Graphene/hexagonal boron nitride (h-BN) van der Waals (vdW) heterostructure has aroused great interest because of the unique Moiré pattern. In this study, we use molecular dynamics simulation to investigate the influence of the interlayer rotation angle θ on the interfacial thermal transport across graphene/h-BN heterostructure. The interfacial thermal conductance G of graphene/h-BN interface reaches 509 MW/(m2K) at 500 K without rotation, and it decreases monotonically with the increase of the rotation angle, exhibiting around 50% reduction of G with θ = 26.33°. The phonon transmission function reveals that G is dominantly contributed by the low-frequency phonons below 10 THz. Upon rotation, the surface fluctuation in the interfacial graphene layer is enhanced, and the transmission function for the low-frequency phonon is reduced with increasing θ, leading to the rotation angle-dependent G. This work uncovers the physical mechanisms for controlling interfacial thermal transport across vdW heterostructure via interlayer rotation.

κCNPnC showed a non-monotonic dependence on porosity, and the localization of coherent phonons induced a substantial suppression of κD-C3N.

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Thermal rectification is a nonreciprocal thermal transport phenomenon, which typically takes place in asymmetric structures or hetero-junctions. In this work, we propose a new route to achieve remarkable thermal rectification even in pristine single-layer graphene without asymmetry by engineering the thermal contacts at the two ends. When setting a fixed long thermal contact at one end and varying the length of thermal contact at the other end, our molecular dynamics simulations demonstrate that notable thermal rectification efficiency can be achieved with very short thermal contact, which vanishes in the limit of long thermal contact. Such a strategy of asymmetric thermal contact can provide a significant enhancement of thermal rectification efficiency, achieving around 920% thermal rectification in the short sample with a length of 200 nm and around 110% thermal rectification in the micrometer scale sample. Phonon participation ratio analysis reveals that the strong localization of low-frequency acoustic phonons is induced by the short thermal contact in the backward direction, leading to a significant temperature jump at the short thermal contact in the backward direction and thus the thermal rectification in pristine single-layer graphene. Our study provides a new path to achieve notable thermal rectification even in the symmetric structures by engineering the thermal contact.