  During the fabrication process of large scale silicene through common
chemical vapor deposition (CVD) technique, polycrystalline films are quite
likely to be produced, and the existence of Kapitza thermal resistance along
grain boundaries could result in substantial changes of their thermal
properties. In the present study, the thermal transport along polycrystalline
silicene was evaluated by performing a multiscale method. Non-equilibrium
molecular dynamics simulations (NEMD) was carried out to assess the interfacial
thermal resistance of various constructed grain boundaries in silicene as well
as to examine the effects of tensile strain and the mean temperature on the
interfacial thermal resistance. In the following stage, the effective thermal
conductivity of polycrystalline silicene was investigated considering the
effects of grain size and tensile strain. Our results indicate that the average
values of Kapitza conductance at grain boundaries at room temperature were
estimated nearly 2.56*10^9 W/m2K and 2.46*10^9 W/m2K through utilizing Tersoff
and Stillinger-Weber interatomic potentials, respectively. Also, in spite of
the mean temperature whose increment does not change Kapitza resistance, the
interfacial thermal resistance can be controlled by applying strain.
Furthermore, it was found that, by tuning the grain size of polycrystalline
silicene, its thermal conductivity can be modulated up to one order of
magnitude.
