One-step synthesis of Ag₂S/Ag@MoS₂ nanocomposites for SERS and photocatalytic applications

This paper reported a one-step synthesis of Ag₂S/Ag@MoS₂ nanocomposites and its applications in the surface-enhanced Raman scattering (SERS) detection and photocatalytic degradation of organic pollutants. The nanocomposites were well characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), cyclic voltammograms (CV), the Brunauer-Emmett-Teller (BET), and Fourier transforms infrared spectra (FTIR). The AgNPs were uniformly dispersed on the MoS₂ nanosheets and the particle size of the AgNPs was about 10–30 nm. These Ag₂S/Ag@MoS₂ nanocomposites offered sensitive SERS signals for the detection of R6G with the limit of detections as low as 10⁻¹⁰ M. The photocatalytic activity of the composite catalyst was studied by the degradation of methylene blue (MB) dye under light illumination. The apparent rate constant of MB degradation for the obtained catalyst could reach 6.6 × 10⁻² min⁻¹, indicating that the novel Ag₂S/Ag@MoS₂ nanocomposites can be explored for organic pollutant's detection and degradation.