Gold nanoparticle thin films fabricated by electrophoretic deposition method for highly sensitive SERS application

Area of Science:

• Nanotechnology
• Materials Science
• Analytical Chemistry

Background:

• Surface-enhanced Raman scattering (SERS) requires sensitive substrates for detecting low analyte concentrations.
• Gold nanoparticles (GNPs) are promising for SERS due to their strong localized surface plasmon resonance (LSPR).
• Fabrication methods for uniform and high-density GNP films are crucial for SERS applications.

Purpose of the Study:

• To develop an efficient electrophoretic deposition method for fabricating gold nanoparticle (GNP) thin films.
• To investigate the relationship between GNP deposition density and SERS performance.
• To demonstrate the potential of these GNP films as sensitive SERS substrates.

Main Methods:

• Synthesized GNP sol using a seed-mediated growth approach.
• Utilized electrophoretic deposition with GNP sol and indium tin oxide (ITO) glass electrodes.
• Analyzed GNP film morphology using scanning electron microscopy (SEM).
• Evaluated SERS sensitivity using rhodamine 6G in methanol solution.

Main Results:

• GNP deposition density on ITO substrates increased with electrophoresis time.
• Fabricated GNP films exhibited high mechanical adhesion strength.
• The films showed strong LSPR effects and high SERS sensitivity for detecting 1 × 10⁻⁷ M rhodamine 6G.
• Higher GNP density correlated with greater Raman signal amplification.

Conclusions:

• Electrophoretic deposition is an effective method for fabricating GNP thin films for SERS.
• GNP film density significantly influences SERS signal amplification.
• These GNP films are highly sensitive and suitable for SERS-based detection.