Texas Tech Researcher’s Partnership with Chemists in Northern Ireland, Italy Finds
Ionic Liquid’s Makeup Measurably Non-Uniform at the Nanoscale
November 10, 2009
Researchers find that parts of ionic liquids at the nanoscopic level were not uniform.
Researchers at Texas Tech University, Queen’s University Belfast, Northern Ireland,
the University of Rome and the National Research Council in Italy recently made a
discovery about the non-uniform chemical compositions of ionic liquids that could
lead to greater understanding and manipulation of these multi-purpose, designer solvents.
Their findings were published online in the Journal of Physics: Condensed Matter.
The article was selected for inclusion in the Institute of Physics’ IOP Select
, which is a special collection of articles chosen by IOP editors based on research
showing significant breakthroughs or advancements, high degree of novelty and significant
impact on future research.
Ionic liquids are a new frontier of research for chemists. Originally invented to
replace volatile and toxic solvents such as benzene, they’re now used in high-efficiency
solar cells, as cheaper, more environmentally friendly rocket fuel additives and to
more effectively dissolve plant materials into biofuels. Since 1990, research on ionic
liquids has grown exponentially.
“Their properties are strikingly different than those of most conventional liquids,”
said Edward Quitevis, a professor of chemistry in the Texas Tech Department of Chemistry
and Biochemistry. “A conventional liquid for the most part is composed of neutral
molecules whereas an ionic liquid is composed entirely of ions.”
Because of their ability to be tailored and manipulated for specific applications,
ionic liquids can be compared to a new form of Erector Set for chemists. By modifying
the ions, scientists can create specific properties in the liquids to fit particular
applications or discover new materials.
Each new discovery that adds to the understanding of ionic liquids leads to new possibilities
for applications and materials, Quitevis said.
“An ionic liquid is basically a salt that happens to have a melting point at or about
room temperature,” he said. “The reason why it’s a liquid and not a solid is because
the ions are bulky and don’t crystallize readily. The more we learn about them, the
more we can find new applications for them that we never could have imagined for conventional
By using X-rays and lasers, researchers found that parts of the liquid at the nanoscopic
level were not uniform. Some domains of the liquid may have had more or less density
or viscosity compared to other domains. Also, these non-uniform domains could be measured.
“At the nanoscopic scale, these liquids are not uniform, compared to other liquids,
such as water, where properties are all uniform throughout,” Quitevis said. “This
non-uniformity is not random. These domains of non-uniformity are well defined and
can be measured. And this nanoscopic non-uniformity was predicted in computer simulations,
but never confirmed experimentally until recently.”
Understanding these types of attributes of ionic liquids can lead to more breakthroughs
in the future, Quitevis said.
Quitevis’s work was funded by the National Science Foundation and the American Chemical
Society Petroleum Research Fund.
For a copy of the study, visit the IOP Web site
CONTACT: Edward Quitevis, professor of chemistry, Department of Chemistry and Biochemistry,
Texas Tech University,
(806) 742-3066, or email@example.com