This study presents the experimental realization of metallic NbS2-based one-dimensional van der Waals heterostructures applying a modified NaCl-assisted chemical vapor deposition approach. By employing a "remote salt" strategy, precise control over NaCl supply was achieved, enabling the growth of high-quality coaxial NbS2 nanotubes on single-walled carbon nanotube-boron nitride nanotube (SWCNT-BNNT) templates. With the remote salt strategy, the morphologies of as synthesized NbS2 could be controlled from 1D nanotubes to suspended 2D flakes. Structural characterization via high-resolution transmission electron microscopy (HRTEM) and scanning transmission electron microscopy (STEM) confirms the formation of crystalline NbS2 nanotubes, revealing a distinct bi-layer preference compared to monolayer-dominated semiconducting transition metal dichalcogenide analogs. Optical analyses using UV-vis-NIR and FTIR spectroscopy highlight the metallic nature of NbS2. With Raman analysis, oxidation studies demonstrate relative higher degradation rate of 1D NbS2 under ambient conditions. Density functional theory (DFT) calculations further elucidate the stabilization mechanism of bi-layer NbS2 nanotubes, emphasizing interlayer charge transfer and Coulomb interactions. This work establishes a robust framework for synthesizing metallic 1D vdW heterostructures, advancing their potential applications in optoelectronics and nanodevices.
@article{arxiv.2507.03274,
title = {Metallic NbS2 one-dimensional van der Waals heterostructures},
author = {Wanyu Dai and Yongjia Zheng and Akihito Kumamoto and Yanlin Gao and Sijie Fu and Sihan Zhao and Ryo Kitaura and Esko I. Kauppinen and Keigo Otsuka and Slava V. Rotkin and Yuichi Ikuhara and Mina Maruyama and Susumu Okada and Rong Xiang and Shigeo Maruyama},
journal= {arXiv preprint arXiv:2507.03274},
year = {2025}
}