11:30 〜 11:45
▼ [17a-Z29-8] Tuning Thermal Conductance Across Two-dimensional Layered van der Waals Materials via Interfacial Mismatch and Coupling Engineering
キーワード:thermal conductance, heterostructures, van der Waals
The understanding of heat flow across solid interfaces and its control are extremely important for the applications of advanced electronics, thermal energy conversion, and thermal management in devices. Two-dimensional (2D) material family with ultrathin thickness as a new rising star makes it possible to tune the thermal property at the atomic-scale.[Y. Liu, Y. Huang, X. Duan. Nature, 567(7748), 323(2019)] For instance, the stacking structure of graphene, MoS2, and WSe2 shows extremely high thermal isolator property on a sub-2-nm scale [S. Vaziri, E. Yalon, M. M. Rojo, et al. Sci. Adv., 5(8), eaax1325 (2019)], and disordered WSe2 exhibited very low thermal conductivity [C. Chiritescu, D. G. Cahill, N. Nguyen, et al., Science, 315(5810), 351 (2007)]. Therefore, experimental understanding on the heat flow across the 2D interfaces is of great importance. Here, we provide a PEG-assistant TDTR method to evaluate thermal conductance (TC) of atomic-scale-thin materials with improved sensitivity. The TC of a series of 2D vdW materials has been investigated, in which MoSe2-MoS2-MoSe2-MoS2 heterostructure demonstrates the lowest TC, which is one order of magnitude lower than air at room temperature. The interfacial mismatch and interfacial coupling effect are two main factors to tune TC for 2D-layered vdW materials.