A sustainable future: How materials science can make the planet cleaner

Clearing the way for cleaner energy

Something new at the pump

Biobutanol, first approved commercially in 2018 for gasoline blends, is one of the most promising alternative fuel sources available on the market today. Butanol, also known as butyl alcohol, is more closely related to gasoline than ethanol, and it contains significantly more energy per gallon - nearly as much as gasoline.

In 2020, chemistry professor Kyriakos Stylianou led a collaboration in the development of a new metal organic framework, or MOF, that may significantly increase the efficiency of producing biobutanol. Biobutanol production has been hampered by the need to separate the usable fuel from a fermentation ‘broth’ containing a maximum of about 2% butanol by weight. Previous separation methods have mostly relied on distillation, which is time-consuming and inefficient. The MOF that Stylianou’s team created, based on copper ions and carborane-carboxylate ligand, is able to separate butanol from the fermentation broth with greater efficiency than any other existing method. Stylianou is optimistic that with more efficient production methods and industry partnership, biobutanol can be a key player in the push to end fossil fuel dependency.

High-powered batteries, small carbon footprint

Chemist David Ji is revolutionizing energy storage potential and challenging long-held beliefs regarding what is possible in the field. Many of science’s most significant challenges stem from limitations in known available materials, but a 2020 discovery of “counter-ion insertion” has enabled the inclusion of many new solids not traditionally compatible with battery construction.

Most batteries store energy via cations - elements or molecules that hold a positive charge due to missing electrons. Energy can also be stored in anions, which have added negatively charged electrons. Ji’s research group was attempting research on this latter type when they inadvertently produced a far more exciting result. Rather than using either positively or negatively charged ions, their product had both involved in its electrochemical reduction-oxidation reaction, which they found greatly increased its storage capacity.

Their patent-pending battery chemistry holds remarkable potential to serve as a safer and more environmentally friendly energy storage alternative to current lithium-ion batteries used in cellphones, laptops, vehicles and more. Says Ji: “This is the beginning of a whole new field.”

Streamlining sustainable processes

Sustainable semiconductors

Silicon chips, necessary for tech ranging from phones to electric cars, require massive amounts of energy and water to produce. They also create hazardous waste. In the US, a single chip fabrication plant produced nearly 15,000 tons of waste over a three month period - and about 60% was hazardous. Humanity’s growing dependence on semiconductors, regardless of these statistics, sharply contrasts the goals outlined in the COP26 Climate Summit, and highlights the need for sustainable alternatives.

Renowned OSU materials scientist Janet Tate has helped lead the charge in the development of semiconductors to sustainably power today’s technology without jeopardizing outcomes for the future. Her research focuses on changes to the composition of the semiconductors themselves. In particular, she has specialized in the creation of semiconductors with transparent circuits which have optical properties enhancing the efficient conversion of solar energy. She has also investigated the largely unstudied area of heterostructural alloys - blends of compounds made from materials that don’t share the same atom arrangement. Since they have different structural components, the properties of these alloys can be more transient, providing greater opportunity to have control over the results.

Converting waste heat into energy

Waste heat is one of the leading contributors to greenhouse emissions - and also one of the least discussed. Estimates suggest that some 63% of global primary energy - the energy directly embodied in natural resources - is lost during combustion and the heat transfer process. To address this problem, physicist Matt Graham has begun a new project to develop a prototype of an ultralow bandgap semiconductor device to convert residual waste heat to energy.

His research group, which he has termed the Micro-Femto Energetics Lab, investigates how electrons in new nanoscale devices and materials can be harvested for energy, solar and electronics applications. The lab employs a variety of physical tools ‘to film’ how electrons behave on a nanoscale interface with the goal of better understanding and eliminating bottlenecks that cause inefficiencies in solar materials.

Reducing pollution

Reducing planet-warming CO2 in the atmosphere

Once introduced to the atmosphere, CO2 will linger on well beyond the human lifespan, from 300 to 1,000 years. With so much at stake, developing technology to reduce the CO2 levels in the atmosphere is crucial. These studies are particularly important at a time when projections for climate change due to CO2 and other greenhouse gasses are increasingly alarming. According to an October 2019 report from NASA, carbon dioxide in the atmosphere has increased 48% since the beginning of the industrial age, with one quarter of the increase taking place in the past 20 years.

In 2019, Stylianou discovered a way to scrub carbon directly from smokestacks using metal organic frameworks with the ability to intercept CO2 molecules from flue gas. Sifting through more than 325,000 MOFs in a digital library, his team identified different types of CO₂ binding sites that would maintain their selectivity in the presence of water. Among the MOFs screened, they identified two that met the criteria. Lab tests showed that the MOFs performed better than CO2 removal materials currently available on the market at a much lower price point.

Last year, fellow inorganic chemist May Nyman was selected as one of the leaders of a $24 million federal effort to develop technologies for combating climate change by extracting carbon from the air. The funding is spread among nine research projects, with Nyman receiving $1.6 million over three years to lead a collaboration that includes scientists from the Argonne National Laboratory as well as Oregon State.

Alice Lulich, an Honors senior in chemistry, started working with Nyman her first year of college, receiving funding through the Summer Undergraduate Research (SURE) Science program. During the program, Lulich “made one of the greatest discoveries in my lab through her synthesis experiments,” said Nyman. “Alice identified a molecule directly that is responsible for energy production from sunlight, that previously has only been implied,” said Nyman. “She made this discovery by trapping the molecule in a material so that it could be analyzed by single crystal x-ray diffraction.”

Nuclear waste clean-up

Nuclear stockpile safety is of critical national importance: How can we ensure that aging nuclear weapons and legacy nuclear waste sites are safely maintained, recycled or disposed of?

To address that need, Nyman is part of a five-year, $12.5 million National Nuclear Security Administration (NNSA) grant for an Actinide Center of Excellence (ACE) to conduct research in actinide and nuclear chemistry important for Stockpile Stewardship, the certification that the nation’s nuclear weapons are secure and operational. The goal of the research is to determine how actinide nuclear material ages, how it travels in the environment in the case of contamination, and how it can be recycled and repurposed (i.e. for nuclear energy). Actinides are all radioactive and include uranium, thorium, and plutonium, elements most commonly used in nuclear reactors and weapons.

In part two of this series, we will examine how faculty are taking action to address the effects of climate change and ecological degradation on living organisms, as well as engaging biological tools for harm reduction.