Structural and Thermal Stability of Graphyne and Graphdiyne Nanoscroll Structures

Area of Science:

• Materials Science
• Nanotechnology
• Computational Chemistry

Background:

• Graphynes and graphdiynes are 2D carbon allotropes featuring hexagonal rings linked by acetylenic groups, possessing both sp and sp² hybridized carbon atoms.
• These materials, analogous to graphene, can form nanoscroll structures resembling rolled papyrus.
• Graphynes have one acetylenic group, while graphdiynes have two, distinguishing them from each other and graphene.

Purpose of the Study:

• To investigate the structural and thermal stability of various graphyne and graphdiyne nanoscrolls.
• To compare the stability of these nanoscrolls with that of graphene nanoscrolls.
• To elucidate the factors influencing the stability of graphyne and graphdiyne nanoscrolls.

Main Methods:

• Molecular dynamics simulations were employed to study the nanoscrolls.
• Reactive potentials were utilized to accurately model atomic interactions.
• Simulations were conducted at temperatures up to 1000 K to assess thermal stability.

Main Results:

• All studied graphyne (α, β, γ) and graphdiyne (α, β, γ) nanoscroll structures were found to be stable.
• These nanoscrolls demonstrated lower stability compared to analogous graphene nanoscrolls.
• Increased structural porosity in graphynes and graphdiynes leads to decreased π-π stacking interactions, explaining their reduced stability.

Conclusions:

• Graphyne and graphdiyne nanoscrolls are viable nanostructures with demonstrated stability.
• Their inherent porosity and weaker π-π stacking interactions make them less stable than graphene nanoscrolls.
• These findings provide insights into the mechanical and thermal properties of novel 2D carbon allotropes for potential applications.