(Invited) Growth and Characterization of Various Van Der Waals Hetero-Nanotubes Based on Single-Walled Carbon Nanotubes

Abstract

We have synthesized a new coaxial nanotube structure, in which mono- or few-layer hexagonal boron nitride nanotube (BNNT) seamlessly wrap around a single-walled carbon nanotube (SWCNT); SWCNT@BNNT [1]. We named these as one-dimensional van der Waals hetero-nanotubes, because we found no correlation between chiral angle of inner SWCNT and outer BNNT for ‘double-walled’ SWCNT@BNNT. We have further developed the 1D coating CVD of transition metal dichalcogenide nanotubes (TMD-NT), such as MoS2 nanotubes and WSe2 nanotubes. We can grow MoS2 nanotubes around relatively large diameter SWCNT or SWCNT@BNNT. These nanotubes can be labelled as SWCNT@TMD-NT or SWCNT@BNNT@TMD-NT as shown in Fig. 1. Because BNNT is thermally more stable than SWCNT, we can remove SWCNT from SWCNT@BNNT by the gentle oxidation process. Hence, we can produce BNNT with inner diameter determined by the original SWCNT. Then, the MoS2 CVD can result BNNT@TMD-NT or TMD-NT@BNNT as shown in Fig. 1. Recently, CVD growth of carbon nanotubes over SWCNT@BNNT is realized, resulting SWCNT@BNNT@SWCNT. These hetero-nanotubes are characterized by HR-TEM, STEM-EELS, optical absorption, FT-IR, Raman scattering, Photoluminescence spectroscopy.Part of this work was supported by JSPS KAKENHI Grant Numbers JP15H05760, JP18H05329.Reference:[1] R. Xiang, T. Inoue, Y. Zheng, A. Kumamoto, Y. Qian, Y. Sato, M. Liu, D. Gokhale, J. Guo, K. Hisama, S. Yotsumoto, T. Ogamoto, H. Arai, Y. Kobayashi, H. Zhang, B. Hou, A. Anisimov, Y. Miyata, S. Okada, S. Chiashi, Y. Li, E. I. Kauppinen, Y. Ikuhara, K. Suenaga, S. Maruyama, arXiv:1807.06154 (2019). Figure 1