We use molecular dynamic simulations to study the pressure-driven transport of water molecules through nanoporous graphene and MoS₂ membranes respectively. Our simulation setup comprises one layer of the membrane separating the whole system into two parts filled with pure water. The pressure is provided by a graphene piston which drives the water flow through the nanopore. The flux is monitored at different pore areas ranging from 20 to 360 Angstrom² and is apparently different from the continuum hydrodynamic flow. In particular, due to the absorption layer reducing the effective flow area, the flux in the Mo-domination nanopore is much smaller than the other types of pores. Further, the influence of pressure on flux is also inspected and a proportional relation is found to be signifi...[ Read more ]

We use molecular dynamic simulations to study the pressure-driven transport of water molecules through nanoporous graphene and MoS₂ membranes respectively. Our simulation setup comprises one layer of the membrane separating the whole system into two parts filled with pure water. The pressure is provided by a graphene piston which drives the water flow through the nanopore. The flux is monitored at different pore areas ranging from 20 to 360 Angstrom² and is apparently different from the continuum hydrodynamic flow. In particular, due to the absorption layer reducing the effective flow area, the flux in the Mo-domination nanopore is much smaller than the other types of pores. Further, the influence of pressure on flux is also inspected and a proportional relation is found to be significant between pressure and flux. To determine the inner atom effect in these nanopores, the potential and density distribution in x-y direction was exhibited, which proves the layering phenomenon of water molecules in Mo-domination pores. The potential of mean force tendency in z direction reveals the energy barriers for these four different pores and is in agreement with the flux difference we observed. It can be concluded that these characteristics of nanoporous membranes due to electric interactions between the water molecules and the inner atoms, which changes the structure of the water layer, and this needs further study in future pore boundary design.