Melting and pre-melting of two-dimensional crystalline SiC nanoribbons

Abstract

A bstract Melting of two-dimensional hexagonal SiC nanoribbons (2D h -SiC) is studied by molecular dynamics (MD) simulations. Initial h -SiC nanoribbons are heated up from 50 K to 6000 K in order to study melting. Evolution of structure and thermodynamics of the models upon heating is analyzed. Melting of models with the armchair and zigzag edges is studied in order to clarify the edge type effects on melting. We find that in the initiated stage of melting, liquid-like atoms occur first in the edge region at temperature far below the melting point of nanoribbons and further heating leads to the homogeneous occurrence/growth of liquid-like atoms throughout the models. We find no role of the Stone-Wales defects in melting of 2D crystalline SiC nanoribbons unlike that found for melting of graphene. • Melting of 2D crystalline SiC nanoribbons: liquid-like atoms occur/grow only at the edge first, further heating leads to the homogeneous occurrence/growth of liquid-like atoms throughout the models. • We find that 10-fold rings are precursors for the formation of larger rings toward formation of the ring-like 2D SiC liquid. • No role of Stone-Wales defects in melting of SiC nanoribbons is found unlike that found for graphene