Stabilization of NbTe₃, VTe₃, and TiTe₃ via Nanotube Encapsulation

Abstract

The structure of MX3 transition metal trichalcogenides (TMTs, with M a transition metal and X a chalcogen) is typified by one-dimensional (1D) chains weakly bound together via van der Waals interactions. This structural motif is common across a range of M and X atoms (e.g. NbSe3, HfTe3, TaS3), but not all M and X combinations are stable. We report here that three new members of the MX3 family which are not stable in bulk, specifically NbTe3, VTe3, and TiTe3, can be synthesized in the few-to single-chain limit via nano-confined growth within the 2 stabilizing cavity of multi-walled carbon nanotubes. Transmission electron microscopy (TEM) and atomic-resolution scanning transmission electron microscopy (STEM) reveal the chain-like nature and the detailed atomic structure. The synthesized materials exhibit behavior unique to few-chain quasi-1D structures, such as multi-chain spiraling and a trigonal anti-prismatic rocking distortion in the single-chain limit. Density functional theory (DFT) calculations provide insight into the crystal structure and stability of the materials, as well as their electronic structure.

Van der Waals heterostructures with one-dimensional atomic crystals

“…6g and h). There are also other reported cases about the phase change of fillings in NT, including torsional instability and trigonal antiprismatic rocking distortion of single MX 3 (e.g., NbSe 3 , NbTe 3 , VTe 3 , and TiTe 3 ) atomic chain in SWCNTs [66,152], transition of iodine dimers between trimers [26], Peierls structural distortion of single-atomic Te chains [25], helices in 1D cobalt iodide [153], solid-amorphous phase change of GeTe [154] and ordered ice nanotube [155], etc. Copyright 2019, American Chemical Society.…”

“…demonstrated that multiwalled CNT encapsulation is an effective method to prepare extremely narrow 1D transition metal trichalcogenides (TMTC) nanowires [66,152].…”

Precise Synthesis of Carbon Nanotubes and One‐Dimensional Hybrids from Templates†

“…Their further work showed that MX 3 displayed behavior unique to few‐chain quasi‐1D structures, such as few‐chain spiraling and a trigonal antiprismatic rocking distortion in the single‐chain limit. [ 234 ]…”

Preparation, thermal analysis, and crystal structure refinement of the quaternary alloy (CuIn)2NbTe5

“…It has been also reported that it is a superconductor metal with T c ∼ 0.7 K [28]. NbTe 3 is not stable in bulk, however, can be synthesized via nanoconfined growth within the stabilizing cavity of multiwalled carbon nanotubes [29]. NbTe 4 crystallizes in a tetragonal structure (s.g P 42c) [29] and is a charge-density-wave (CDW) material under ambient pressure.…”

“…NbTe 3 is not stable in bulk, however, can be synthesized via nanoconfined growth within the stabilizing cavity of multiwalled carbon nanotubes [29]. NbTe 4 crystallizes in a tetragonal structure (s.g P 42c) [29] and is a charge-density-wave (CDW) material under ambient pressure. However, with in- creasing pressure, the CDW transition temperature is gradually suppressed, and superconducting transition, which is fingerprinted by a steep resistivity drop, emerges at pressures above 12.4 GPa.…”