Physical and chemical properties of ionic liquids: novel materials for energy-related applications.
Our projects combine several aspects of modern chemistry that include several physical measurements, occasional chemical synthesis, computational and theoretical chemistry.
We use ultrafast time-resolved laser spectroscopy to initiate and probe photo-induced electron-transfer reactions in ionic liquids, to understand how the unique chemical and physical environment of these molten salts affect the outcomes of the simplest chemical reactions, and those that we must use to capture sunlight for renewable electrical and chemical energy supplies. We also apply several advanced NMR methods to measure the self-diffusion coefficient of the cations and anions comprising these liquids. This information is crucial for more efficient design of both next-generation batteries and ultra-capacitors, where the ionic liquids serve as the electrolytes. The other major research approach involves using x-rays from the national synchrotron light sources such as those at Argonne and Brookhaven National Labs. We do a variety of x-ray scattering, diffraction and spectroscopy experiments there, which provides information about the intermediate-range order present in many of the ionic liquids. Chemical synthesis is required either to generate a novel ionic liquid to test a new hypothesis, or to provide an ultra-pure sample for the laser spectroscopy experiments.
Significant Recent Publications or Reviews
E. W. Castner, Jr., C. J. Margulis, M. Maroncelli and J. F. Wishart, "Ionic Liquids: Structure and Photochemical Reactivity", Annual Reviews of Physical Chemistry, 62, 85-105 (2011).
E. W. Castner, Jr. and J. F. Wishart, "Spotlight on Ionic Liquids", J. Chem. Phys. 132, 120901 (2010).
E. W. Castner, Jr., J. F. Wishart and H. Shirota, "Intermolecular Dynamics, Interactions and Solvation in Ionic Liquids", Accounts of Chemical Research 2007, 40(11), 1217-1227.
The overriding qualification is a deep curiosity about atoms and molecules, and how we can use our skills in physics, mathematics and chemistry to investigate their properties and exploit them, especially for energy applications.
Commitment, persistence, stick-to-it-iveness, being a self-starter and willingness to lose oneself in laboratory work are the most important criteria; all are more significant than having a specific course background or GPA.
Suggested GPA range for new researchers: 2.5 to 4.0.
A key to our way of thinking about these liquids is to combine an approach based on quantum and statistical mechanics with chemical knowledge. Thus, students who adapt most rapidly to our labs usually have strong interests and abilities in physics, math, and physical chemistry, though knowledge of the principles of organic chemistry is also important for our work as well.
We have had a high-school student and first-year undergraduate students working in the lab, though it is much more common for students to begin research after they have taken the first several physics and math courses, and usually organic and physical chemistry.
Current Undergraduate Researchers
Jessalyn Devine, 3rd year, chem. chemical physics option
Patrick Kramer, 4th year, chem. majorchemical physics option
Eric Hagee, RU 2011, now Ph.D. student in Chemistry at U. Wisconsin, Madison
Steven Bagienski, RU 2010, Ph.D. student in Materials Sci. and Eng., Rutgers
Brenna Krieger, RU 2009, now NSF pre-doctoral fellow in Biophysics at Harvard
Publications with Undergraduate Co-authors (undergraduate author underlined)
B. M. Krieger, H. Y. Lee, T. J. Emge, J. F. Wishart and E. W. Castner, Jr., "Ionic Liquids and Solids with Paramagnetic Anions", Phys. Chem. Chem. Phys., 12, 8919-8925 (2010).
B. J. Lee, M. Barch, E. W. Castner, Jr., J. Völker and K. J. Breslauer, "Structure and Dynamics in DNA Looped Domains: CAG Triplet Repeat Sequence Dynamics Probed by 2-Aminopurine Fluorescence", Biochemistry, 2007, 46, 10756-10766.
S. H. Chung, R. Lopato, S. G. Greenbaum, H. Shirota, E. W. Castner, Jr., and J. F. Wishart, "A Nuclear Magnetic Resonance Study of the Dynamics of Imidazolium Ionic Liquids with -CH2Si(CH3)3 vs. -CH2C(CH3)3 substituents", J. Phys. Chem. B, 2007, 111(18), 4885-4893.
C. D. Grant, K. E. Steege, M. R. DeRitter, and E. W. Castner, Jr., "Microviscosity in Multiple Regions of Complex Aqueous Solutions of Poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)", Journal of Physical Chemistry B, 2005, 109(47), 22273-22284.
C. D. Grant, M. R. DeRitter, K. E. Steege, T. Fadeeva, and E. W. Castner, Jr., "Fluorescence probing of interior, interfacial, and exterior regions in solution aggregates of polyethylene oxide-polypropylene oxide-polyethylene oxide (PEO-PPO-PEO) triblock copolymers", Langmuir, 2005, 21 (5), 1745-1752.
Alfred B. Roney, Brian Space, E. W. Castner, R. L. Napoleon and P. B. Moore, "A Molecular Dynamics Study of Aggregation Phenomena in Aqueous n-Propanol", J. Phys. Chem. B 2004, 108, 7389-7401.
E. W. Castner, Jr., D. Kennedy, and R. J. Cave, "Solvent as Electron Donor: Donor/Acceptor Electronic Coupling Is a Dynamical Variable", Journal of Physical Chemistry A, 104(13), 2869-2885 (2000). (April 6, 2000 cover article).