The creation of racks and nanopores creation in various allotropes of boron due to the mechanical loads

Abstract

Two-dimensional (2D) materials have recently attracted a great attraction. This paper provides a detailed discussion on the rupture mechanisms of different allotropes of boron. As a new 2D material by using a reactive molecular dynamics model, probable types of rupture for borophene sheets were studied, among which two dominant mechanisms were observed: creation of the cracks and formation of nanopores. The results obtained are compared to those for graphene and h-BN nano sheets, although the rupture mechanism was completely different from the graphene and h-BN sheets. The simulations suggested that borophene might remain more stable against external mechanical loads than graphene and BN sheets. Cracking leads to larger strain along the loading direction, whereas the creation of local pores spends the imposed energy for breaking the internal bonds and so flowing the external energy into the various bonds increases the number of pores. For the armchair-types, cracking is a dominant mechanism while for the zigzag-type the common mechanism is the creation of nanopores. These interesting results may help to design a new class of semiconductors that remain stable even when are sustaining uncontrollable external stresses.