Exfoliating two-dimensional materials into few layers via optimized environmentally-friendly ternary solvents

Area of Science:

• Materials Science
• Nanotechnology
• Physical Chemistry

Background:

• Exfoliation of 2D materials is crucial for their applications.
• Conventional solvents (e.g., DMF, NMP) for 2D material dispersion are toxic and non-volatile.
• Need for safer, effective exfoliation methods.

Purpose of the Study:

• To design and utilize less toxic, volatile solvent mixtures for 2D material exfoliation.
• To demonstrate effective exfoliation of reduced graphene oxide (rGO) and black phosphorus (BP).
• To explore the role of surfactants in enhancing dispersion.

Main Methods:

• Application of Hansen solubility parameters theory for solvent mixture design.
• Use of polyvinylpyrrolidone (PVP) as a surfactant to functionalize rGO.
• Characterization of exfoliated 2D materials (rGO and BP).

Main Results:

• Designed solvent mixtures enabled excellent exfoliation and dispersion of 2D materials.
• Polyvinylpyrrolidone (PVP) effectively functionalized graphene.
• Few-layer rGO and BP (2-3 nm thickness) were successfully obtained.

Conclusions:

• The developed solvent mixtures offer a safer alternative to toxic solvents for 2D material exfoliation.
• The strategy is effective for producing high-quality, few-layer reduced graphene oxide and black phosphorus.
• This approach advances sustainable methods in 2D material processing.