Engineering More Sustainable Materials for the Future

Duke Engineering launched the Beyond the Horizon initiative to provide interdisciplinary teams with substantial investment to begin pursuing extremely high-risk, high-reward projects that have the potential for deep, transformative societal impact. In 2024-2025, three proposals were selected for an initial round of funding that will play key roles in shaping Duke Engineering’s future research and teaching profile. Each play to the school’s unique strengths and holds the promise of helping to define the future of their respective fields.

To address one of the largest issues facing the future of humanity – climate change – you inherently must think big. At the same time, it’s also important to think small.

A project supported by Duke Engineering’s Beyond the Horizon initiative looks at all aspects of scale, from the molecular to the macro, in developing sustainable materials of the future.

Heileen “Helen” Hsu-Kim, professor of civil and environmental engineering (CEE), is leading a super team of engineers and scientists who want to build a greener future. Leveraging their expertise and existing collaborations from the Duke Materials Initiative (DMI), the team also hopes to establish Duke as a hub for sustainable material research and education.

“This collaboration is about tackling multiple complex, big challenges in the overarching framework of sustainable materials,” Hsu-Kim said. “There’s a lot of ongoing efforts in materials development at Duke, but there’s a gap in sustainable materials that we can fill.”

The project is split into three separate themed areas that target specific material use applications: infrastructure materials, energy materials and materials for resource health.

Infrastructure Materials

Concrete production creates about eight percent of human-caused global CO₂ emissions, according to a report from the Royal Institute of International Affairs.

Hsu-Kim, along with Laura Dalton, assistant professor of CEE, and Michaela Geri, assistant professor of mechanical engineering and materials science (MEMS) will explore the feasibility of incorporating legacy coal ash waste into alternative cement-based composites.

These new formulations would leverage coal ash wastes harvested from landfills, for which there are hundreds across the United States collectively holding more than 2 billion tons of coal ash and leaching toxins to groundwater. The team aims to develop new cement composites that can enhance carbon capture while maintaining similar properties in strength and durability relative to traditional cements.

“As an environmental geochemist, I’m interested in mitigating the exposure of harmful pollutants like coal ash waste to humans, and it’s exciting to work toward encapsulating and incorporating that waste within the concrete production process,” Hsu-Kim said.

Energy Materials

This team, led by Veveakis and Volker Blum, the Rooney Family Associate Professor of MEMS, aims to accelerate the performance of materials for decarbonized energy systems, such as storage for hydrogen, CO₂ and thermal fluids. They will run simulations at different scales and properties to optimize the efficacy of materials to retain gases such as hydrogen and CO₂.

“By combining basic physics, material science and engineering, we are aiming at designing efficient energy storage materials that do not rely on critical minerals,” Veveakis said.

Materials for Resource Health

The third theme concerns preserving the health of and building resilience in natural resources like water, soil and air.

A team led by Leanne Gilbertson, associate professor of CEE ; Hossein “Amir” Salahshoor, assistant professor of CEE ; Shyni Varghese, the Laszlo Ormandy Distinguished Professor of Orthopaedic Surgery and a professor of biomedical engineering and MEMS; and Stefan Zauscher, professor of MEMS and co-director of DMI, proposes to develop stimuli-responsive materials that can adapt to changing environmental conditions and target delivery in microenvironments.

Their first imagined application is agriculture soils. Crop production requires inputs of large quantities of fertilizer, pesticides and other chemicals, many of which do not reach the intended crop, leading to runoff and leaching into the environment.

Responsive materials keep the chemical locked away until a condition, which aligns with plant needs, triggers a release reaction. Relevant triggers are moisture, temperature and pH level. Optimizing the delivery of agrochemicals supports more resource-efficient crop growth, improving the health of the surrounding environment.

“The interdisciplinary expertise of our team allows us to consider many diverse perspectives early on in the design process of environmentally responsive materials,” Gilbertson said. “With both computational modeling and empirical approaches, we can see ways to improve the design of our materials and new applications. Personally, the project is enriching my knowledge in the power of computational material design in exciting ways.”

Through their first year of funding, Hsu-Kim hopes to demonstrate proof of concept of their design approach with concrete data (no pun intended) to support a new combined computational and experimental approach toward sustainably designed materials for large-scale applications.

Although these three teams haven’t worked together before, Hsu-Kim is grateful for the forward-thinking vision of the Beyond the Horizon grant that enables it.

“Since we’re not a huge university, it’s easier to cross disciplinary boundaries, and we have the opportunity to take on the most interesting research problems like sustainable materials,” Hsu-Kim said.