Silver Nanoparticle-Decorated Shape-Memory Polystyrene Sheets as Highly Sensitive Surface-Enhanced Raman Scattering...

Area of Science:

• Materials Science
• Nanotechnology
• Analytical Chemistry

Background:

• Surface-enhanced Raman scattering (SERS) is a powerful technique for detecting molecules at low concentrations.
• Developing stable and sensitive SERS substrates with tunable properties remains a key challenge.
• Shape-memory polymers offer unique possibilities for creating dynamic nanostructures.

Purpose of the Study:

• To fabricate an active SERS substrate with a thermally inducible hot spot effect.
• To investigate the influence of nanoparticle spacing on SERS enhancement.
• To evaluate the substrate's suitability for quantitative analysis of Raman-active molecules.

Main Methods:

• Decoration of n-octylamine-pretreated shape-memory polystyrene (SMP) sheets with silver nanoparticles (AgNPs).
• Optimization of AgNP decoration conditions to control particle gaps and create inducible hot spots upon thermal shrinkage.
• Characterization of SERS performance using aromatic thiols and quantitative analysis of adenine.

Main Results:

• Fabrication of AgNP-decorated SMP (Ag@SMP) substrates exhibiting thermally inducible hot spot effects.
• Achieved SERS enhancement factors exceeding 10^8 for aromatic thiols.
• Demonstrated high suitability for quantitative analysis with a low limit of detection (120 pg/cm^2) and excellent linearity (R^2=0.9959).
• Exhibited high reproducibility with a relative standard deviation below 10%.

Conclusions:

• The developed Ag@SMP substrate effectively utilizes a thermally inducible hot spot effect for sensitive SERS measurements.
• AgNP spacing is critical for maximizing hot spot generation and SERS enhancement.
• The substrate demonstrates excellent potential for sensitive and reproducible quantitative SERS analysis.