کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1229796 | 1495217 | 2016 | 7 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Nanocap array of Au:Ag composite for surface-enhanced Raman scattering Nanocap array of Au:Ag composite for surface-enhanced Raman scattering](/preview/png/1229796.png)
• The co-sputtering Au:Ag bimetal array formed the protrusion network of Ag and Au nanoparticles.
• The metal protrusions in the waxberry-like shell contribute to the Raman enhancement.
• The SERS enhancements show the strong gap size-dependent behaviors.
We fabricated Au:Ag nanocap arrays by co-sputtering Au and Ag onto two-dimensional polystyrene (PS) colloidal sphere templates in a magnetron sputtering system for the surface-enhanced Raman scattering (SERS) substrate. In contrast to the bilayer Au/Ag, the co-sputtering Au:Ag bimetal array formed the protrusion network of Ag and Au nanoparticles, which contributed to Raman enhancement in the waxberry-like structure. The metal protrusions formed waxberry-like shell in which the PS beads were encapsulated. At the same time, the Au:Ag bimetal arrays exhibit 4-fold more enhancement in the SERS signal intensity of Rhodamine 6G at the 1649 cm−1 than Au/Ag bilayer array, which is ascribed to the plasmon coupling between the nanoparticles of Au and Ag on the sample. When the PS colloidal particle templates were etched by O2-plasma before sputtering process, the nanogaps affected the surface plasmon resonance (SPR), and the optimal gaps between adjacent Au:Ag nanocaps generated even stronger SERS enhancements. This SERS substrate of Au:Ag showed high sensitivity and reproducibility. The EF of Au:Ag nanocap array substrate onto which Rhodamine 6G (R6G) were adsorbed was evaluated as 6.72 × 1010.
In comparison to the curved Au/Ag bilayer, the Au:Ag bimetal arrays exhibit 4-fold more enhancement when Rhodamine 6G is chosen as the probing molecule.Figure optionsDownload as PowerPoint slide
Journal: Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy - Volume 152, 5 January 2016, Pages 461–467