Investigation of the thermal‐transport properties for silicon nanofilm covered with graphene via nonequilibrium molecular dynamics

Abstract

AbstractNonequilibrium molecular dynamics (NEMD) is used to investigate the thermal‐transport properties of a silicon nanofilm covered with graphene (Gr/Si/Gr nanofilm). The investigation results demonstrate that graphene can enhance the thermal‐transport properties and weaken the ballistic characteristics of silicon nanofilm. Under the action of a small strain, the thermal conductivity decreases with the growth of tensile and compressive strain, respectively. In addition, the higher‐frequency phonons in graphene give more contributions to the variation of thermal conductivity of Gr/Si/Gr nanofilm under strain. The thermal conductivity of Gr/Si/Gr nanofilm increases linearly with the increase of temperature in the lower‐temperature regime due to the quantum effect, and begins to clearly decrease when the temperature exceeds a definite value.