To prevent the atmospheric release of waste carbon dioxide, researchers seek to improve methods to capture and store the compound. A faculty and student team from Lawrence University joined the global effort in the Visiting Faculty Program (VFP) at Oak Ridge National Laboratory (ORNL).

For 10 weeks over the summer, Allison Fleshman, Ph.D., and Nicolette Puskar collaborated with ORNL’s Shannon Mahurin, Ph.D., to better understand the diffusive properties of ammonium-based ionic liquids. According to Fleshman, “These ionic liquids show great promise for carbon dioxide capture as a gas separation medium.”

VFP Profile: Allison Fleshman and Nicolette Puskar
Allison Fleshman, Ph.D. and Nicolette Puskar, a faculty and student team from Lawrence University, contributed to chemistry and materials science research in the Visiting Faculty Program at Oak Ridge National Laboratory.

Using fluorescence correlation spectroscopy techniques, they were able to track single molecules through ionic liquids and measure the diffusion coefficients of the molecules. By obtaining a clear understanding of the material’s properties before carbon dioxide was added, the group developed a benchmark for comparison.

“We could actually see the molecules fluorescing in the microscope,” Puskar said. “It looked like a glittering liquid, and it was amazing and insane and beautiful to see a fluorescing molecule with my own eyes.”

Fleshman is a chemistry professor and a former visiting researcher at ORNL. The VFP program allowed her to introduce her student, Puskar, to chemistry at ORNL. Puskar was excited when this opportunity arose because she considers spectroscopy and sustainability  potential career paths.

Both Fleshman and Puskar enjoyed being surrounded by research peers and colleagues each day. The collaborative nature of the project proved beneficial for all involved. In fact, Fleshman brought a piece of equipment from her home university and collected data on novel ionic liquids synthesized by Mahurin and his group.

“I work at a small liberal arts college, and while my colleagues are brilliant in their respective fields, our fields don’t overlap often,” Fleshman said. “It is difficult to stay engaged in research when you are an island. ORNL is the oasis of research for a faculty member from a smaller research setting.”

Fleshman plans to incorporate her new skills and knowledge into her teaching and research at Lawrence University, located in Appleton,Wisconsin.

After the program, the duo returned to Lawrence University. Fleshman hopes to maintain collaborative relationships with ORNL, while Puskar plans to complete her undergraduate degrees in chemistry and vocal performance.

“This experience will benefit my research, my students and the university. Also, the networking with researchers at ORNL is invaluable,” Fleshman said. “I’ve met so many new and interesting people and will maintain many of these new contacts.”


The team looks forward to the future of science in their fields and the potential capabilities of carbon capture. Puskar said, “Our project was right on the cusp of physical chemistry and materials science, so envisioning the long-term goals of this project and its future collaborations in relation to carbon capture is inspiring.”

This research was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division.

The VFP program is sponsored by the U.S. Department of Energy Office of Science’s Office of Workforce Development for Teachers and Scientists (WDTS) and is administered by the Oak Ridge Institute for Science and Education (ORISE), managed by ORAU.