Many scholars have demonstrated XAV-939 order that these defects are obstacles to heat transfer and create additional sources of phonon scattering in graphene [12–16], especially when the characteristic dimension is less than the phonon mean free path (approximately 775 nm at room temperature) [2]. Hao et al. [13] performed molecular dynamics (MD) simulations on defected graphene sheets. They observed

that the increasing defect concentration dramatically reduces the thermal conductivity of graphene. Chien et al. [14] investigated the effect of impurity atoms in graphene and found a rapid drop in thermal conductivity, where hydrogen coverage down to as little as 2.5% of the carbon atoms reduces the thermal conductivity by about 40%. So we can conclude that the thermal transport properties of graphene are very sensitive to its own structures. Besides these defects, the structural configuration is another important but less studied factor impacting the thermal properties, and thus, it can affect the lifetime and reliability

of the graphene-based selleck chemicals nanodevices further because these devices have more complex shapes in engineering situations. Therefore, from a practical point of view, the investigation on how to predict or tune the thermal transport properties of graphene with a variety of shapes is especially useful for thermal management. Recently, Xu et al. [17] investigated the transport properties of various graphene junctions and quantum dots using nonequilibrium Green’s function method and found that the thermal conductance is insensitive to the detailed structure of the contact region but substantially limited by the narrowest part of the system. Huang et al. [18] constructed

a sandwich structure with atomistic Green’s function method, where two semi-infinite graphene sheets are bridged by a graphene nanoribbon (GNR). They mainly focused on the phonon transport behavior in GNR and observed that the thermal conductance increases with the width of GNR at fixed length and decreases with GNR length at fixed width. This paper presents the effect of the nanosized constrictions on the thermal transport properties of graphene studied by the nonequilibrium molecular dynamics (NEMD) simulations. 5 FU We calculate the thermal transport properties of graphene with those constrictions, and the effects of the heat current and the width of the constriction were explored in detail. Further, based on the phonon dynamics theory, we develop an analytical model for the ballistic resistance of the nanosized constrictions in two-dimensional nanosystems, which agrees well with the simulation results in this paper. selleck chemical Methods Here, we employed the NEMD method [19–24] to simulate the thermal transport in graphene. The simulated system with constrictions is illustrated in Figure 1, which is originally an 18.2-nm-long and 11.