Mechanical properties and fracture dynamics of TH graphyne nanotubes: A molecular dynamics study on structural and environmental influences

This study investigates the mechanical properties of TH graphyne nanotubes through molecular dynamics simulations, employing a modified AIREBO potential to accurately model atomic interactions. The research systematically examines the influence of structural parameters — side length, diameter and number of walls — as well as external factors such as temperature and defect density on the tensile behavior of the nanotubes. Results indicate that the armchair configuration consistently outperforms the zigzag orientation in terms of elastic modulus, ultimate stress and toughness, attributed to its symmetric bond structure that enhances load distribution and resilience. Increases in side length and temperature reduce mechanical strength, while higher defect percentages further compromise performance by introducing stress concentration points. Multi-walled structures exhibit enhanced properties due to interlayer interactions, with the armchair variant showing greater gains. Fracture analyses reveal distinct failure mechanisms, with armchair nanotubes displaying gradual breakdown and zigzag nanotubes undergoing rapid, localized rupture. These findings provide critical insights into the design and optimization of TH graphyne nanotubes for advanced nanomaterial applications, emphasizing the interplay between structural geometry, environmental conditions and mechanical performance.