Diffusion through Carbon Nanotube Semipermeable membranes
The goal of this project is to measure transport through CNTs and study effects of confinement at molecular scale. This work is motivated by several simulation papers in high profile journals that predict significantly higher transport rates of gases and liquids through carbon nanotubes as compared...
Main Author: | |
---|---|
Other Authors: | |
Format: | Report |
Language: | English |
Published: |
Lawrence Livermore National Laboratory
2006
|
Subjects: | |
Online Access: | https://doi.org/10.2172/928189 https://digital.library.unt.edu/ark:/67531/metadc902881/ |
id |
ftunivnotexas:info:ark/67531/metadc902881 |
---|---|
record_format |
openpolar |
spelling |
ftunivnotexas:info:ark/67531/metadc902881 2023-05-15T16:41:39+02:00 Diffusion through Carbon Nanotube Semipermeable membranes Bakajin, O United States. Department of Energy. 2006-02-13 5 p. (0.1 MB) Text https://doi.org/10.2172/928189 https://digital.library.unt.edu/ark:/67531/metadc902881/ English eng Lawrence Livermore National Laboratory rep-no: UCRL-TR-219029 grantno: W-7405-ENG-48 doi:10.2172/928189 osti: 928189 https://digital.library.unt.edu/ark:/67531/metadc902881/ ark: ark:/67531/metadc902881 Neutron Diffraction Biology Carbon Water Confinement Nanotubes Configuration Zeolites Bonding Probes Diffusion Proteins Hydrogen Optimization Desalination Membranes Chemistry Transport Solvation Dialysis 37 Inorganic Organic Physical And Analytical Chemistry Gases Catalysis Report 2006 ftunivnotexas https://doi.org/10.2172/928189 2017-04-15T22:07:44Z The goal of this project is to measure transport through CNTs and study effects of confinement at molecular scale. This work is motivated by several simulation papers in high profile journals that predict significantly higher transport rates of gases and liquids through carbon nanotubes as compared with similarly-sized nanomaterials (e.g. zeolites). The predictions are based on the effects of confinement, atomically smooth pore walls and high pore density. Our work will provide the first measurements that would compare to and hopefully validate the simulations. Gas flux is predicted to be >1000X greater for SWNTs versus zeolitesi. A high flux of 6-30 H2O/NT/ns {approx} 8-40 L/min for a 1cm{sup 2} membrane is also predicted. Neutron diffraction measurements indicate existence of a 1D water chain within a cylindrical ice sheet inside carbon nanotubes, which is consistent with the predictions of the simulation. The enabling experimental platform that we are developing is a semipermeable membrane made out of vertically aligned carbon nanotubes with gaps between nanotubes filled so that the transport occurs through the nanotubes. The major challenges of this project included: (1) Growth of CNTs in the suitable vertically aligned configuration, especially the single wall carbon nanotubes; (2) Development of a process for void-free filling gaps between CNTs; and (3) Design of the experiments that will probe the small amounts of analyte that go through. Knowledge of the behavior of water upon nanometer-scale confinement is key to understanding many biological processes. For example, the protein folding process is believed to involve water confined in a hydrophobic environment. In transmembrane proteins such as aquaporins, water transport occurs under similar conditions. And in fields as far removed as oil recovery and catalysis, an understanding of the nanoscale molecular transport occurring within the nanomaterials used (e.g. zeolites) is the key to process optimization. Furthermore, advancement of many emerging nanotechnologies in chemistry and biology will undoubtedly be aided by an understanding confined water transport, particularly the details of hydrogen bonding and solvation that become crucial on this length scale. We can envision several practical applications for our devices, including desalination, gas separations, dialysis, and semipermeable fabrics for protection against CW agents etc. The single wall carbon nanotube membranes will be the key platform for applications because they will allow high transport rates of small molecules such as water and eliminate solvated ions or CW agents. Report Ice Sheet University of North Texas: UNT Digital Library |
institution |
Open Polar |
collection |
University of North Texas: UNT Digital Library |
op_collection_id |
ftunivnotexas |
language |
English |
topic |
Neutron Diffraction Biology Carbon Water Confinement Nanotubes Configuration Zeolites Bonding Probes Diffusion Proteins Hydrogen Optimization Desalination Membranes Chemistry Transport Solvation Dialysis 37 Inorganic Organic Physical And Analytical Chemistry Gases Catalysis |
spellingShingle |
Neutron Diffraction Biology Carbon Water Confinement Nanotubes Configuration Zeolites Bonding Probes Diffusion Proteins Hydrogen Optimization Desalination Membranes Chemistry Transport Solvation Dialysis 37 Inorganic Organic Physical And Analytical Chemistry Gases Catalysis Bakajin, O Diffusion through Carbon Nanotube Semipermeable membranes |
topic_facet |
Neutron Diffraction Biology Carbon Water Confinement Nanotubes Configuration Zeolites Bonding Probes Diffusion Proteins Hydrogen Optimization Desalination Membranes Chemistry Transport Solvation Dialysis 37 Inorganic Organic Physical And Analytical Chemistry Gases Catalysis |
description |
The goal of this project is to measure transport through CNTs and study effects of confinement at molecular scale. This work is motivated by several simulation papers in high profile journals that predict significantly higher transport rates of gases and liquids through carbon nanotubes as compared with similarly-sized nanomaterials (e.g. zeolites). The predictions are based on the effects of confinement, atomically smooth pore walls and high pore density. Our work will provide the first measurements that would compare to and hopefully validate the simulations. Gas flux is predicted to be >1000X greater for SWNTs versus zeolitesi. A high flux of 6-30 H2O/NT/ns {approx} 8-40 L/min for a 1cm{sup 2} membrane is also predicted. Neutron diffraction measurements indicate existence of a 1D water chain within a cylindrical ice sheet inside carbon nanotubes, which is consistent with the predictions of the simulation. The enabling experimental platform that we are developing is a semipermeable membrane made out of vertically aligned carbon nanotubes with gaps between nanotubes filled so that the transport occurs through the nanotubes. The major challenges of this project included: (1) Growth of CNTs in the suitable vertically aligned configuration, especially the single wall carbon nanotubes; (2) Development of a process for void-free filling gaps between CNTs; and (3) Design of the experiments that will probe the small amounts of analyte that go through. Knowledge of the behavior of water upon nanometer-scale confinement is key to understanding many biological processes. For example, the protein folding process is believed to involve water confined in a hydrophobic environment. In transmembrane proteins such as aquaporins, water transport occurs under similar conditions. And in fields as far removed as oil recovery and catalysis, an understanding of the nanoscale molecular transport occurring within the nanomaterials used (e.g. zeolites) is the key to process optimization. Furthermore, advancement of many emerging nanotechnologies in chemistry and biology will undoubtedly be aided by an understanding confined water transport, particularly the details of hydrogen bonding and solvation that become crucial on this length scale. We can envision several practical applications for our devices, including desalination, gas separations, dialysis, and semipermeable fabrics for protection against CW agents etc. The single wall carbon nanotube membranes will be the key platform for applications because they will allow high transport rates of small molecules such as water and eliminate solvated ions or CW agents. |
author2 |
United States. Department of Energy. |
format |
Report |
author |
Bakajin, O |
author_facet |
Bakajin, O |
author_sort |
Bakajin, O |
title |
Diffusion through Carbon Nanotube Semipermeable membranes |
title_short |
Diffusion through Carbon Nanotube Semipermeable membranes |
title_full |
Diffusion through Carbon Nanotube Semipermeable membranes |
title_fullStr |
Diffusion through Carbon Nanotube Semipermeable membranes |
title_full_unstemmed |
Diffusion through Carbon Nanotube Semipermeable membranes |
title_sort |
diffusion through carbon nanotube semipermeable membranes |
publisher |
Lawrence Livermore National Laboratory |
publishDate |
2006 |
url |
https://doi.org/10.2172/928189 https://digital.library.unt.edu/ark:/67531/metadc902881/ |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_relation |
rep-no: UCRL-TR-219029 grantno: W-7405-ENG-48 doi:10.2172/928189 osti: 928189 https://digital.library.unt.edu/ark:/67531/metadc902881/ ark: ark:/67531/metadc902881 |
op_doi |
https://doi.org/10.2172/928189 |
_version_ |
1766032112102670336 |