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Title: Controlling the intermediate structure of an ionic liquid for f-block element separations

Abstract

Recent research has revealed molecular structure beyond the inner coordination sphere is essential in defining the performance of separations processes, but nevertheless remains largely unexplored. Here we apply small angle neutron scattering (SANS) and x-ray absorption fine structure (XAFS) spectroscopy to investigate the structure of an ionic liquid system studied for f-block element separations. SANS data reveal dramatic changes in the ionic liquid microstructure (~150 Å) which we demonstrate can be controlled by judicious selection of counter ion. Mesoscale structural features (> 500 Å) are also observed as a function of metal concentration. XAFS analysis supports formation of extended aggregate structures, similar to those observed in traditional solvent extraction processes, and suggest additional parallels may be drawn from further study. As a result, achieving precise tunability over the intermediate features is an important development in controlling mesoscale structure and realizing advanced new forms of soft matter.

Authors:
ORCiD logo [1];  [1];  [1];  [2];  [1]; ORCiD logo [3]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  2. Argonne National Lab. (ANL), Lemont, IL (United States); Illinois Inst. of Technology, Chicago, IL (United States)
  3. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Univ. of Tennessee, Knoxville, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Spallation Neutron Source (SNS)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1364322
Grant/Contract Number:
AC05-00OR22725
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Physical Chemistry Letters
Additional Journal Information:
Journal Volume: 8; Journal Issue: 9; Journal ID: ISSN 1948-7185
Publisher:
American Chemical Society
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY

Citation Formats

Abney, Carter W., Do, Changwoo, Luo, Huimin, Wright, Joshua, He, Lilin, and Dai, Sheng. Controlling the intermediate structure of an ionic liquid for f-block element separations. United States: N. p., 2017. Web. doi:10.1021/acs.jpclett.7b00755.
Abney, Carter W., Do, Changwoo, Luo, Huimin, Wright, Joshua, He, Lilin, & Dai, Sheng. Controlling the intermediate structure of an ionic liquid for f-block element separations. United States. doi:10.1021/acs.jpclett.7b00755.
Abney, Carter W., Do, Changwoo, Luo, Huimin, Wright, Joshua, He, Lilin, and Dai, Sheng. Wed . "Controlling the intermediate structure of an ionic liquid for f-block element separations". United States. doi:10.1021/acs.jpclett.7b00755. https://www.osti.gov/servlets/purl/1364322.
@article{osti_1364322,
title = {Controlling the intermediate structure of an ionic liquid for f-block element separations},
author = {Abney, Carter W. and Do, Changwoo and Luo, Huimin and Wright, Joshua and He, Lilin and Dai, Sheng},
abstractNote = {Recent research has revealed molecular structure beyond the inner coordination sphere is essential in defining the performance of separations processes, but nevertheless remains largely unexplored. Here we apply small angle neutron scattering (SANS) and x-ray absorption fine structure (XAFS) spectroscopy to investigate the structure of an ionic liquid system studied for f-block element separations. SANS data reveal dramatic changes in the ionic liquid microstructure (~150 Å) which we demonstrate can be controlled by judicious selection of counter ion. Mesoscale structural features (> 500 Å) are also observed as a function of metal concentration. XAFS analysis supports formation of extended aggregate structures, similar to those observed in traditional solvent extraction processes, and suggest additional parallels may be drawn from further study. As a result, achieving precise tunability over the intermediate features is an important development in controlling mesoscale structure and realizing advanced new forms of soft matter.},
doi = {10.1021/acs.jpclett.7b00755},
journal = {Journal of Physical Chemistry Letters},
number = 9,
volume = 8,
place = {United States},
year = {Wed Apr 19 00:00:00 EDT 2017},
month = {Wed Apr 19 00:00:00 EDT 2017}
}

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