Ion transport controlled by nanoparticle-functionalized membranes

Journal Article · Wed Dec 17 04:00:00 EST 2014 · Nature Communications

DOI:https://doi.org/10.1038/ncomms6847· OSTI ID:1392576

Barry, Edward; McBride, Sean P.; Jaeger, Heinrich M.; Lin, Xiao-Min

From proton exchange membranes in fuel cells to ion channels in biological membranes, the well-specified control of ionic interactions in confined geometries profoundly influences the transport and selectivity of porous materials. Here we outline a versatile new approach to control a membrane's electrostatic interactions with ions by depositing ligand-coated nanoparticles around the pore entrances. Leveraging the flexibility and control by which ligated nanoparticles can be synthesized, we demonstrate how ligand terminal groups such as methyl, carboxyl and amine can be used to tune the membrane charge density and control ion transport. Further functionality, exploiting the ligands as binding sites, is demonstrated for sulfonate groups resulting in an enhancement of the membrane charge density. We then extend these results to smaller dimensions by systematically varying the underlying pore diameter. As a whole, these results outline a previously unexplored method for the nanoparticle functionalization of membranes using ligated nanoparticles to control ion transport.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: USDOE Office of Science - Office of Basic Energy Sciences
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 1392576
• Journal Information: Nature Communications, Journal Name: Nature Communications Vol. 5; ISSN 2041-1723
• Publisher: Nature Publishing Group
• Country of Publication: United States
• Language: English