On the diversity in the thermal transport properties of graphene: A first-principles-benchmark study testing different exchange-correlation functionals

Due to the extraordinary mechanical, electronic, optical, and thermal transport properties, graphene had been one of the most fascinating and extensively studied two-dimensional materials in recent years. Benefiting from the extremely high thermal conductivity, the thermal transport in graphene has received exceptional attention in both experimental and theoretical studies. In this paper, based on first-principles calculations, we performed systematic study on the thermal transport properties of graphene using 10 different exchange-correlation (XC) functionals combined with ultrasoft or projector augmented wave (PAW) pseudopotentials. The thermal transport properties of graphene show distinct diversity for different XC functionals despite their overall good agreement with experimental measurements. It is found that the thermal conductivity of graphene could range from 1936 to 4376 Wm(-1) K-1 with different XC functionals employed. The reason for the diversity in the thermal transport properties of graphene is analyzed based on the insight into the mode level phonon behaviors. Our study executed a comprehensive investigation of the thermal transport properties of graphene with different XC functionals employed, which would shed light on future researches related to graphene and other novel materials.