Annealing Temperature-Dependent Surface-Enhanced Raman spectroscopy on MoS₂-Covered silver nanoparticle array.

Area of Science:

• Materials Science
• Nanotechnology
• Analytical Chemistry

Background:

• Surface-enhanced Raman spectroscopy (SERS) offers ultra-sensitive molecular detection via vibrational fingerprints.
• Developing stable, sensitive, and reproducible SERS substrates remains a significant challenge for practical applications.
• Two-dimensional (2D) materials combined with metallic nanostructures present a promising avenue for enhancing SERS performance.

Purpose of the Study:

• To fabricate and characterize a high-performance SERS substrate using a monolayer molybdenum disulfide (MoS2) covered silver nanoparticle (AgNP) array.
• To investigate the effect of annealing temperature on the SERS performance of the MoS2/AgNPs hybrid substrate.
• To evaluate the potential applications of the developed substrate in food safety and biochemical environmental detection.

Main Methods:

• Fabrication of a hybrid SERS substrate comprising a monolayer MoS2 film and an array of AgNPs.
• Systematic exploration of annealing temperature effects on SERS signal intensity and substrate performance.
• Characterization of substrate morphology, nanoparticle distribution, and contact interface using relevant techniques.

Main Results:

• Optimal SERS performance was achieved at an annealing temperature of 290 °C.
• The optimized substrate exhibited a detection limit of 10⁻¹³ M for Rhodamine 6G with a SERS enhancement factor of 8.3 × 10⁹.
• Enhanced performance is attributed to improved AgNP-MoS2 contact and uniform AgNPs with optimal particle size.

Conclusions:

• The MoS2/AgNPs hybrid substrate demonstrates superior sensitivity, stability, and reproducibility for SERS applications.
• The optimized annealing process is crucial for maximizing the SERS enhancement.
• The developed substrate shows significant potential for sensitive detection in food safety and environmental monitoring.