Graphene
Nucleation from Amorphous Nickel Carbides: QM/MD Studies on the Role
of Subsurface Carbon Density
Menggai Jiao
Hujun Qian
Alister Page
Kai Li
Ying Wang
Zhijian Wu
Stephan Irle
Keiji Morokuma
10.1021/jp4123612.s002
https://acs.figshare.com/articles/journal_contribution/Graphene_Nucleation_from_Amorphous_Nickel_Carbides_QM_MD_Studies_on_the_Role_of_Subsurface_Carbon_Density/2289271
The mechanism and kinetics of graphene
formation from amorphous nickel carbides have been investigated employing
quantum chemical molecular dynamics (QM/MD) simulations. Amorphous
Ni<sub>3</sub>C, Ni<sub>2</sub>C, and NiC were employed to elucidate
the role of the subsurface carbon density (ρ<sub>C</sub>) on
graphene formation. In each case, the nickel carbide phase underwent
rapid carbon precipitation, resulting in a segregated nickel–carbon
structure. The kinetics of graphene formation was most favorable for
high carbon densities. At low ρ<sub>C</sub>, i.e., Ni<sub>3</sub>C and Ni<sub>2</sub>C, there was a tendency for the formation of
a number of small carbon fragments that failed to coalesce due to
their inability to diffuse over the nickel surface. Graphene formation
was only observed in the presence of high carbon densities that were
relatively localized. These simulations, therefore, suggest that graphene
nucleation is not immediately related to the presence of catalyst
carbide phases.
2014-05-22 00:00:00
presence
kinetic
Subsurface Carbon DensityThe mechanism
Amorphous Nickel Carbides
graphene formation
Amorphous Ni 3C Ni 2C
carbon densities
Graphene
density
simulation
catalyst carbide phases
nickel carbide phase
QM