Stability, Structure and Reconstruction of 1H‐Edges in MoS₂

Abstract

Density functional studies of the edges of singlelayer 1H-MoS 2 are presented.T his phase presents ar ichv ariability of edges that can influencet he morphology and properties of MoS 2 nano-objects, play an important role in industrial chemical processes, and find future applications in energy storage, electronics and spintronics. The so-called Mo-100 %S edges vertical S-dimersw ere confirmedt ob e stable, however the authors also identified af amilyo fm etastable edges combining Mo atoms linked by two-electron donor symmetrical disulfide ligandsa nd four-electron donor unsymmetrical disulfide ligands. These may be entropically favored, potentially stabilizing them at high temperatures as a" liquid edge" phase. For Mo-50 %S edges, S-bridge structures with 3 periodicity along the edge are the most stable, compatible with aP eierls' distortion arising from the d-bands of the edge Mo atoms.A na dditional explanation for this periodicity is proposed through the formation of 3center bonds.Supporting information and the ORCID identification number(s) for the author(s) of this articlecan be found under: https://doi.

Density Functional Theory Study of Edge-Induced Atomic-Scale Structural Phase Transitions of MoS2 Nanocrystals: Implications for a High-Performance Catalyst

“…First, we compared the stability of 2H S-edge MoS 2 triangular nanocrystals ( n = 6, 100% S coverage) with various edge S-dimer configurations. There are several theoretical studies on the edge S structures of the 2H MoS 2 nanoribbons or triangular nanocrystals. − In these studies, it was mentioned that the S-edge with 100% S coverage is stable and S dimerization is the key factor in stabilizing the structure of MoS 2 . However, there was no detailed study on the number and the position of S dimerization occurring at the edge of the 2H S-edge MoS 2 nanocrystals.…”

Passivation principle of deep-level defects: a study of SnZn defects in kesterites for high-efficient solar cells

“…The molecular orbital interaction (MOI) theory 24,25 indicates that the closer the energy distance of atomic levels, the stronger their coupling, which can split the original deep-level into a decreased bonding state and a raised anti-bonding state. Moreover, the OEC rule 26,27 commonly realized at surfaces by atomic reconstruction, 28,29 at edges by pseudohydrogen saturation 30,31 and at grain boundaries by element doping 26,27 can successfully guide the saturation of unpaired electrons in most covalent semiconductors, resulting in the initial unpaired electrons falling near the VBM. Therefore, the feasibility of the passivation principle with the combination of the strong orbital coupling and the OEC rule at the defect site is examined in this work through external anion doping.…”

Adsorption on Metallic Edges of Transition Metal Dichalcogenides

“…M‐edges are well studied [ 16–18,20 ] and their thermodynamic stability is also present in nanostructures fabricated with more recent methods. [ 30 ] There are also interesting recent reports of other potentially favored reconstructions at high temperatures [ 31 ] and even phase transitions, e.g., from semiconducting 2H to metallic 1T and induced by charge, [ 32 ] electrostatic gating, [ 33 ] or very small nanoribbon width, [ 34 ] but in this letter we present results only for the M‐edges previously examined. [ 20 ] Our density functional theory results for the adsorption energy, the electronic density of states and the band structure for different adsorbate coverages are compared with the corresponding 2D materials.…”