Nanomechanical behavior of penta-graphene nanotubes studied by reactive classical molecular dynamics simulation

Penta-graphene, a novel carbon allotrope composed exclusively of densely packed pentagonal rings, exhibits a negative Poisson’s ratio (auxetic behavior) and a wide bandgap of 3.2 eV, making it a promising candidate for advanced nanomaterial applications. In this theoretical study, we systematically investigate the nanostructural stability, dynamic behavior, and nanomechanical properties of single-walled penta-graphene nanotubes (PGNTs) formed by rolling up monolayer penta-graphene. Using reactive (ReaxFF) classical molecular dynamics simulations, we examine three distinct PGNT configurations: β-(n, n), @(n, n), and zigzag (n, 0). Our simulations reveal that the Young’s modulus of PGNTs ranges from 458.17 to 680.26 GPa, the ultimate tensile strength (UTS) varies between 54.45 and 87.10 GPa, and the critical strain spans 15.14–23.63%. Analysis of the fracture behavior indicates a consistent pattern across all configurations, with fracture initiation predominantly occurring at carbon–carbon bonds aligned with the tensile (z) direction. These findings provide new insights into the mechanical resilience and failure mechanisms of PGNTs, offering valuable guidance for the design of next-generation nanoelectromechanical systems and advanced composite materials.