Effects of Temperature and Strain Rate on Mechanical Behaviors of Stone-Wales Defective Monolayer Black Phosphorene

The mechanical behaviors of monolayer black phosphorene (MBP) are explored by molecular dynamics (MD) simulations using a reactive force field. It is revealed that the temperature and strain rate have a significant influence on the mechanical behavior of MBP, and they are further weakened by SW (Stone-Wales) defects. In general, the tensile strength for both the pristine and SW defective MBP decreases with the increase of temperature or decrease of strain rate. Surprisingly, for relatively high temperature (>300 K) and low strain rate (<5.0 × 10^-8 fs^-1), a phase transition from the black phosphorene to a mixture of β-phase (β-P) and γ-phase (γ-P) is observed for the SW-2 defective MBP under armchair tension, while self-healing of the SW-2 defect is observed under zigzag tension. A deformation map of SW-2 defective MBP under armchair tension at different temperature and strain rate is established, which is useful for the design of phosphorene allotropes by strain. The results presented herein yield useful insights for designing and tuning the structure, and the mechanical and physical properties of phosphorene.