Multiwalled carbon nanotubes/silver nanocomposite as effective SERS platform for detection of methylene blue dye in water

In this work, a functional nanocomposite consisting of silver nanoparticles and multiwalled carbon nanotubes (MWCNTs-Ag) was successfully synthesized using a two-step chemical process. The MWCNTs-Ag nanocomposite has been studied as a surface-enhanced Raman scattering (SERS) sensing platform for detection of methylene blue (MB) dye in an aqueous medium. The obtained results reveal that the MWCNTs-Ag nanocomposite exhibits higher SERS detection activity than that of pure Ag-nanoparticles (Ag-NPs). The calculated enhancement factors are 1.51 × 106 for pure Ag-NPs and 4.68 × 106 for the MWCNTs-Ag nanocomposite. MB detection has been achieved as low as 1 ppm. The SERS enhancement of the MWCNTs-Ag nanocomposite can be attributed to the combination of both an electromagnetic (EM) effect and a chemical effect (CE). With exhibited properties, the MWCNTs-Ag nanocomposite can be effectively used for detection of various organic dyes in water solution.