Strongly Anisotropic Thermal Conductivity of Free‐Standing Reduced Graphene Oxide Films Annealed at High Temperature

Thermal conductivity of free‐standing reduced graphene oxide films subjected to a high‐temperature treatment of up to 1000 °C is investigated. It is found that the high‐temperature annealing dramatically increases the in‐plane thermal conductivity, K , of the films from ≈3 to ≈61 W m −1 K −1 at room temperature. The cross‐plane thermal conductivity, K ⊥ , reveals an interesting opposite trend of decreasing to a very small value of ≈0.09 W m −1 K −1 in the reduced graphene oxide films annealed at 1000 °C. The obtained films demonstrate an exceptionally strong anisotropy of the thermal conductivity, K/K ⊥ ≈ 675, which is substantially larger even than in the high‐quality graphite. The electrical resistivity of…

• MA
  Microelectronics Advanced Research Corporation
• DA
  Defense Advanced Research Projects Agency