Lattice thermal conductivity of pure and doped (B, N) Graphene

Abstract

In this paper, the effect of B and N doping on the phonon induced thermal conductivity of graphene has been investigated. This study is important when one has to evaluate the usefulness of electronic properties of B and N doped graphene. We have performed the calculations by employing density functional perturbation theory(DFPT) to calculate the inter-atomic forces / force constants of pristine/doped graphene. Thermal conductivity calculations have been carried out by making use of linearized Boltzmann transport equations (LBTE) under single-mode relaxation time approximation(RTA). The thermal conductivity of pristine graphene has been found to be of the order of 4000 W/mK at 100 K, which decreases gradually with an increase in temperature. The thermal conductivity decreases drastically by 96% to 190 W/mK when doped with 12.5% B and reduces by 99% to 30 W/mK with 25% B doping. When graphene is doped with N, the thermal conductivity decreases to 4 W/mK and 55 W/mK for 12.5% and 25% doping concentration, respectively. We have found that the thermal conductivity of doped graphene show less sensitivity to change in temperature. It has also been shown that the thermal conductivity of graphene can be tuned with doping and has a strong dependence on doping concentration.

Keywords

• thermal conductivity
• graphene
• density functional theory