First-principles density functional theory calculations are performed in one-dimensional single-layer WS2 nanoribbons with zigzag- and armchair-edges. Magnetic ordering, optical response, and chemical reactivity are investigated. Our results demonstrated thatWS2 zigzag nanoribbons exhibit a ferromagnetic- metallic behavior that is attributed to the edges; the resulting magnetic moments are mainly localized in S andWedge atoms. Furthermore, the magnetic ordering along the edges depends on the zigzag nanoribbon's width. Armchair nanoribbons exhibit semiconducting behavior. Optical response results demonstrated that there exists a strong optical polarization anisotropy enhancing a well defined absorption intensity peak, with polarization along the nanoribbons axis. Regarding chemical reactivity, ribbons are exposed to water (H2O), thiophene (C4H4S), and carbon monoxide (CO) molecules. Results reveal thatH2Ocan be covalently joined to the edges via the W-Atoms in the ribbons with zigzag-edges, whereas in ribbons with armchair edges,H2Ois dissociated inOHand H, and these species are joined toWand S atoms respectively. Results for thiophene on zigzag nanoribbons demonstrated thatC4H4S molecules are absorbed by W-terminated edges, whereas in armchair ribbons, theC4H4S is linked to the edges by binding to the sulfur. Interestingly,COmolecules give rise to half-metallicity and surprising ferromagnetism in zigzag and armchair nanoribbons, respectively. The results discussed here could help to understand the physical and chemical properties of edges in transition metal dichalcogenides materials.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering