Temperature as a key parameter for graphene sono-exfoliation in water

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Graphene dispersions in water are crucial for applications like biomedicine and coatings.
• Scalable, green production of graphene remains a significant challenge.
• The impact of processing liquid temperature on graphene exfoliation is often overlooked.

Purpose of the Study:

• To determine optimal temperature and power for sonication-assisted liquid phase exfoliation (LPE) of graphite in water.
• To characterize the quality and stability of graphene produced under optimized conditions.
• To establish temperature control as a critical factor for scalable graphene production.

Main Methods:

• Sonication-assisted liquid phase exfoliation (LPE) of graphite in aqueous solutions.
• Systematic characterization using UV-vis spectroscopy, Raman microscopy, and transmission electron microscopy (TEM).
• Acoustic pressure field measurements at various temperatures and input powers.

Main Results:

• High-quality few-layer graphene flakes were produced in pure water at 40°C and 50% input generator power within 2 hours.
• UV-vis analysis indicated improved exfoliation, stability, and uniformity with increasing temperature.
• Raman microscopy and TEM confirmed successful graphene exfoliation with minimal defects.

Conclusions:

• Optimized temperature (40°C) and input power (50%) are critical for efficient sonication-assisted LPE of graphite in water.
• Temperature control enhances graphene exfoliation, dispersion stability, and uniformity.
• This study provides a pathway for the large-scale production of high-quality graphene.