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S. Majidi et al.
and Monte Carlo (MC) simulation. In the MD simulation as a deterministic method,
Newton equations of motion are solved for a system containing N particles, which
interact through a force field, to explain the time evolution of the system. The macroscopic properties of the system can be calculated from its microscopic actions using
the statistical mechanics and considering the trajectories of particles provided by the
MD simulation at molecular level [63]. In the MC simulation, particles are moved
randomly to represent a target probability distribution conforming to the desired state
of the system. Therefore, MC calculates statistical thermodynamic probabilities of
acceptance/rejection of moves [64].
Recently, MD simulations have been widely conducted to investigate the
membrane separation processes [65]. This could play a considerable role in the
prediction of 2D nanoporous materials capability in water desalination and adsorption performance of materials at the molecular level [66, 67]. Furthermore, due to
the quantities computing connected to the system dynamics such as time-dependent
fluctuations and transport coefficients, the MD method has benefits compared to
other computational techniques [68].
3.1 Simulation of h-BN Membrane Filtration for Water
Purification
Fnding of new ways to modify the performance of water desalination methods
and diminish the capital and operating expenditures is a major issue in scientific
researches [69]. The molecular simulations can prepare a novel insight, not available
from experiments, which presents keys to the extension of new separation methods
[70]. Garnier et al. [71] attempted to connect interfacial properties to water transfer
across the BN and graphene membranes. They studied the surface tension of water
on the graphene and BN surfaces using MD simulations. The local surface tension
of water on the membranes was determined, which can be seen in Fig. 1. The results
showed smaller surface tension on BN (7 mN.m
−1 ) in comparison with graphene (40
mN.m
−1 ), which leads to superior wetting of water on BN. They found that more
desirable interactions between water molecules and atoms on BN membrane (B and
N atoms) resulted in smaller surface tension on BN surface compared to graphene
surface.
The pressure-driven MD simulations were carried out to comprise the pure
water transfer across the nanoporous BN and graphene membranes. A nanopore
with a diameter of 7 Å and a surface area of 67.2 Å
2 was carved in BN and
graphene membranes. The results revealed that under the same condition, nanoporous
BN possesses higher water permeability than graphene as shown in Fig. 2. The
obvious gap in the surface tension influenced directly the water permeability across
nanoporous membranes due to superior wetting, which enhances water molecule
passage through the nanopore of BN membrane.
S. Majidi et al.
and Monte Carlo (MC) simulation. In the MD simulation as a deterministic method,
Newton equations of motion are solved for a system containing N particles, which
interact through a force field, to explain the time evolution of the system. The macroscopic properties of the system can be calculated from its microscopic actions using
the statistical mechanics and considering the trajectories of particles provided by the
MD simulation at molecular level [63]. In the MC simulation, particles are moved
randomly to represent a target probability distribution conforming to the desired state
of the system. Therefore, MC calculates statistical thermodynamic probabilities of
acceptance/rejection of moves [64].
Recently, MD simulations have been widely conducted to investigate the
membrane separation processes [65]. This could play a considerable role in the
prediction of 2D nanoporous materials capability in water desalination and adsorption performance of materials at the molecular level [66, 67]. Furthermore, due to
the quantities computing connected to the system dynamics such as time-dependent
fluctuations and transport coefficients, the MD method has benefits compared to
other computational techniques [68].
3.1 Simulation of h-BN Membrane Filtration for Water
Purification
Fnding of new ways to modify the performance of water desalination methods
and diminish the capital and operating expenditures is a major issue in scientific
researches [69]. The molecular simulations can prepare a novel insight, not available
from experiments, which presents keys to the extension of new separation methods
[70]. Garnier et al. [71] attempted to connect interfacial properties to water transfer
across the BN and graphene membranes. They studied the surface tension of water
on the graphene and BN surfaces using MD simulations. The local surface tension
of water on the membranes was determined, which can be seen in Fig. 1. The results
showed smaller surface tension on BN (7 mN.m
−1 ) in comparison with graphene (40
mN.m
−1 ), which leads to superior wetting of water on BN. They found that more
desirable interactions between water molecules and atoms on BN membrane (B and
N atoms) resulted in smaller surface tension on BN surface compared to graphene
surface.
The pressure-driven MD simulations were carried out to comprise the pure
water transfer across the nanoporous BN and graphene membranes. A nanopore
with a diameter of 7 Å and a surface area of 67.2 Å
2 was carved in BN and
graphene membranes. The results revealed that under the same condition, nanoporous
BN possesses higher water permeability than graphene as shown in Fig. 2. The
obvious gap in the surface tension influenced directly the water permeability across
nanoporous membranes due to superior wetting, which enhances water molecule
passage through the nanopore of BN membrane.