A gold-silver nanostar 2D array composite structure for rapid SERS determination of PAHs

Area of Science:

• Environmental Science
• Materials Science
• Analytical Chemistry

Background:

• Polycyclic aromatic hydrocarbons (PAHs) are significant environmental pollutants.
• Accurate and sensitive detection of PAHs in water is crucial for environmental monitoring.
• Existing detection methods can be complex or lack portability.

Purpose of the Study:

• To develop a portable detection tool for PAHs in water samples.
• To utilize a novel dual-metal surface-enhanced Raman scattering (SERS) substrate for enhanced sensitivity.
• To assess the stability and detection limits of the developed SERS platform.

Main Methods:

• Synthesis of gold-silver nanostars (AuNS@Ag) via a secondary seed-mediated growth method.
• Assembly of AuNS@Ag into a 2D array using liquid-phase interface self-assembly on a silicon wafer.
• Detection of PAHs in water samples using a portable Raman spectrometer coupled with the AuNS@Ag SERS substrate.

Main Results:

• The dual-metal SERS substrate demonstrated high sensitivity and stability.
• Detection limits for pyrene and phenanthrene were achieved at 10^-8 M and 0.5 × 10^-8 M, respectively.
• The portable detection tool successfully identified PAHs in water samples.

Conclusions:

• The developed portable PAH detection tool based on the AuNS@Ag 2D SERS array is highly effective.
• The SERS platform exhibits excellent sensitivity, stability, and potential for real-time environmental monitoring.
• This technology offers a promising solution for the on-site detection of PAHs in aquatic environments.