New electron spectrometer allows chemistry researchers a closer look at materials

Researchers with the Virginia Tech Department of Chemistry have a new, high-tech tool on their hands that can help them and others take a closer look than ever before at materials produced at Virginia Tech and beyond.

Part of the Virginia Tech College of Science, the department recently took delivery of a VersaProbe III X-ray Photoelectron Spectroscopy (XPS) instrument manufactured by Physical Electronics Inc. The machine resembles R2-D2 from “Star Wars,” with his curved top off to one side and large tubes crossing in various directions. It allows researchers to look at slivers of sample materials on an elemental level.

Amanda Morris, an assistant professor of chemistry, said the machine allows a user to look on a microscale level at the thin surface layer of nearly any material. In essence, this makes it possible for researchers to look at the top layer of paint on a car as part of thin-film analyses.  

“This surface sensitive technique allows you to look at tiny molecules as they’re doing their job,” said Morris. “From polymeric and metallic coatings to battery materials and photovoltaics, this tool expands the university’s surface analysis capabilities to specialized materials and experimental conditions.”

Morris led a National Science Foundation grant application for the $775,000 machine. The request was filed in January 2015, with Morris hearing in fall 2015 that Virginia Tech would receive the VersaProbe device, only the second university in the United States to do so. Assisting with the application were John Morris, professor of chemistry, and Lou Madsen, associate professor of chemistry, and Kathy Lu, professor of materials science and engineering in the Virginia Tech College of Engineering.

“Our XPS facilities enable state-of-the-art, specialized measurements,” added Amanda Morris. “Couple this to the fact that the surface analysis laboratory also has surface sensitive vibrational spectroscopy and an atomic force microscope, and we truly have the unique ability to service the university and beyond.”

Among other features: An argon sputter ion gun for submicron surface analysis, and the ability to capture and view data in real time. Materials tested by the machine could be cooled to a low temperature of minus 140 degrees Fahrenheit and heated to a maximum temperature of 600 degrees Fahrenheit. The sample stage also has the ability to apply an electrochemical potential across the sample in situ. Additionally, the instrument can be interfaced with two sample transfer chambers to ensure oxygen-free transfer of materials to be explored. Sample sizes inserted into the machine would be no larger than a penny.

Amanda Morris said she would use the machine for her work on metal-organic framework thin film arrays and next-generation solar cells, being able to see how the surfaces change when exposed to light.

She added that researchers from across Virginia Tech would be able to use the machine to test materials. Further, the department invites external submissions from private-sector businesses and government agencies. “We welcome partnerships with government, industry, and other academic institutions,” said Amanda Morris. “We will have a full time technician to run and analyze samples.”

Madsen said he and his team of graduate and undergraduate students plan to further test prototype ionic gels that could be used in safer, but powerful batteries, fuel cells, artificial muscles, and supercapacitors. “All of these technologies require carefully tailored interactions among many different atoms, and XPS can gather information about these interactions,” added Madsen.