SERS-active Ag/Au bimetallic nanoalloys on Si/SiO(x)

Area of Science:

• Materials Science
• Nanotechnology
• Spectroscopy

Background:

• Nanoalloys, composed of two or more metallic elements, are crucial for applications in catalysis, spectroscopy, photonics, electronics, and magnetism.
• The hybridization of plasmonic absorptions in alloyed metals enables tunable plasmon resonances.
• This tunability enhances the performance of surface-enhanced Raman scattering (SERS) spectroscopy.

Purpose of the Study:

• To develop simple fabrication procedures for silver-gold (Ag/Au) nanoalloys on silicon/silicon oxide (Si/SiO(x)) substrates.
• To achieve tunable plasmon resonances in the fabricated Ag/Au nanoalloys.
• To investigate the formation mechanism, kinetics, and optical properties of these nanoalloys for SERS applications.

Main Methods:

• Fabrication of Ag/Au nanoalloys on Si/SiO(x) substrates.
• Characterization using Scanning Electron Microscopy (SEM) to analyze morphology.
• X-ray Photoelectron Spectroscopy (XPS) for surface composition analysis.
• Surface Plasmon Resonance (SPR) and SERS spectroscopy to study optical properties and enhancement factors.

Main Results:

• Successful fabrication of Ag/Au nanoalloys with tunable plasmon resonances.
• Demonstrated significant increases in the enhancement factor for SERS.
• Detailed understanding of the nanoalloy formation mechanism and kinetics.

Conclusions:

• Simple fabrication methods yield Ag/Au nanoalloys with tunable optical properties.
• These nanoalloys are highly effective for enhancing SERS signals.
• The study provides a foundation for utilizing Ag/Au nanoalloys in advanced spectroscopic techniques.