Thermal Conductivity of the Partly Covered Inner Tube in a Double-Walled Carbon Nanotube with Varied Coverage Ratios

We present a study of the thermal conductivity of a partly covered inner tube in a double-walled carbon nanotube with varied covering ratios using a non-equilibrium molecular dynamics method. Our results show that the thermal conductivity of the inner tube changes non-linearly and non-monotonically with the increasing coverage ratio, forming a V-shaped curve. Minimal conductivity occurs at the coverage ratio of 58%, with its value being 69% of the maximal conductivity, which appears in the full coverage case. We analyze three mutually competitive mechanisms that result in this thermal conductivity behavior with the assistance of a phonon spectrum calculation.