Full Program »

Effects of vacancies and inclusions in the mechanical properties of silicene

The potential of atomistically two-dimensional (2D) materials has created a new paradigm of materials science. Among the various 2D crystalline structures is silicene – a monolayer allotrope of silicon - similar to the structure of graphene. While this material has been previous investigated for potential in electrical applications, successful implementation in such nanodevices requires full understanding of its mechanical behavior. Here, the mechanical properties of silicene containing different percentages of vacancies or inclusions under tensile loading were investigated. Full atomistic first-principles-based ReaxFF molecular dynamics (MD) were used. The influence of the size and distribution of the defects on the mechanical properties of silicene were studied. It was found that the results show anisotropic flaw tolerance in the 2D structure, where the modulus and the ultimate strength are sensitive to the orientation of the lattice. Furthermore, we derive general scaling laws for the effects of defect density on the structure, allowing extrapolation of mechanical performance to silicene structures with different levels of defect density.

Author(s):

Ruth E. Roman    
Northeastern University
United States

Steven W. Cranford    
Northeastern University
United States