TY - JOUR

T1 - First-principles study on stability, structural and electronic properties of monolayers and nanotubes based on pure Mo(W)S(Se)2 and mixed (Janus) Mo(W)SSe dichalcogenides

AU - Evarestov, R. A.

AU - Kovalenko, A.V.

AU - Bandura, A. V.

N1 - Publisher Copyright: © 2019 Elsevier B.V.

PY - 2020/1

Y1 - 2020/1

N2 - Hybrid density functional theory calculations are performed for the first time to compare the stability, structural and electronic properties of monolayers and single-wall nanotubes based on pure Mo(W)S(Se)(2) and mixed (Janus) Mo(W)SSe dichalcogenides. The stability, structural and electronic properties of Mo and W dichalcogenide nanotubes have been compared at different wall compositions, chiralities and diameters using the same calculation scheme. Different types of mixed nanotubes are considered - with S or Se atoms on the outer (inner) oval shell of the nanotube. It was found that nanotubes Se(out)WS(in) with average diameter (D-avr) greater than approximate to 40 angstrom have the negative strain energy. Our calculations show that the band gap is direct for zigzag MS2 and S (out)MSe(in) nanotubes (M = Mo, W) but it becomes indirect in armchair nanotubes. For the MSe2 and Se(out) MS(in) nanotubes of both chiralities, the band gap is mostly direct, except the armchair tubes with D-avr < 18 A and zigzag tubes with D-avr in interval from 18 to 26 angstrom where it is indirect.

AB - Hybrid density functional theory calculations are performed for the first time to compare the stability, structural and electronic properties of monolayers and single-wall nanotubes based on pure Mo(W)S(Se)(2) and mixed (Janus) Mo(W)SSe dichalcogenides. The stability, structural and electronic properties of Mo and W dichalcogenide nanotubes have been compared at different wall compositions, chiralities and diameters using the same calculation scheme. Different types of mixed nanotubes are considered - with S or Se atoms on the outer (inner) oval shell of the nanotube. It was found that nanotubes Se(out)WS(in) with average diameter (D-avr) greater than approximate to 40 angstrom have the negative strain energy. Our calculations show that the band gap is direct for zigzag MS2 and S (out)MSe(in) nanotubes (M = Mo, W) but it becomes indirect in armchair nanotubes. For the MSe2 and Se(out) MS(in) nanotubes of both chiralities, the band gap is mostly direct, except the armchair tubes with D-avr < 18 A and zigzag tubes with D-avr in interval from 18 to 26 angstrom where it is indirect.

KW - Dichalcogenide bulk crystals

KW - Dichalcogenide monolayers

KW - Electronic band structure

KW - HSE06 exchange-correlation functional

KW - Janus MoSSe and WSSe nanotubes

KW - Strain energy

KW - TRANSITION

KW - GROWTH

KW - RELATIVISTIC EFFECTIVE POTENTIALS

KW - SPIN-ORBIT OPERATORS

KW - MOSE2

UR - http://www.scopus.com/inward/record.url?scp=85070500395&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/0bbaa309-eb79-3652-9d0b-ec2dd646141c/

U2 - 10.1016/j.physe.2019.113681

DO - 10.1016/j.physe.2019.113681

M3 - Article

AN - SCOPUS:85070500395

VL - 115

JO - Physica E: Low-Dimensional Systems and Nanostructures

JF - Physica E: Low-Dimensional Systems and Nanostructures

SN - 1386-9477

M1 - 113681

ER -