David Sholl: Driving decarbonized energy system

David Sholl has come to the U.S. Department of Energy's Oak Ridge National Laboratory with a wealth of scientific expertise and a personal mission: hasten the development and deployment of decarbonization solutions for the nation's energy system.

Sholl, director of the lab's new Transformational Decarbonization Initiative, is working to elevate ORNL's prominence in decarbonization science and technology including carbon capture, conversion and utilization, and storage.

"Decarbonization is a very important area of national need," Sholl said. "It's also an area where things need to happen rapidly and at large scale. That's something ORNL is well positioned to do: to think about things at multiple scales at the same time, and to work across government and industry to really change the way things are done in the future.

"Transitioning to a decarbonized economy represents a massive societal challenge," Sholl said. "There are some things that are already happening and are driven by economic forces. But there are some areas of the economy that are very difficult to decarbonize. That's where the lab can have a significant influence in developing new technologies including in the chemical process industry and for production of cement and steel. These are large-volume processes that are very important to the economy and that we just don't have ways to do without emitting carbon at the moment."

More specifically, the initiative will encompass fundamental science and scale-up technologies for direct air capture, point source capture, innovative materials and processes, bio-inspired approaches and natural sinks, combining electrochemical, thermomechanical, photochemical processes and other solutions for cost-effective decarbonization at a national scale.

"I am excited to add David to the ESTD team," said Xin Sun, ORNL's associate laboratory director for energy science and technology. "Decarbonization is a top priority for us, so hiring someone of David's caliber is a significant step. I am confident he will lead effective and innovative collaborations across the lab and help drive our nation's efforts to decarbonize in the face of global climate change."

Department of Energy Principal Deputy Assistant Secretary for Fossil Energy and Carbon Management Dr. Jennifer Wilcox said she also supports the mission of Sholl and TDI.

"I am pleased to see David take on a key role in addressing the critical challenge of decarbonization," Wilcox said. "David is known for taking innovative approaches to addressing major questions like this, so I look forward to seeing the solutions that will come out of the Transformational Decarbonization Initiative under his leadership."

Advancing decarbonization with world-class capabilities

Sholl said he is looking forward to meeting people from many areas at ORNL. "Decarbonization technologies will need to draw on expertise from across the laboratory. Learning about the many skills that already exist here and helping connect them in potentially new ways is an exciting prospect," he added.

ORNL has a rich history in decarbonization breakthroughs, including the invention of a new method and materials for the conversion of CO₂ to ethanol, a practical, energy-efficient method of capturing CO₂ directly from air, as well as the invention of a new low-cost, 3D-printed device that improves point source carbon capture.

ORNL's researchers are using the lab's world-class capabilities and expertise in nanoscience, neutron science, high-performance computing, combustion and propulsion science, chemistry and materials science, geoscience, electrical engineering, manufacturing, buildings science and more to guide technological solutions from carbon capture to storage and utilization.

The lab is also advancing solutions for green hydrogen production and end-use. A project is underway to develop low-cost electrolyzers for green hydrogen production, using renewable electricity to break water into oxygen and hydrogen through electrolysis. The cost savings potential is significant. Electricity currently accounts for some 80% of the cost of producing green hydrogen via electrolysis.

To address storage and distribution issues, scientists are creating high-strength, low-cost carbon fiber for lightweight storage of hydrogen at DOE's Carbon Fiber Technology Facility at ORNL. The lab is also developing new materials for hydrogen fuel cells, using the atomic-level characterization facilities at the DOE Center For Nanophase Materials Sciences. Scientists likewise continue to enhance ORNL's CO₂ direct-air capture technology, with plans to create a process that mixes captured CO₂ with hydrogen to create a net-zero-carbon liquid fuel for heavy-duty applications such as ships and locomotives, utilizing capabilities at the DOE National Transportation Research Center.

Deployment-focused research

Sholl's personal career has focused on using materials modeling to develop new chemical process technologies, blending academic research and industry collaboration to develop solutions and to make sure they are deployed. He comes to ORNL from the Georgia Institute of Technology, where he was the John F. Brock III School Chair in the School of Chemical and Biomolecular Engineering for the past eight years. Prior to that, he was on the faculty at Carnegie Mellon University for 10 years and held postdoctoral appointments at Pennsylvania State and Yale University.

Sholl grew up in Australia, where his first introduction to the world of science came early - his father was a college physics professor. Sholl ended up majoring in theoretical physics himself as an undergrad at Australian National University. He even wrote a paper with his dad, focused on the diffusion of hydrogen with metals. "It was a pretty interesting experience, and the modeling that went into it is still applicable in my work today," he said.

He spent a year during his undergrad days as an exchange student in San Diego, where he met a fellow student who would later become his wife. Sholl pursued his graduate studies in the states, earning his master's and doctoral degrees in applied mathematics at the University of Colorado at Boulder.

While rooted in academia during much of his career, Sholl has direct experience with DOE's national laboratory complex and its capabilities. He collaborated with ORNL researchers as part of the Center for Understanding and Control of Acid Gas-Induced Evolution of Materials for Energy, a DOE Energy Frontier Research Center at Georgia Tech. In his time at Carnegie Mellon, Sholl worked with the National Energy Technology Laboratory on chemical separations and methods to capture carbon dioxide from coal-fired plants.

Making a difference for a healthier planet

"That carbon capture work and the importance of reducing the vast amount of energy required for chemical separations - those two things together highlighted the importance of decarbonization for me and encouraged me to continue my research," he said. "I love solving scientific puzzles and find it very satisfying to work on solutions that will really make a positive difference in the world."

His research has focused more specifically on computational materials modeling and the development of porous materials for carbon capture applications, membranes for gas separations and heterogeneous catalysis. One of his favorite projects has been his long collaboration with ExxonMobil on modeling and simulation to predict the properties of new materials.

"With the computational math we developed in the project, we went from simply explaining what happened in an experiment to the point where our simulations now make predictions that do not have to be exhaustively verified through experiments," he said.

Sholl is recognized as a leader in his field, as a fellow of the American Institute of Chemical Engineers, or AIChE, a current member of the AIChE Board of Directors and a fellow of the American Association for the Advancement of Science. He was a senior editor for Langmuir for 10 years and has published more than 370 papers and three books. His most recent book, "Success and Creativity in Scientific Research," offers career advice to young scientists based on a popular lecture series at Georgia Tech.

Sholl reiterated that he's looking forward to getting to know ORNL colleagues across the spectrum from basic to applied science. "I've always enjoyed building community in my research. It's connections between people that get things done."