Interacting Phonons between Layers in Raman Spectra of Carbon Nanotubes inside Boron Nitride Nanotubes

Desman Perdamaian Gulo; Nguyen Tuan Hung; Wei-Liang Chen; Shuhui Wang; Ming Liu; Esko I Kauppinen; Shigeo Maruyama; Yu-Ming Chang; Riichiro Saito; Hsiang-Lin Liu

doi:10.1021/acs.jpclett.3c02528

Interacting Phonons between Layers in Raman Spectra of Carbon Nanotubes inside Boron Nitride Nanotubes

J Phys Chem Lett. 2023 Nov 16;14(45):10263-10270. doi: 10.1021/acs.jpclett.3c02528. Epub 2023 Nov 8.

Authors

Desman Perdamaian Gulo¹, Nguyen Tuan Hung^{2

3}, Wei-Liang Chen⁴, Shuhui Wang⁵, Ming Liu⁵, Esko I Kauppinen⁶, Shigeo Maruyama⁵, Yu-Ming Chang⁴, Riichiro Saito^{1

2}, Hsiang-Lin Liu¹

Affiliations

¹ Department of Physics, National Taiwan Normal University, Taipei 11677, Taiwan.
² Department of Physics, Tohoku University, Sendai 980-8578, Japan.
³ Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai 980-8578, Japan.
⁴ Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan.
⁵ Department of Mechanical Engineering, School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan.
⁶ Department of Applied Physics, Aalto University School of Science, Espoo 15100, FI-00076 Aalto, Finland.

PMID: 37939010
DOI: 10.1021/acs.jpclett.3c02528

Abstract

We present the resonant Raman spectra of a single-wall carbon nanotube inside a multiwall boron nitride nanotube (SWNT@BNNT). At E_L = 1.58 eV, SWNT@BNNT exhibited resonant Raman spectra at 807 (ω_BN) and 804 cm^-1 (ω_Gr). Their intensities almost disappeared at E_L = 2.33 eV. We assigned ω_BN to the out-of-plane BN phonon mode that coupled with ω_Gr. At E_L = 4.66 eV, the G⁺ and G^- bands of the SWNT@BNNT red-shifted 3.8 cm^-1 compared with the SWNT, suggesting the interwall interactions between the in-plane modes of SWNT and BNNT. Moreover, the E_2g mode of the BNNT in SWNT@BNNT appeared at 1370.3 ± 0.1 cm^-1, which is undistinguishable for E_L < 3 eV because of the overlap with the D band frequency. The assignment of the present Raman spectra was confirmed through the first-principles calculations.