Nanoscale characterization of plasma functionalized graphitic flakes using tip-enhanced Raman spectroscopy

Area of Science:

• Materials Science
• Nanotechnology
• Chemistry

Background:

• Chemical functionalization of graphene nanomaterials is key for advanced applications.
• Precisely quantifying functional groups on individual graphene nanoplatelets is difficult.
• Understanding functionalization's spatial distribution is crucial for property control.

Purpose of the Study:

• To demonstrate tip-enhanced Raman spectroscopy (TERS) for nanoscale analysis of graphene functionalization.
• To investigate the degree and spatial variability of disorder in nitrogen-functionalized graphitic nanomaterials.
• To correlate TERS findings with other analytical techniques for comprehensive characterization.

Main Methods:

• Tip-enhanced Raman spectroscopy (TERS) was employed to analyze graphene.
• Three distinct levels of nitrogen functionalization were studied.
• TERS data was validated against confocal Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectrometry (ToF-SIMS).

Main Results:

• TERS successfully mapped the nanoscale distribution of disorder in functionalized graphene.
• Results showed excellent agreement between TERS and conventional spectroscopic/chemical analysis methods.
• The study quantified the degree and spatial variability of nitrogen functionalization.

Conclusions:

• TERS is a powerful tool for nanoscale characterization of graphene functionalization.
• This work improves understanding of graphene functionalization across multiple scales (nano, micro, macro).
• The findings facilitate the correlation between functionalization, analytical techniques, and material properties of industrial relevance.