[17a-Z29-1~10] 22.1 Joint Session M "Phonon Engineering"

▼ [17a-Z29-8] Tuning Thermal Conductance Across Two-dimensional Layered van der Waals Materials via Interfacial Mismatch and Coupling Engineering

〇(PC)Wenyu Yuan¹, Kan Ueji¹, Takashi Yagi², Takahiko Endo¹, Hong En Lim¹, Yasumitsu Miyata¹, Yohei Yomogida¹, Kazuhiro Yanagi¹ (1.Tokyo Metropolitan Univ., 2.AIST)

Keywords: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.