Doctoral candidate researches gas system sensing in high temperatures and harsh environments

Julia WittkamperAs a participant in the Mickey Leland Energy Fellowship program, Julia Wittkamper used pulsed laser deposition technology to create gas sensors which can withstand temperatures reaching 900 C (165 F). The MLEF Program is administered by ORAU through its contract with the U.S. Department of Energy to manage the Oak Ridge Institute for Science and Education. (Photo courtesy of Virginia Jimenez, MLEF)

Reducing the environmental impact of fossil-fuel based power generation could hinge on increasing the capability of today’s sensors to withstand higher temperature and a harsher environment. That’s the mission Julia Wittkamper, a doctoral candidate in material science and engineering at Carnegie Mellon University, undertook during her summer fellowship at the U.S. Department of Energy’s (DOE) National Energy Technology Laboratory (NETL).

Wittkamper received this challenge as part of her Mickey Leland Energy Fellowship (MLEF), a 10-week program that expands STEM opportunities for women and minority students. This program is administered by ORAU through its contract with the DOE to manage the Oak Ridge Institute for Science and Education.

“Optical gas sensing is used to detect different gas concentrations by measuring gas properties such as transmission, reflection and luminescence,” said Wittkamper. “Currently, most gas sensors are not able to sustain a wide range of temperatures, especially those reaching 900 degrees Celsius, which typically exist in many fossil-fuel based generation systems.”

Using technology known as pulsed laser deposition (PLD), Wittkamper was able to vaporize strontium titanate and then deposit it as a thin layer on a film. These films were then added to quartz-based surfaces in an attempt to create hardier gas sensors.

“If effective, these films could create gas sensors that can work well in a variety of hard environments, such as many of today’s fossil-fuel based plants,” she said. “These sensors would allow real-time monitoring of what’s going on within these plants, which, in turn, could improve the way the plant is operated. This could increase both the plant’s efficiency and reduce its emissions.”

This technology could also improve the safety for researchers who work in these harsh environments, Wittkamper added.

In addition to fossil-fuel systems, these sturdier gas sensors also could be used to monitor and understand the reactions inside fuel cells used in today’s electric vehicles. With this knowledge, researchers can then attempt to increase the efficiency of the cells and possibly improve future technology for electric vehicles.

Daily activities for Wittkamper included creating her films using PLD technology and then characterizing the films using various equipment that included scanning electron microscopes, x-ray diffraction or spectroscopy. Once the film was characterized, it could be incorporated into a gas sensor and tested using NETL technology.

“The great thing about this research project was that I used several of the same characterization techniques I had used in previous research, but I discovered different uses and gained a deeper understanding for them,” Wittkamper said, “The MLEF program gave me experience in research that is different but related to my graduate research and provided me with insight into possible post-graduation career paths I could pursue.”

Wittkamper’s advice to future MLEF participants is to network and maintain connections with everyone they may work with, including other fellows. She advises others to apply for the program because it will help them to understand how federal laboratories operate, and serve as a way to gain research experience in a new area.

After completion of her doctoral program, Wittkamper would like to obtain a research and development position in either the industry or government.