Abstract:We design some graphene superlattice structures with ultra-low thermal conductivity 121 W/mK, which is only 6% of the straight graphene nanoribbons. The thermal conductivity of graphene superlattice nanoribbons (GSNRs) is investigated by using molecular dynamics simulations. It is reported that the thermal conductivity of graphene superlattice nanoribbons is significantly lower than that of the straight graphene nanoribbons (GNRs). Compared with the phonon spectra of straight GNRs, GSNRs have more forbidden bands. The overlap of phonon spectra between two supercells is shrinking.