Strained hexagonal boron nitride: Phonon shift and Grüneisen parameter

Ch Androulidakis, E. N. Koukaras, M. Poss, K. Papagelis, C. Galiotis, Sameh H Tawfick

Research output: Contribution to journalArticle

Abstract

Owing to its large electric band gap, two-dimensional (2D) hexagonal boron nitride (hBN) is a very promising candidate for making atomically thin flexible devices. Further, its high mechanical strength makes it suitable as a reinforcing material in composites. It is thus of great interest to study the strain-induced phonon shift of mechanically exfoliated hBN of various thicknesses under tension. It is found that splitting of the E2g phonon to two subpeaks due to the lifting of degeneracy under uniaxial loading occurs at low strain level with average shift rates of -8.4(1.0)cm-1/% and -25.2(1.5)cm-1/% for the E2g+ and E2g-, respectively. These large redshifts of the E2g modes with strain are close to the values obtained from graphene and confirm the high stiffness of 2D hBN. Furthermore, the measured E2g mode Grüneisen parameter is about 1.88 (2), in agreement with the values obtained by classical molecular dynamics (MD) and ab initio MD simulations. The shift rates are similar for hBN with thickness of two to four layers, which is in contrast with graphene, indicating the effective load transfer between the hBN layers. The present results provide useful insights for the use of hBN in electronic devices, 2D heterostructures, and also as a reinforcing agent in composite materials.

Original languageEnglish (US)
Article number241414
JournalPhysical Review B
Volume97
Issue number24
DOIs
StatePublished - Jun 29 2018

Fingerprint

Boron nitride
boron nitrides
shift
Graphite
Graphene
Molecular dynamics
graphene
reinforcing materials
molecular dynamics
composite materials
Composite materials
Strength of materials
Heterojunctions
boron nitride
stiffness
Energy gap
Stiffness
Computer simulation
electronics
simulation

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this

Androulidakis, C., Koukaras, E. N., Poss, M., Papagelis, K., Galiotis, C., & Tawfick, S. H. (2018). Strained hexagonal boron nitride: Phonon shift and Grüneisen parameter. Physical Review B, 97(24), [241414]. https://doi.org/10.1103/PhysRevB.97.241414

Strained hexagonal boron nitride : Phonon shift and Grüneisen parameter. / Androulidakis, Ch; Koukaras, E. N.; Poss, M.; Papagelis, K.; Galiotis, C.; Tawfick, Sameh H.

In: Physical Review B, Vol. 97, No. 24, 241414, 29.06.2018.

Research output: Contribution to journalArticle

Androulidakis, C, Koukaras, EN, Poss, M, Papagelis, K, Galiotis, C & Tawfick, SH 2018, 'Strained hexagonal boron nitride: Phonon shift and Grüneisen parameter', Physical Review B, vol. 97, no. 24, 241414. https://doi.org/10.1103/PhysRevB.97.241414
Androulidakis C, Koukaras EN, Poss M, Papagelis K, Galiotis C, Tawfick SH. Strained hexagonal boron nitride: Phonon shift and Grüneisen parameter. Physical Review B. 2018 Jun 29;97(24). 241414. https://doi.org/10.1103/PhysRevB.97.241414
Androulidakis, Ch ; Koukaras, E. N. ; Poss, M. ; Papagelis, K. ; Galiotis, C. ; Tawfick, Sameh H. / Strained hexagonal boron nitride : Phonon shift and Grüneisen parameter. In: Physical Review B. 2018 ; Vol. 97, No. 24.
@article{1d4ec7d1cdc744149b2cc7589d0ebd47,
title = "Strained hexagonal boron nitride: Phonon shift and Gr{\"u}neisen parameter",
abstract = "Owing to its large electric band gap, two-dimensional (2D) hexagonal boron nitride (hBN) is a very promising candidate for making atomically thin flexible devices. Further, its high mechanical strength makes it suitable as a reinforcing material in composites. It is thus of great interest to study the strain-induced phonon shift of mechanically exfoliated hBN of various thicknesses under tension. It is found that splitting of the E2g phonon to two subpeaks due to the lifting of degeneracy under uniaxial loading occurs at low strain level with average shift rates of -8.4(1.0)cm-1/{\%} and -25.2(1.5)cm-1/{\%} for the E2g+ and E2g-, respectively. These large redshifts of the E2g modes with strain are close to the values obtained from graphene and confirm the high stiffness of 2D hBN. Furthermore, the measured E2g mode Gr{\"u}neisen parameter is about 1.88 (2), in agreement with the values obtained by classical molecular dynamics (MD) and ab initio MD simulations. The shift rates are similar for hBN with thickness of two to four layers, which is in contrast with graphene, indicating the effective load transfer between the hBN layers. The present results provide useful insights for the use of hBN in electronic devices, 2D heterostructures, and also as a reinforcing agent in composite materials.",
author = "Ch Androulidakis and Koukaras, {E. N.} and M. Poss and K. Papagelis and C. Galiotis and Tawfick, {Sameh H}",
year = "2018",
month = "6",
day = "29",
doi = "10.1103/PhysRevB.97.241414",
language = "English (US)",
volume = "97",
journal = "Physical Review B",
issn = "2469-9950",
publisher = "American Physical Society",
number = "24",

}

TY - JOUR

T1 - Strained hexagonal boron nitride

T2 - Phonon shift and Grüneisen parameter

AU - Androulidakis, Ch

AU - Koukaras, E. N.

AU - Poss, M.

AU - Papagelis, K.

AU - Galiotis, C.

AU - Tawfick, Sameh H

PY - 2018/6/29

Y1 - 2018/6/29

N2 - Owing to its large electric band gap, two-dimensional (2D) hexagonal boron nitride (hBN) is a very promising candidate for making atomically thin flexible devices. Further, its high mechanical strength makes it suitable as a reinforcing material in composites. It is thus of great interest to study the strain-induced phonon shift of mechanically exfoliated hBN of various thicknesses under tension. It is found that splitting of the E2g phonon to two subpeaks due to the lifting of degeneracy under uniaxial loading occurs at low strain level with average shift rates of -8.4(1.0)cm-1/% and -25.2(1.5)cm-1/% for the E2g+ and E2g-, respectively. These large redshifts of the E2g modes with strain are close to the values obtained from graphene and confirm the high stiffness of 2D hBN. Furthermore, the measured E2g mode Grüneisen parameter is about 1.88 (2), in agreement with the values obtained by classical molecular dynamics (MD) and ab initio MD simulations. The shift rates are similar for hBN with thickness of two to four layers, which is in contrast with graphene, indicating the effective load transfer between the hBN layers. The present results provide useful insights for the use of hBN in electronic devices, 2D heterostructures, and also as a reinforcing agent in composite materials.

AB - Owing to its large electric band gap, two-dimensional (2D) hexagonal boron nitride (hBN) is a very promising candidate for making atomically thin flexible devices. Further, its high mechanical strength makes it suitable as a reinforcing material in composites. It is thus of great interest to study the strain-induced phonon shift of mechanically exfoliated hBN of various thicknesses under tension. It is found that splitting of the E2g phonon to two subpeaks due to the lifting of degeneracy under uniaxial loading occurs at low strain level with average shift rates of -8.4(1.0)cm-1/% and -25.2(1.5)cm-1/% for the E2g+ and E2g-, respectively. These large redshifts of the E2g modes with strain are close to the values obtained from graphene and confirm the high stiffness of 2D hBN. Furthermore, the measured E2g mode Grüneisen parameter is about 1.88 (2), in agreement with the values obtained by classical molecular dynamics (MD) and ab initio MD simulations. The shift rates are similar for hBN with thickness of two to four layers, which is in contrast with graphene, indicating the effective load transfer between the hBN layers. The present results provide useful insights for the use of hBN in electronic devices, 2D heterostructures, and also as a reinforcing agent in composite materials.

UR - http://www.scopus.com/inward/record.url?scp=85049691568&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85049691568&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.97.241414

DO - 10.1103/PhysRevB.97.241414

M3 - Article

AN - SCOPUS:85049691568

VL - 97

JO - Physical Review B

JF - Physical Review B

SN - 2469-9950

IS - 24

M1 - 241414

ER -