scale. It can be easily used as an active substrate for SERS research, and will have broad research and application prospects.
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