Water Desalination using Nano-Porous Graphene Membrane: Non-Equilibrium Molecular Dynamics Study
Mentor: Dr. Eunsu Paek
Department: Chemical and Biomolecular Engineering
Desalination of brackish water and seawater has become extremely important due to global water scarcity in recent years. As such, it is imperative to develop revolutionary and energy-efficient desalination technology and materials that can significantly reduce the overall cost and electricity usage. Nanoporous graphene (NPG) membranes have been recently proposed as a next-generation membrane material for reverse osmosis (RO) technique to replace traditional polyamide thin-film composite membrane, yet the fundamental understanding in nanoscale is still largely lacking. In this project, the participant will investigate the novel NPG membrane and study the flow of water and ions through the NPG membrane using non-equilibrium molecular dynamics (NEMD) simulations. The participating student will first learn about classical molecular dynamics simulations using a Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS) package; simple practice problems will be given to them. After that, the participant will contribute to (i) development of a RO model system using NEMD with varying external pressures (ii) investigation of hydrogen-bonding network of water molecules during water passage (iii) interplay between solvation and desolvation of salt ions as they pass through the membrane (ix) water flux and salt rejection. After this stage, the framework can be extended to different pore sizes and functional groups.