Reversible conversion between graphene nanosheets and graphene nanoscrolls at room temperature

Area of Science:

• Materials Science
• Nanotechnology
• Chemistry

Background:

• Graphene, a 2D material, has unique properties but its conversion into 1D structures like nanoscrolls is challenging.
• Controlling the morphology and structure of graphene-based nanomaterials is crucial for advanced applications.

Purpose of the Study:

• To report a novel, facile, and reversible method for converting graphene nanosheets into graphene nanoscrolls and vice versa.
• To investigate the mechanism behind the rolling and unfolding of graphene structures.
• To explore potential applications in graphene nanoscroll fabrication and storage.

Main Methods:

• Graphene nanosheets were rolled into nanoscrolls using silver nitrate in ethanol.
• Nanoscrolls were subsequently unfolded back to nanosheets by adding ammonium hydroxide in ethanol.
• Morphological analysis was performed using optical microscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), and transmission electron microscopy (TEM).
• Structural integrity was confirmed using Raman spectroscopy.

Main Results:

• A reversible conversion between graphene nanosheets and nanoscrolls was achieved at room temperature.
• The process involves the formation and removal of silver cyanide particles on graphene edges, driving the rolling and unfolding.
• Characterization confirmed that the graphene structure and morphology remained intact throughout the reversible conversion process.

Conclusions:

• The study presents a new and straightforward approach for synthesizing graphene nanoscrolls and for graphene storage.
• The findings offer insights into the dynamic conversion between 2D and 1D carbon nanomaterials.
• This reversible transformation could pave the way for novel applications utilizing graphene's dimensional versatility.