Unprecedented New Crystalline Forms of SnSe in Narrow to Medium Diameter Carbon Nanotubes

Abstract

We report the observation of four unprecedented new crystalline forms of SnSe, obtained as a result of encapsulation in narrow to medium diameter single-walled carbon nanotubes. Aberration-corrected scanning transmission electron microscopy at 80 kV revealed linear, zigzag, helical (i.e., 2 × 1) atomic chains and a new form of encapsulated SnSe. This new form is apparently isostructural to free-standing MoS, MoSe, and WSe extreme nanowires etched from the corresponding monolayer dichalcogenides and also recently observed encapsulated MoTe. A structural model has been attained from annular dark-field (ADF) images. The experimental imaging agrees well with image simulations produced from models anticipated for the new structural forms.

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.…”

“…So far, quasi-1D batches of molybdenum chalcogenide wires have been widely obtained in bulk inorganic synthesis using various counterions (such as alkali metals or iodine) to stabilize these atomic wires. , Free bundles of Mo 6 S 6 wires without counterions, aligned and equally spaced arrays of Mo 6 S 6 wires on Cu(111) substrate, as well as heterostructures of 1D Mo 6 Te 6 and 2D MoTe 2 have also been reported . Recently, isolated Mo 6 Te 6 and Sn 6 Se 6 wires were fabricated inside single-wall carbon nanotubes. − Individual wires of MX (M = Mo, W; X = S, Se), MoS x Se 1– x , and Mo x W 1– x S alloys 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.…”

Efficient growth and characterization of one-dimensional transition metal tellurides inside carbon nanotubes

“…4c, S6), which are equivalent to the corresponding values of MoTeNWs and SnSeNWs. 34 The filling yield of WTeNWs is comparable to that of MoTeNWs. In HAADF-STEM images, heavier W atoms (Z = 74) look brighter than Mo atoms (Z = 42) due to the strong electron scattering (Fig.…”

Van der Waals heterostructures with one-dimensional atomic crystals

“…In 1D vdW heterostructure, the filled material is spatially confined in the centre of NT, and the sheath and protection from NT enables the realization of 1D nanostructures that are instable in air condition. In some cases, these 1D atomic chains would undergo a structure change and phase transition if the tubes have suitable small inner diameter [150,151]. For example, MoTe atomic chains was synthesized and isolated by CNTs encapsulation [98].…”