Chemical Analysis of Commercial Functionalized Graphene Nanoplatelets along the Production Process with Raman...

Area of Science:

• Materials Science
• Nanotechnology
• Surface Chemistry

Background:

• Commercial applications utilize functionalized graphene nanoplatelets (GNPs) in various forms.
• Understanding the process-structure-property relationships of GNPs is crucial for industrial applications.
• Current knowledge gaps exist in mapping these relationships across the production chain.

Purpose of the Study:

• To establish a comprehensive understanding of graphene nanoplatelets' (GNPs) structure-property relationships.
• To link GNP functionalization and formulation to their lattice disorder and surface chemistry.
• To develop transferable quality-control metrics for industrial graphene supply chains.

Main Methods:

• Correlative Raman spectroscopy (Raman) and X-ray photoelectron spectroscopy (XPS) workflow.
• Analysis of nine industrial graphene batches with three surface chemistries (raw, fluorinated, nitrogen-functionalized) and three physical forms (powders, suspensions, inks).
• Raman mapping and high-resolution XPS for detailed structural and chemical characterization.

Main Results:

• Raman mapping indicated highest I_2D/I_G for nitrogen-functionalized (N) samples and lowest for raw (R) ink.
• Point defect spacing (L_D) was determined to be 8.4-10.0 nm across samples.
• XPS revealed distinct chemical changes, including loss of fluorine content upon dispersion and ink formulation, and presence of ink-specific O-C O and C-N peaks.

Conclusions:

• A process-aware blueprint was established, connecting functionalization and formulation to GNP lattice disorder and surface chemistry.
• Quality-control metrics for industrial graphene supply chains were proposed.
• The findings support the use of functionalized GNPs in coatings, storage devices, and printed electronics.