講演情報
[22p-C501-3]Tuning cross-plane thermal conductivity of graphite by MnCl2-FeCl3 co-intercalation
〇(D)Harsh Chandra1, Shun Sasano1, Sumire Miyakoshi2, Xu Bin1, Ryo Ishikawa1, Noda Suguru2, Naoya Shibata1, Junichiro Shiomi1 (1.The Univ. of Tokyo, 2.Waseda University)
キーワード：
thermal conductivity、graphite intercalation、time domain thermoreflectance
Understanding thermal transport in layered materials enables tuning of thermal conductivity by intercalating with large guest atoms in its nanospaced interlayers. We report significant tunability in crossplane lattice thermal conductivity (κz) of graphite through co-intercalation with MnCl2 and FeCl3, forming graphite co-intercalation compound (co-GIC). Controllability is consistent from 78 K to 298 K. Furthermore, this tunability is also observed across the entire thickness range (30 nm to 1.5 µm). Scanning transmission electron microscopy reveals a stage-3 superlattice-like layered nanostructure which is supported by Raman spectroscopy mapping. Phonon scattering mechanisms are analyzed using a Debye-Callaway model, showing a 5-fold increase in boundary scattering rate at room temperature due to a 2-orders suppression in phonon transport length scale. This explains the 2-orders jump in contribution from boundary scattering to κz at 298 K, confirming the large tunability of c-axis κz.