Covalent Organic Frameworks as a Decorating Platform for Utilization and Affinity Enhancement of Chelating Sites for Radionuclide Sequestration.

Autor: Sun Q; Department of Chemistry, University of South Florida, 4202 E. Fowler Avenue, Tampa, FL, 33620, USA., Aguila B; Department of Chemistry, University of South Florida, 4202 E. Fowler Avenue, Tampa, FL, 33620, USA., Earl LD; Chemical Sciences Division, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN, 37831, USA., Abney CW; Chemical Sciences Division, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN, 37831, USA., Wojtas L; Department of Chemistry, University of South Florida, 4202 E. Fowler Avenue, Tampa, FL, 33620, USA., Thallapally PK; Physical and Computational Science Directorate, Pacific Northwest National Laboratory, Richland, WA, 99352, USA., Ma S; Department of Chemistry, University of South Florida, 4202 E. Fowler Avenue, Tampa, FL, 33620, USA.
Jazyk: angličtina
Zdroj: Advanced materials (Deerfield Beach, Fla.) [Adv Mater] 2018 May; Vol. 30 (20), pp. e1705479. Date of Electronic Publication: 2018 Mar 27.
DOI: 10.1002/adma.201705479
Abstrakt: The potential consequences of nuclear events and the complexity of nuclear waste management motivate the development of selective solid-phase sorbents to provide enhanced protection. Herein, it is shown that 2D covalent organic frameworks (COFs) with unique structures possess all the traits to be well suited as a platform for the deployment of highly efficient sorbents such that they exhibit remarkable performance, as demonstrated by uranium capture. The chelating groups laced on the open 1D channels exhibit exceptional accessibility, allowing significantly higher utilization efficiency. In addition, the 2D extended polygons packed closely in an eclipsed fashion bring chelating groups in adjacent layers parallel to each other, which may facilitate their cooperation, thereby leading to high affinity toward specific ions. As a result, the amidoxime-functionalized COFs far outperform their corresponding amorphous analogs in terms of adsorption capacities, kinetics, and affinities. Specifically, COF-TpAb-AO is able to reduce various uranium contaminated water samples from 1 ppm to less than 0.1 ppb within several minutes, well below the drinking water limit (30 ppb), as well as mine uranium from spiked seawater with an exceptionally high uptake capacity of 127 mg g -1 . These results delineate important synthetic advances toward the implementation of COFs in environmental remediation.
(© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
Databáze: MEDLINE
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