Effects of temperature and strain rate on mechanical behaviors of Stone-Wales defective monolayer black phosphorene

TL;DR

This study uses molecular dynamics simulations to analyze how temperature, strain rate, and Stone-Wales defects influence the mechanical behavior and phase transitions of monolayer black phosphorene, providing insights for material design.

Contribution

It reveals the effects of temperature, strain rate, and defects on black phosphorene's mechanics and observes phase transitions and defect healing, advancing understanding of phosphorene's properties.

Findings

Mechanical strength decreases with temperature and lower strain rate.

Phase transition to nd nd phases occurs at high temperature and low strain rate.

Self-healing of defects observed under certain tension conditions.

Abstract

The mechanical behaviors of monolayer black phosphorene (MBP) are explored by molecular dynamics (MD) simulations using reactive force field. It is revealed that the temperature and strain rate have significant influence on mechanical behaviors of MBP, and they are further weakened by SW (Stone-Wales) defects. In general, the tensile strength for both of the pristine and SW defective MBP decreases with the increase of temperature or decreasing of strain rate. Surprisingly, for relatively high temperature and low strain rate, phase transition from the black phosphorene to a mixture of {\beta}-phase ({\beta}-P) and {\gamma}-phase ({\gamma}-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.