TY  - JOUR
A1  - Mortazavi, Bohayra
A1  - Pereira, Luiz Felipe C.
A1  - Jiang, Jin-Wu
A1  - Rabczuk, Timon
T1  - Modelling heat conduction in polycrystalline hexagonal boron-nitride films
JF  - Scientific Reports
N2  - We conducted extensive molecular dynamics simulations to investigate the thermal conductivity of polycrystalline hexagonal boron-nitride (h-BN) films. To this aim, we constructed large atomistic models of polycrystalline h-BN sheets with random and uniform grain configuration. By performing equilibrium molecular dynamics (EMD) simulations, we investigated the influence of the average grain size on the thermal conductivity of polycrystalline h-BN films at various temperatures. Using the EMD results, we constructed finite element models of polycrystalline h-BN sheets to probe the thermal conductivity of samples with larger grain sizes. Our multiscale investigations not only provide a general viewpoint regarding the heat conduction in h-BN films but also propose that polycrystalline h-BN sheets present high thermal conductivity comparable to monocrystalline sheets.
KW  - Wärmeleitfähigkeit
KW  - Bornitrid
KW  - Finite-Elemente-Methode
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20170425-31534
ER  - 
TY  - JOUR
A1  - Noori, Hamidreza
A1  - Mortazavi, Bohayra
A1  - Keshtkari, Leila
A1  - Zhuang, Xiaoying
A1  - Rabczuk, Timon
T1  - Nanopore creation in  MoS2 and graphene monolayers  by nanoparticles impact: a reactive molecular dynamics study
JF  - Applied Physics A
N2  - In this work, extensive reactive molecular dynamics simulations are conducted to analyze the nanopore creation by nano-particles impact over single-layer molybdenum disulfide  (MoS2) with 1T and 2H phases. We also compare the results with graphene monolayer. In our simulations, nanosheets are exposed to a spherical rigid carbon projectile with high initial velocities ranging from 2 to 23 km/s. Results for three different structures are compared to examine the most critical factors in the perforation and resistance force during the impact. To analyze the perforation and impact resistance, kinetic energy and displacement time history of the projectile as well as perforation resistance force of the projectile are investigated. 
Interestingly, although the elasticity module and tensile strength of the graphene are by almost five times higher than those of   MoS2, the results demonstrate that 1T and 2H-MoS2 phases are more resistive to the impact loading and perforation than graphene. For the  MoS2nanosheets, we realize that the 2H phase is more resistant to impact loading than the 1T counterpart. 
Our reactive molecular dynamics results highlight that in addition to the strength and toughness, atomic structure is another crucial factor that can contribute substantially to impact resistance of 2D materials. The obtained results can be useful to guide the experimental setups for the nanopore creation in  MoS2or other 2D lattices.
KW  - Nanomechanik
KW  - Molekülstruktur
KW  - Nanoporöser Stoff
KW  - MoS2
KW  - molecular dynamics
KW  - Nanopore
KW  - Graphene
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:gbv:wim2-20210804-44756
UR  - https://link.springer.com/article/10.1007/s00339-021-04693-5
VL  - 2021
IS  - volume 127, article 541
SP  - 1
EP  - 13
PB  - Springer
CY  - Heidelberg
ER  -