Precise and Ultrafast Molecular Sieving Through Graphene Oxide Membranes

  title={Precise and Ultrafast Molecular Sieving Through Graphene Oxide Membranes},
  author={Rakesh K. Joshi and Paola Carbone and F C Wang and Vasyl G. Kravets and Y Su and Irina V. Grigorieva and H. A. Wu and SUPARNA DUTTASINHA and Rahul R. Nair},
  pages={752 - 754}
Graphene oxide membranes allow only very small hydrated molecules and ions to pass with an accelerated transport rate. [Also see Perspective by Mi] Graphene-based materials can have well-defined nanometer pores and can exhibit low frictional water flow inside them, making their properties of interest for filtration and separation. We investigate permeation through micrometer-thick laminates prepared by means of vacuum filtration of graphene oxide suspensions. The laminates are vacuum-tight in… 

Graphene Oxide Membranes for Ionic and Molecular Sieving

  • B. Mi
  • Engineering
  • 2014
It is reported that ions smaller in size than the GO nanochannel can permeate in the GO membrane at a speed orders of magnitude faster than would occur through simple diffusion.

Ultrathin graphene-based membrane with precise molecular sieving and ultrafast solvent permeation.

Efficient and fast filtration of organic solutions through GO laminates containing smooth two-dimensional capillaries made from large (10-20 μm) flakes is reported, which significantly expands possibilities for the use of GO membranes in purification and filTration technologies.

Tunable sieving of ions using graphene oxide membranes.

A simple scalable method is demonstrated to obtain graphene-based membranes with limited swelling, which exhibit 97% rejection for NaCl and decrease exponentially with decreasing sieve size, but water transport is weakly affected.

Ultrafast, Stable Ionic and Molecular Sieving through Functionalized Boron Nitride Membranes.

It is shown that the nanometer-thick membrane prepared by means of filtration of functionalized boron nitride (FBN) water suspensions can block solutes with hydrated radii larger than 4.3 angstroms (Å) in water.

Graphene-based membranes for organic solvent nanofiltration

Different from the conventional polymeric separation membranes having a wide flexible-pore size distribution, layered graphene-based films with interconnected nanochannels provide narrowly

Water/Alcohol Separation in Graphene Oxide Membranes: Insights from Molecular Dynamics and Monte Carlo Simulations

Graphene-based membranes have been investigated as promising candidates for water filtration and gas separation applications. Experimental evidences have shown that graphene oxide can be impermeable

Tunable Ion Sieving of Graphene Membranes through the Control of Nitrogen-Bonding Configuration.

Novel nitrogen-doped graphene (NG) membranes for use in tunable ion sieving that are made via facile fabrication by a time-dependent N-doping technique are proposed.

Ion sieving in graphene oxide membranes via cationic control of interlayer spacing

Here, cationic control of the interlayer spacing of graphene oxide membranes with ångström precision is demonstrated using K+, Na+, Ca2+, Li+ or Mg2+ ions, suggesting that other ions could be used to produce a wider range of interlayer spacings.



Unimpeded Permeation of Water Through Helium-Leak–Tight Graphene-Based Membranes

Submicrometer-thick membranes made from graphene oxide can be completely impermeable to liquids, vapors, and gases, including helium, but these membranes allow unimpeded permeation of water (H2O permeates through the membranes at least 1010 times faster than He).

Selective molecular sieving through porous graphene.

It is shown that ultraviolet-induced oxidative etching can create pores in micrometre-sized graphene membranes, and the resulting membranes can be used as molecular sieves and agree with models based on effusion through a small number of ångstrom-sized pores.

Water desalination across nanoporous graphene.

The results indicate that the water permeability of this material is several orders of magnitude higher than conventional reverse osmosis membranes, and that nanoporous graphene may have a valuable role to play for water purification.

Origin of anomalous water permeation through graphene oxide membrane.

It is shown that formation of hexagonal ice bilayer in between the flakes as well as melting transition of ice at the edges of flakes are crucial to realize the perfect water permeation across the whole stacked structures, highlighting a unique water dynamics in randomly connected two-dimensional spaces.

Enabling graphene oxide nanosheets as water separation membranes.

  • Meng HuB. Mi
  • Engineering
    Environmental science & technology
  • 2013
It is emphasized that the facile synthesis of a GO membrane exploiting the ideal properties of inexpensive GO materials offers a myriad of opportunities to modify its physicochemical properties, potentially making the GO membrane a next-generation, cost-effective, and sustainable alternative to the long-existing thin-film composite polyamide membranes for water separation applications.

Ultrathin Graphene Nanofiltration Membrane for Water Purification

A method of fabricating ultrathin (≈22–53 nm thick) graphene nanofiltration membranes (uGNMs) on microporous substrates is presented for efficient water purification using chemically converted

Selective ion penetration of graphene oxide membranes.

The selective ion penetration and water purification properties of freestanding graphene oxide (GO) membranes are demonstrated and it is revealed that sodium salts can be separated effectively from copper salts and organic contaminants.

Ion exclusion by sub-2-nm carbon nanotube pores

It is shown that carbon nanotube membranes exhibit significant ion exclusion that can be as high as 98% under certain conditions, which strongly support a Donnan-type rejection mechanism, dominated by electrostatic interactions between fixed membrane charges and mobile ions.

Water conduction through the hydrophobic channel of a carbon nanotube

Observations suggest that carbon nanotubes, with their rigid nonpolar structures, might be exploited as unique molecular channels for water and protons, with the channel occupancy and conductivity tunable by changes in the local channel polarity and solvent conditions.

Effect of tip functionalization on transport through vertically oriented carbon nanotube membranes.

Ionic flux through a composite membrane structure, containing vertically aligned carbon nanotubes crossing a polystyrene matrix film, was studied as a function of chemical end groups at the entrance