(Cu₂O-Au) - Graphene - Au layered structures as efficient near Infra - Red SERS substrates

Area of Science:

• Materials Science
• Spectroscopy
• Nanotechnology

Background:

• Conventional Surface Enhanced Raman Spectroscopy (SERS) using visible light is hindered by strong fluorescence, masking weak Raman signals.
• Near Infra-Red Surface Enhanced Raman Spectroscopy (NIR SERS) offers a solution by overcoming fluorescence interference.
• Development of efficient NIR SERS substrates is crucial for sensitive chemical detection.

Purpose of the Study:

• To design and simulate a novel multi-layered SERS substrate for enhanced NIR SERS performance.
• To optimize the plasmonic properties of core-shell nanoparticles for NIR applications.
• To demonstrate the potential of the designed substrate for sensitive NIR SERS detection.

Main Methods:

• Utilized Mie simulations with MieLab software to optimize core-shell nanoparticle aspect ratios for NIR plasmon resonance.
• Employed Finite Difference Time Domain (FDTD) simulations using Lumerical software for multi-particle layered substrate design.
• Investigated a (Cu2O-Au)-Graphene-Au layered structure on an Au substrate with a graphene spacer.

Main Results:

• Optimized core-shell particles exhibited plasmon resonances in the NIR region.
• The designed multi-layered substrate achieved a high field enhancement factor of approximately 10^8 at 1064 nm excitation.
• Simulations confirmed the substrate's potential for efficient NIR SERS applications.

Conclusions:

• The proposed (Cu2O-Au)-Graphene-Au multi-layered structure is a promising candidate for efficient NIR SERS.
• This novel substrate design can overcome fluorescence limitations and enhance Raman signal detection in the NIR region.
• The developed substrate holds potential for various advanced NIR sensing applications.