Introducing Structures from Hexagonal Borophene to Nitrophene and Their Thermal Conductivity Investigation Using a Reactive Molecular Dynamics Simulation.

In the present work, the thermal conductivity (TC) of hexagonal structures of boron nitride and borophene was investigated by a reactive molecular dynamics (MD) simulation. Also, to figure out the effect of the boron and nitrogen in the hexagonal structure, five other hypothetical structures were created (in addition to the structure of boron nitride and borophene) and their structures were represented by the symbol B x N y , where x refers to the number of boron atoms and y refers to the number of nitrogen atoms. In this regard, B 6 N 0 refers to borophene, B 3 N 3 is boron nitride, and B 0 N 6 is called nitrophene. The TC of B 6 N 0 and B 3 N 3 structures was calculated and compared with the literature values. Besides these two compounds, the five other structures have not been experimentally synthesized yet, so the TC of the five other hypothetical structures were predicted in the present work. The lowest TC belonged to B 3 N 3 , and the highest one was for B 0 N 6 . Based on the inherent potential of reactive MD simulation, during TC calculation, atoms' coordination and partial charges are changed and new bonds, rings, or even defects were automatically created on the surfaces. The coordination contour map showed that in B 3 N 3 , the atoms have collective movements like a large and single wave, while B 0 N 6 and B 6 N 0 have small group movements as vibrations. So, it became clear that the higher stability of structures caused more curved movements. In addition, the contour map of partial charges is calculated, and the results showed that the high differences in partial charge between atoms in the structure cause high TC, while small charge differences in the structure inhibit heat transfer and cause lower TC.