Δημοσιεύσεις

Project Acronym: Q2D-2
Title: Density-functional theory studies on two-dimensional (2D), quasi-2D, and layered materials
Affiliation: national technical university of athens
Pi: Tsetseris Leonidas
Research Field: chemical sciences and materials

Two-dimensional thio- and seleno-cyanates of Mo and W
by C Boukouvala, D Kaltsas and L Tsetseris
Abstract:
The stability of two-dimensional (2D) transition metal di-chalcogenides (TMDC) is controlled by the fact that sulfur or selenium atoms can cap the 2D layers without exposing highly reactive bonds. Here we use first-principles calculations to show that a similar structural motif can stabilize Mo- and W-based 2D materials with thio- or seleno-cyanate groups. In particular, we show that the formation of Mo(SeCN) 2 , W(SCN) 2 and W(SeCN) 2 sheets is energetically favorable and can lead to various configurations that resemble the well-known polymorphs of TMDCs. The lowest-energy structures are small-gap semiconductors, while certain polytypes bear Dirac-like cones close to the Fermi energy, demonstrating the potential of these new 2D materials for applications in modern electronic devices.
Reference:
Two-dimensional thio- and seleno-cyanates of Mo and W (C Boukouvala, D Kaltsas and L Tsetseris), In Journal of Physics: Condensed Matter, volume 29, 2017.
Bibtex Entry:
@article{0953-8984-29-48-485703,
 author = {C Boukouvala and D Kaltsas and L Tsetseris},
 title = {Two-dimensional thio- and seleno-cyanates of Mo and W},
 journal = {Journal of Physics: Condensed Matter},
 volume = {29},
 number = {48},
 pages = {485703},
 doi = {10.1088/1361-648X/aa9538},
 url = {http://stacks.iop.org/0953-8984/29/i=48/a=485703},
 year = {2017},
 bibyear = {2017},
 abstract = {The stability of two-dimensional (2D) transition metal di-chalcogenides (TMDC) is controlled by the fact that sulfur or selenium atoms can cap the 2D layers without exposing highly reactive bonds. Here we use first-principles calculations to show that a similar structural motif can stabilize Mo- and W-based 2D materials with thio- or seleno-cyanate groups. In particular, we show that the formation of Mo(SeCN) 2 , W(SCN) 2 and W(SeCN) 2 sheets is energetically favorable and can lead to various configurations that resemble the well-known polymorphs of TMDCs. The lowest-energy structures are small-gap semiconductors, while certain polytypes bear Dirac-like cones close to the Fermi energy, demonstrating the potential of these new 2D materials for applications in modern electronic devices.},
}