Large Area Few-Layer Hexagonal Boron Nitride as a Raman Enhancement Material

Area of Science:

• Materials Science
• Spectroscopy
• Nanotechnology

Background:

• Two-dimensional (2D) materials are explored for surface-enhanced Raman spectroscopy (SERS).
• Hexagonal Boron Nitride (hBN), a graphene analogue, is typically used in nanoelectronics.
• hBN's SERS activity remains less explored.

Purpose of the Study:

• Investigate the SERS activity of few-layer hBN films.
• Evaluate hBN as a SERS-active substrate.
• Determine the stability and versatility of hBN for SERS.

Main Methods:

• Synthesized few-layer hBN films on copper foil via chemical vapor deposition.
• Applied probe molecules (malachite green, methylene blue, rhodamine 6G) via drop casting.
• Measured SERS enhancement using a 532 nm laser.

Main Results:

• Achieved SERS enhancements of ~10^3 for malachite green and ~10^4 for methylene blue and rhodamine 6G.
• Observed enhancement factors correlate with calculated interaction energies.
• Enhancement was independent of film thickness and surface morphology.
• Demonstrated high stability, with similar enhancements from films aged 7 months.

Conclusions:

• Few-layer hBN films are effective SERS substrates.
• hBN exhibits versatility and durability for SERS applications.
• hBN presents a promising alternative to traditional SERS materials.