Optimum fabrication parameters for preparing high performance SERS substrates based on Si pyramid structure and...

Area of Science:

• Materials Science
• Nanotechnology
• Spectroscopy

Background:

• Surface-Enhanced Raman Scattering (SERS) requires optimized substrate structures for enhanced sensitivity.
• Developing cost-effective and high-performance SERS substrates is crucial for widespread application.

Purpose of the Study:

• To propose simple and inexpensive methods for preparing micro/nano hierarchical SERS substrates.
• To optimize the structure of silicon micro-pyramids and silver nanoparticles for maximum SERS enhancement.
• To evaluate the SERS performance for detecting trace amounts of abamectin.

Main Methods:

• Fabrication of silicon micro-pyramid arrays via anisotropic wet etching.
• Deposition of silver thin films and subsequent annealing to form silver nanoparticles (AgNPs).
• Optimization of etching temperature, silver film thickness, and etching time.

Main Results:

• Optimized substrates with silver nanoparticles (42-48 nm) on silicon micro-pyramids (7-10 μm base-edge).
• Strongest plasmonic effect observed with a 30 nm silver film thickness.
• Achieved an enhancement factor of 1 × 10^6 for abamectin detection.
• SERS detection limit for abamectin as low as 5.7 × 10^-9 M.

Conclusions:

• A novel, cost-effective micro/nano hierarchical SERS substrate has been successfully developed.
• The optimized substrate demonstrates excellent sensitivity and potential for trace molecule detection.
• This SERS substrate holds promise for applications in medicine, biotechnology, and food security.