A simple way to synthesize large-scale CuO/Ag nanoflowers for ultrasensitive surface-enhanced Raman scattering detection.

Here, we report a simple strategy to prepare highly sensitive surface-enhanced Raman spectroscopy (SERS) substrates based on Ag decorated CuO nanoparticles by combining two common techniques, viz, thermal oxidation growth of CuO nanoparticles and magnetron sputtering fabrication of a Ag nanoparticle film. Methylene blue is used as the Raman analyte for the SERS study, and the substrates fabricated under optimized conditions have very good sensitivity (analytical enhancement factor ∼10), stability, and reproducibility. A linear dependence of the SERS intensities with the concentration was obtained with an R value >0.9. These excellent properties indicate that the substrate has great potential in the detection of biological and chemical substances.