Structure, property and transport mechanism of water and electrolytes in graphene nanopores
type: CreativeWork
description: Advances in fabrication, measurement and characterization have led to intense research in the area of nanoporous membranes. Owing to its ultrathin thickness, graphene nanopores are promising candidates for various applications such as water desalination, single molecule sensing, etc. Understanding water and ion transport mechanisms and properties in membranes is essential to characterize and design membranes for various applications mentioned above. In nanopores, transport mechanisms can differ from the continuum theory and transport properties under confinement can be different from the bulk values. In such a situation, molecular dynamics simulation is a useful tool to observe molecular level details. In this thesis, structure, properties and transport mechanism of water and ions in graphene nanopores are investigated in detail to realize the full potential of graphene nanopores, using molecular dynamics simulations. Due to the unique water structure, confined in the radial direction and layered in the axial direction of the pore, water viscosity and slip length increase with a decrease in the pore radius, in contrast to water confined in a carbon nanotube. Due to the nanometer dimension of the pore, Reynolds number for pressure-driven water flow through graphene nanopores is very small and a linear relation between flow rate and applied pressure drop is observed. Hydrodynamic membrane length is introduced to effectively capture entrance and exit pressure losses. As the diameter of the pore increases, the water transport mechanism transitions from collective diffusion to frictional flow described by the modified Hagen–Poiseuille equation. Graphene membrane is shown to be ultra-efficient by comparing the permeation coefficient of graphene membrane to that of advanced membranes. Water transport through graphene is compared with water transport through thin carbon nanotube (CNT) membranes. For smaller diameter membranes, where single-file structure is observed, water …
abstract: Advances in fabrication, measurement and characterization have led to intense research in the area of nanoporous membranes. Owing to its ultrathin thickness, graphene nanopores are promising candidates for various applications such as water desalination, single molecule sensing, etc. Understanding water and ion transport mechanisms and properties in membranes is essential to characterize and design membranes for various applications mentioned above. In nanopores, transport mechanisms can differ from the continuum theory and transport properties under confinement can be different from the bulk values. In such a situation, molecular dynamics simulation is a useful tool to observe molecular level details. In this thesis, structure, properties and transport mechanism of water and ions in graphene nanopores are investigated in detail to realize the full potential of graphene nanopores, using molecular dynamics simulations. Due to the unique water structure, confined in the radial direction and layered in the axial direction of the pore, water viscosity and slip length increase with a decrease in the pore radius, in contrast to water confined in a carbon nanotube. Due to the nanometer dimension of the pore, Reynolds number for pressure-driven water flow through graphene nanopores is very small and a linear relation between flow rate and applied pressure drop is observed. Hydrodynamic membrane length is introduced to effectively capture entrance and exit pressure losses. As the diameter of the pore increases, the water transport mechanism transitions from collective diffusion to frictional flow described by the modified Hagen–Poiseuille equation. Graphene membrane is shown to be ultra-efficient by comparing the permeation coefficient of graphene membrane to that of advanced membranes. Water transport through graphene is compared with water transport through thin carbon nanotube (CNT) membranes. For smaller diameter membranes, where single-file structure is observed, water …
author: Suk, Myung eun
language: en
keywords: Nanofluidics, Molecular dynamics simulation, Membrane transport
date published: 2013-08-22T16:56:25Z
date modified: 2026-07-22T22:25:36Z
provider: University of Illinois - Urbana-Champaign
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Illinois at Urbana-Champaign

PropertyValue
property ID: Handle
value: http://hdl.handle.net/2142/45641