This paper presents a highly-ordered metallic nanotube array (MeNTA) coated with graphene oxide (GO) to serve as a surface-enhanced Raman scattering (SERS) substrate. The MeNTA was fabricated using a top-down wafer-scale lithographic and sputter-deposition process, after which a thin layer of GO was deposited uniformly via dip coating. Scanning electron microscopy revealed that GO dip coating did not mar the highly ordered periodic structures on the MeNTA substrate. Raman scattering spectra of Rhodamine 6G (R6G) molecules revealed that coating MeNTA substrates with GO enhanced peak intensity by as much as 2.9 times. Among the substrates examined in this study, the Ag GO MeNTA presented the strongest SERS behavior, with a detection limit of 10−8 M and enhancement factors of 5.38 × 105 for R6G and 2.23 × 105 for Crystal Violet (CV). The uniform distribution of GO and array of periodic structures returned highly consistent (i.e., reproducible) analyte Raman signals, with a relative standard deviation of 12.7 % for R6G and 9.3 % for CV and excellent linear relationship between Raman signal intensity and analyte concentration (R2 = 0.9974 for R6G, 0.9844 for CV).
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