Porous gold nanodisks with multiple internal hot spots

Area of Science:

• Nanotechnology
• Materials Science
• Chemistry

Background:

• Plasmonic nanoparticles are crucial for surface-enhanced Raman spectroscopy (SERS).
• Increasing internal hot spots in nanoparticles enhances SERS signal intensity.
• Existing methods for creating hot spots have limitations.

Purpose of the Study:

• To develop a novel method for synthesizing porous gold nanostructures with numerous internal hot spots.
• To enhance the sensitivity of SERS detection using these engineered nanostructures.
• To explore the potential of porous plasmonic nanodisks as molecular imaging agents.

Main Methods:

• A hybrid approach combining physical patterning and chemical nanopore formation was used.
• Lithography was employed to design gold nanodisks with specific shapes and dimensions.
• Numerical electromagnetic simulations were performed to understand the SERS enhancement mechanism.

Main Results:

• Porous gold nanodisks with internal nanopores, acting as Raman hot spots, were successfully synthesized.
• The number of internal hot spots was significantly increased compared to non-porous counterparts.
• SERS intensity was substantially improved and showed high homogeneity.
• Experimental results were consistent with electromagnetic simulations.

Conclusions:

• The developed hybrid approach enables the fabrication of porous plasmonic nanodisks with enhanced SERS capabilities.
• These nanostructures serve as effective SERS substrates with improved sensitivity and homogeneity.
• Porous plasmonic nanodisks hold significant promise for applications in sensitive molecular imaging.