Growth and Properties of Dislocated Two-dimensional Layered Materials

Abstract

Two-dimensional (2D) layered materials hosting dislocations have attracted considerable research attention in recent years. In particular, screw dislocations can result in a spiral topology and an interlayer twist in the layered materials, significantly impacting the stacking order and symmetry of the layers. Moreover, the dislocations with large strain and heavily distorted atomic registry can result in a local modification of the structures around the dislocation. The dislocations thus provide a useful route to engineering optical, electrical, thermal, mechanical and catalytic properties of the 2D layered materials, which show great potential to bring new functionalities. This article presents a comprehensive review of the experimental and theoretical progress on the growth and properties of the dislocated 2D layered materials. It also offers an outlook on the future works in this promising research field.

Epitaxial Integration and Defect Structure of Layered SnSe Films on PbSe/III–V Substrates

“…Layered vdW materials frequently grow via spiral growth and step-flow mechanisms, − implying a significant bias for adhesion at step edges and high adatom mobility on the top of a vdW sheet. A notable example of spiral growth in a vdW-bonded material comes from Liu at al., who grew Bi 2 Se 3 on chemically incompatible graphene/SiC via 2D nucleation.…”

Enantioselective Seleno‐Michael Addition Reactions Catalyzed by a Chiral Bifunctional N‐Heterocyclic Carbene with Noncovalent Activation

“…Proton sources were found to be essential for highly asymmetric induction and suppression of retro‐Michael reactions. For example, use of hexafluoro isopropanol (HFIP) is essential for C‐, N‐, and S‐Michael reactions [22a–c] and 1,1′‐bi‐2‐naphthol (BINOL) was identified as a crucial hydrogen‐bonding cocatalyst in the P‐Michael addition [22g] . During our investigation of the asymmetric aza‐Michael reaction involving oxycarbamates, we discovered that Waser's chiral triazolium‐thiourea catalyst delivered a remarkable synergistic effect in controlling the nitrogen‐containing β‐chirality [22f] .…”

Spiral WSe2 with Interlayer Twist for Memristive and Neuromorphic Device Applications

“…The ab initio band structure calculations clearly show that high-symmetry stacking of the TMDC layers results in weak interlayer couplings and changes in electronic structure . However, twisted and stacked TMDC layers have been found to exhibit new quantum observations such as superconductivity with vanishing electrical resistance, tunable Mott insulators, and moiré excitons . Twisted spiral structures of TMDCs are induced by screw-dislocation-driven growth .…”

“…15 However, twisted and stacked TMDC layers have been found to exhibit new quantum observations such as superconductivity with vanishing electrical resistance, tunable Mott insulators, and moiréexcitons. 16 Twisted spiral structures of TMDCs are induced by screw-dislocation-driven growth. 17 During chemical vapor deposition (CVD) growth, the incorporation of threading dislocation acts as a driving force to break the symmetry.…”