Preparation of ZnO/Ag nanoflowers by hydrothermal assisted with galvanic effect and its surface enhanced Raman scattering activity

An effective approach is proposed for fabrication of ZnO/Ag nanocomposite for surface enhanced Raman scattering application by combining hydrothermal assisted with galvanic effect and sputtering process. The sputtering process is applied to distribute Ag on the surface of ZnO nanostructures. The morphology, structure, elemental composition and optical properties of the samples were studied. The most suitable sputtering condition was identified to achieve the highest Raman enhancement. The optimum sputtering time of 70 s provides strong Raman signal of methylene blue, and demonstrates the potential of using the ZnO/Ag nanoflowers as sensitive surface enhanced Raman substrates.