Unexpected Epitaxial Growth of a Few WS₂ Layers on {11̅00} Facets of ZnO Nanowires

Abstract

Core–shell nanowires are an interesting and perspective class of radially heterostructured nanomaterials where epitaxial growth of the shell can be realized even at noticeable core–shell lattice mismatch. In this study epitaxial hexagonally shaped shell consisting of WS2 nanolayers was grown on {11̅00} facets of prismatic wurtzite-structured [0001]-oriented ZnO nanowires for the first time. A synthesis was performed by annealing in a sulfur atmosphere of ZnO/WO3 core–shell structures, produced by reactive dc magnetron sputtering of an amorphous a-WO3 layer on top of ZnO nanowire array. The morphology and phase composition of synthesized ZnO/WS2 core–shell nanowires were confirmed by scanning and transmission electron microscopy (SEM and TEM), micro-Raman, and photoluminescence spectroscopy. Epitaxial growth of WS2(0001) layer(s) on {11̅00} facets of ZnO nanowire is unexpected due to incompatibility of their symmetry and structure parameters. To relax the interfacial incoherence, we propose a model of ZnO/WS2 interface containing WS2 bridging groups inside and use first-principles simulations to support its feasibility.

Synthesis and characterization of ZnO/ZnS/MoS2 core-shell nanowires

“…In our previous work [27], no formation of detectable ZnS layer was observed after the synthesis of ZnO/WS 2 core-shell NWs at 800 °C, and ZnO core remained unaltered and single crystalline after the growth of WS 2 shell (Supplementary materials, Fig. S3).…”

More features, more tools, moreCrysTBox

“…This capability is combined with a high degree of automation, eliminating much of the effort associated with manual processing of data. These factors have led to a number of successful applications (Klinger et al, 2016;Gartnerova et al, 2017;Steele et al, 2016;Polyakov et al, 2016;Butanovs et al, 2017;Singh et al, 2017;Zhao et al, 2016).…”

Ab Initio Calculations on the Electronic Structure and Photocatalytic Properties of Two‐Dimensional WS2 (0001) Nanolayers of Varying Thickness

“…Hybrid DFT calculations using CO LCAO formalism (crystalline orbitals as linear combination of atomic orbitals) were performed in that study as well, to verify the corresponding experimental data including parameters of weak physisorption for 2–5 ML WS 2 shells upon the ZnO NW core. Although TMDC deposition above the supporting substrate was often considered, no deep analysis of its influence on the properties of nanolayers was performed so far (it was only mentioned that such an influence is rather weak).…”

“…Changes of their electronic structure were estimated by emerging photoluminescence. Additionally, nanothin films consisting of a few WS 2 MLs were experimentally observed to grow upon [0001]-oriented ZnO nanowires, [24] formation of which was confirmed using the methods of transmission electron microscopy, Raman scattering, and optical spectroscopy. Hybrid DFTcalculations using CO LCAO formalism (crystalline orbitals as linear combination of atomic orbitals) were performed in that study as well, to verify the corresponding experimental data including parameters of weak physisorption for 2-5 ML WS 2 shells upon the ZnO NW core.…”

“…[41] The primitive unit cell of 2H c WS 2 phase consists of two atomic inversely arranged layers containing three atomic planes each, see ref. [24] and Figure 1. Inner planes of each layer contain only W atoms while in its turn outer planes contain S atoms.…”