Isolation of Single-Wired Transition-Metal Monochalcogenides by Carbon Nanotubes

Abstract

The successful isolation of single layers from two-dimensional (2D) van der Waals (vdW)-layered materials has opened new frontiers in condensed matter physics and materials science. Their discovery and unique properties laid the foundation for exploring 1D counterparts. However, the isolation of 1D vdW-wired materials has thus far remained a challenge, and effective techniques are demanded. Here we report the facile synthesis of isolated transition-metal monochalcogenide MoTe nanowires by using carbon nanotubes (CNTs) as molds. Individual nanowires are perfectly separated by CNTs with a minimal interaction, enabling detailed characterization of the single wires. Transmission electron microscopy revealed unusual torsional motion of MoTe nanowires inside CNTs. Confinement of 1D vdW-wired materials to the nanotest tubes might open up possibilities for exploring unprecedented properties of the nanowires and their potential applications such as electromechanical switching devices.

Atomic Wires of Transition Metal Chalcogenides: A Family of 1D Materials for Flexible Electronics and Spintronics

“… 16 Recently, isolated Mo 6 Te 6 and Sn 6 Se 6 wires were fabricated inside single-wall carbon nanotubes. 17 − 20 Individual wires of MX (M = Mo, W; X = S, Se), MoS x Se 1– x , and Mo x W 1– x S alloys 14 were also synthesized by sculpting their monolayer counterparts. These atomic wires exhibit self-adaptive connections to the monolayers and remain conductive under severe mechanical deformation.…”

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

“…reported that the single layers are isolated from 2D vdW‐layered material MoTe, which was achieved by the formation of discontinuous torsional motion in MoTe@ SWCNTs (Figure 19b). [ 42 ] They further extended to synthesize 1D MoTe and WTe nanowires by vacuum annealing of suitable metal (Mo, W) oxides with Te. These inner 1D vdW nanowires interact strongly with the outer SWCNT sheaths, inducing p‐type doping of SWCNTs.…”

“…There is an ever‐growing list of materials such as C 60 , nanodiamonds, linear carbon chains, transition metal chalcogenides being isolated into CNTs [ 37‐39 ] and existing a number of new low‐dimensional crystals such as hexagonal boron nitride (BN), molybdenum disulfide, transition metal chalcogenides coaxially stacked outside CNTs. [ 40‐42 ] These properties of CNT hybrids, which could be tailored, enable hybrid materials readily applicable as functional materials and create various possible applications. The inner structure and property of CNT with enriched electron cloud are also unique and can be modulated by filling channels.…”

“…[ 66 ] Recent achievements have demonstrated that the limited space and unique electronic properties of SWCNT cavity with diameter around 1 nm enable templating new phase 1D nanomaterials that may not be easy to obtain by other synthetic methods, such as linear carbon chains [ 67 ] and nanodiamonds, [ 39 ] and 1D counterparts rolling from 2D materials. [ 38,40,42,68 ] These rapid developments have revealed new findings to digest and new questions to contemplate. Therefore, it's perfect time to review progress in the field and identify new directions for future studies.…”

Electrically Driven Dynamics of Few‐Chain NbSe3

“…Low‐dimensional materials, when approaching the single‐plane or single‐chain limit, may display structures and properties very different from those of their bulk counterparts . Recently, it was shown that small numbers of chains of 1D van der Waals (vdW)–bonded materials, for example, NbSe 3 , can be encapsulated within the hollow core of carbon or boron nitride nanotubes .…”