title: Stable containment of radionuclides on the nanoscale by cut single-wall carbon nanotubes.
abstract: The physisorption of radiolabeled (125)I(-) ions from aqueous solution and the Brunauer-Emmett-Teller (BET) surface areas of various carbonaceous materials [HiPco single-wall carbon nanotubes (SWNTs), F-SWNTs, cut SWNTs, charcoal, graphite, F-graphite and C(60)] have been measured and compared. By far, cut SWNTs (mainly 20-50 nm lengths) displayed the largest surface area of the materials (1180 m(2).g(-1)), being approximately double that of uncut SWNT and charcoal. At low concentrations of (125)I(-), nearly all of the (125)I(-) was adsorbed from aqueous solution within 1 min at room temperature by the cut SWNTs, uncut SWNTs, and charcoal; the other materials showed much less adsorption under the same conditions. Once adsorbed, the (125)I(-) wash-off rate by pure water was highly variable but was especially slow for cut SWNTs (t(1/2) approximately 2720 h) compared to the other materials; wash-off of (125)I(-) by an aqueous H(2)O(2) solution was even slower (t(1/2) approximately 14 300 h). Taken together, these data demonstrate the greatly increased surface area and dramatically enhanced retention properties of cut SWNTs over uncut SWNTs.
authors.affiliation: Department of Chemistry, Center for Nanoscale Science and Technology, and Center for Biological and Environmental Nanotechnology, MS-60, Rice University, 6100 Main Street, Houston, TX 77251-1892, USA.
authors.forename: Yuri A
authors.initials: YA
authors.lastname: Mackeyev
authors.forename: John W
authors.initials: JW
authors.lastname: Marks
authors.forename: Michael G
authors.initials: MG
authors.lastname: Rosenblum
authors.forename: Lon J
authors.initials: LJ
authors.lastname: Wilson
mesh_terms: D000327:Adsorption; D002606:Charcoal / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000737:chemistry; D007457:Iodine Radioisotopes / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D011868:Radioisotopes / Q000737:chemistry*; D012974:Sodium Iodide / Q000737:chemistry; D012996:Solutions / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D007457:Iodine Radioisotopes; D037742:Nanotubes, Carbon; D011868:Radioisotopes; D012996:Solutions; D014867:Water; D002606:Charcoal; D006861:Hydrogen Peroxide; D012974:Sodium Iodide