Strain/stress engineering on the mechanical and electronic properties of phosphorene nanosheets and nanotubes

摘要

Phosphorene is demonstrated to have a great potential in the electronics applications. In this work, the first-principle calculations are employed to predict the mechanical properties and the electronic structure of phosphorene nanosheets and nanotubes. Compared with that of nanosheets, the maximum tensile stress of nanotubes decreases from 17.66 GPa to 11.73 GPa in the zigzag direction and 7.56 GPa to 5.95 GPa in the armchair direction. The ultimate tensile strain of nanosheets is about 27% in the armchair and 25% in the zigzag directions. However, the maximum strain of the zigzag nanotubes decreases to 24% and the ultimate strain of the armchair nanotube is about 14.4%. It presents that the tensile modulus will decrease with the increasing tension, while the compression modulus increases with increasing compression. The results show that zigzag-direction stress will affect the covalent bonds largely, while the armchair-direction stress influences the lone-pair electrons more. Within the allowable strain, the band structure and effective mass of carriers are calculated. The CBM and VBM change their positions when the stress is applied. The effective mass of nanosheets and nanotubes is strongly affected by strain.