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    Soaring high, in the Army and the lab

    Starting off as a junior helicopter pilot, Lt. Col. Jill Rahon deployed to Afghanistan three times. During the last one, she was an air mission commander, the  pilot who is designated to interface with the ground troops throughout the mission.

    Today, Rahon is a fourth-year doctoral student studying applied physics at the Department of Nuclear Science and Engineering (NSE). Under the supervision of Areg Danagoulian, she is working on engineering solutions for enforcement of nuclear nonproliferation treaties. Rahon and her husband have 2-year-old twins: “They have the same warm relationship with my advisor that I had with my dad’s (PhD) advisor,” she says.

    Jill Rahon: Engineering solutions for enforcement of nuclear nonproliferation treaties

    A path to the armed forces

    The daughter of a health physicist father and a food chemist mother, Rahon grew up in the Hudson Valley, very close to New York City. Nine-eleven was a life-altering event: “Many of my friends’ fathers and uncles were policemen and firefighters [who] died responding to the attacks,” Rahon says. A hurt and angry teenager, Rahon was determined to do her part to help: She joined the Army and decided to pursue science, becoming part of the first class to enter West Point after 9/11.

    Rahon started by studying strategic history, a field that covers treaties and geopolitical relationships. It would prove useful later. Inspired by her father, who works in the nuclear field, Rahon added on a nuclear science and engineering track.

    After graduating from West Point, Rahon wanted to join active combat and chose aviation. At flight school in Fort Novosel, Alabama, she discovered that she loved flying. It was there that Rahon learned to fly the legendary Chinook helicopter. In short order, Rahon was assigned to the 101st Airborne Division and deployed to Afghanistan quickly thereafter.

    As expected, flying in Afghanistan, especially on night missions, was adrenaline-charged. “You’re thinking on the fly, you’re talking on five different radios, you’re making decisions for all the helicopters that are part of the mission,” Rahon remembers. Very often Rahon and her cohorts did not have the luxury of time. “We would get information that would need to be acted on quickly,” she says. During the planning meetings, she would be delighted to see a classmate from West Point function as the ground forces commander. “It would be surprising to see somebody you knew from a different setting halfway around the world, working toward common goals,” Rahon says.

    Also awesome: helping launch the first training program for female pilots to be recruited in the Afghan National Air Force. “I got to meet [and mentor] these strong young women who maybe didn’t have the same encouragement that I had growing up and they were out there hanging tough,” Rahon says.

    Exploring physics and nuclear engineering

    After serving in the combat forces, Rahon decided she wanted to teach physics at West Point. She applied to become a part of the Functional Area (FA52) as a nuclear and countering weapons of mass destruction officer.

    FA52 officers provide nuclear technical advice to maneuver commanders about nuclear weapons, effects, and operating in a nuclear environment or battlefield. Rahon’s specialty is radiation detection and operations in a nuclear environment, which poses unique threats and challenges to forces.

    Knowing she wanted to teach at West Point, she “brushed up extensively on math and physics” and applied to MIT NSE to pursue a master’s degree. “My fellow students were such an inspiration. They might not have had the same life experiences that I had but were still so mature and driven and knowledgeable not only about nuclear engineering but how that fits in the energy sector and in politics,” Rahon says.

    Resonance analysis to verify treaties

    Rahon returned to NSE to pursue her doctorate, where she does a “lot of detection and treaty verification work.”

    When looking at nuclear fuels to verify safeguards for treaties, experts search for the presence and quantities of heavy elements such as uranium, plutonium, thorium, and any of their decay products. To do so nondestructively is of high importance so they don’t destroy a piece of the material or fuel to identify it.

    Rahon’s research is built on resonance analysis, the fact that most midrange to heavy isotopes have unique resonance signatures that are accessed by neutrons of epithermal energy, which is relatively low on the scale of possible neutron energies. This means they travel slowly — crossing a distance of 2 meters in tens of microseconds, permitting their detection time to be used to calculate their energy.

    Studying how neutrons of a particular energy interact with a sample to identify worrisome nuclear materials is much like studying fingerprints to solve crimes. Isotopes that have a spike in likelihood of interaction occurring over a small neutron energy are said to have resonances, and these resonance patterns are isotopically unique. Experts can use this technique to nondestructively assess an item, identifying the constituent isotopes and their concentrations.

    Resonance analysis can be used to verify that the fuels are what the nuclear plant owner says they are. “There are a lot of safeguards activities and verification protocols that are managed by the International Atomic Energy Agency (IAEA) to ensure that a state is not misusing nuclear power for ulterior motives,” Rahon points out. And her method helps.

    “Our technique that leverages resonance analysis is nothing new,” Rahon says, “It’s been applied practically since the ’70s at very large beam facilities, hundreds of meters long with a very large accelerator that pulses neutrons, and then you’re able to correlate a neutron time of flight with a resonance profile. What we’ve done that is novel is we’ve shrunk it down to a 3-meter system with a portable neutron residence generator and a 2-meter beam path,” she says.

    Mobility confers many significant advantages: “This is something that could be conceivably put on the back of a truck and moved to a fuel facility, then driven to the next one for inspections or put at a treaty verification site. It could be taken out to a silo field where they are dismantling nuclear weapons,” Rahon says. However, the miniaturization does come with significant challenges, such as the neutron generator’s impacts on the signal to noise ratio.

    Rahon is delighted her research can ensure that a necessary fuel source will not be misused. “We need nuclear power. We need low-carbon solutions for energy and we need safe ones. We need to ensure that this powerful technology is not being misused. And that’s why these engineering solutions are needed for these safeguards,” she says.

    Rahon sees parallels between her time in active duty and her doctoral research. Teamwork and communication are key in both, she says. Her dad is her role model and Rahon is a firm believer in mentorship, something she nurtured both in the armed forces and at MIT. “My advisor is genuinely a wonderful person who has always given me so much support from not only being a student, but also being a parent,” Rahon adds.

    In turn, Danagoulian has been impressed by Rahon’s remarkable abilities: “Raising twins, doing research in applied nuclear physics, and flying coalition forces into Taliban territory while evading ground fire … [Jill] developed her own research project with minimal help from me and defended it brilliantly during the first part of the exam,” he says. 

    It seems that Rahon flies high no matter which mission she takes on. More

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    Making nuclear energy facilities easier to build and transport

    For the United States to meet its net zero goals, nuclear energy needs to be on the smorgasbord of options. The problem: Its production still suffers from a lack of scale. To increase access rapidly, we need to stand up reactors quickly, says Isabel Naranjo De Candido, a third-year doctoral student advised by Professor Koroush Shirvan.

    One option is to work with microreactors, transportable units that can be wheeled to areas that need clean electricity. Naranjo De Candido’s master’s thesis at MIT, supervised by Professor Jacopo Buongiorno, focused on such reactors.

    Another way to improve access to nuclear energy is to develop reactors that are modular so their component units can be manufactured quickly while still maintaining quality. “The idea is that you apply the industrialization techniques of manufacturing so companies produce more [nuclear] vessels, with a more predictable supply chain,” she says. The assumption is that working with standardized recipes to manufacture just a few designed components over and over again improves speed and reliability and decreases cost.

    As part of her doctoral studies, Naranjo De Candido is working on optimizing the operations and management of these small, modular reactors so they can be efficient in all stages of their lifecycle: building; operations and maintenance; and decommissioning. The motivation for her research is simple: “We need nuclear for climate change because we need a reliable and stable source of energy to fight climate change,” she says.

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    A childhood in Italy

    Despite her passion for nuclear energy and engineering today, Naranjo De Candido was unsure what she wanted to pursue after high school in Padua, Italy. The daughter of a physician Italian mother and an architect Spanish father, she enrolled in a science-based high school shortly after middle school, as she knew that was the track she enjoyed best.

    Having earned very high marks in school, she won a full scholarship to study in Pisa, at the special Sant’Anna School of Advanced Studies. Housed in a centuries-old convent, the school granted only masters and doctoral degrees. “I had to select what to study but I was unsure. I knew I was interested in engineering,” she recalls, “so I selected mechanical engineering because it’s more generic.”

    It turns out Sant’Anna was a perfect fit for Naranjo De Candido to explore her passions. An inspirational nuclear engineering course during her studies set her on the path toward studying the field as part of her master’s studies in Pisa. During her time there, she traveled around the world — to China as part of a student exchange program and to Switzerland and the United States for internships. “I formed a good background and curriculum and that allowed me to [gain admission] to MIT,” she says.

    At an internship at NASA’s Jet Propulsion Lab, she met an MIT mechanical engineering student who encouraged her to apply to the school for doctoral studies. Yet another mentor in the Italian nuclear sector had also suggested she apply to MIT to pursue nuclear engineering, so she decided to take the leap.

    And she is glad she did.

    Improving access to nuclear energy

    At MIT, Naranjo De Candido is working on improving access to nuclear energy by scaling down reactor size and, in the case of microreactors, making them mobile enough to travel to places where they’re needed. “The idea with a microreactor is that when the fuel is exhausted, you replace the entire microreactor onsite with a freshly fueled unit and take the old one back to a central facility where it’s going to be refueled,” she says. One of the early use cases for such microreactors has been remote mining sites which need reliable power 24/7.

    Modular reactors, about 10 times the size of microreactors, ensure access differently: The components can be manufactured and installed at scale. These reactors don’t just deliver electricity but also cater to the market for industrial heat, she says. “You can locate them close to industrial facilities and use the heat directly to power ammonia or hydrogen production or water desalinization for example,” she adds.

    As more of these modular reactors are installed, the industry is expected to expand to include enterprises that choose to simply build them and hand off operations to other companies. Whereas traditional nuclear energy reactors might have a full suite of staff on board, smaller-scale reactors such as modular ones cannot afford to staff in large numbers, so talent needs to be optimized and staff shared among many units. “Many of these companies are very interested in knowing exactly how many people and how much money to allocate, and how to organize resources to serve more than one reactor at the same time,” she says.

    Naranjo De Candido is working on a complex software program that factors in a large range of variables — from raw materials cost and worker training, reactor size, megawatt output and more — and leans on historical data to predict what resources newer plants might need. The program also informs operators about the tradeoffs they need to accept. For example, she explains, “if you reduce people below the typical level assigned, how does that impact the reliability of the plant, that is, the number of hours that it is able to operate without malfunctions and failures?”

    And managing and operating a nuclear reactor is particularly complex because safety standards limit how much time workers can work in certain areas and how safe zones need to be handled.

    “There’s a shortage of [qualified talent] in the industry so this is not just about reducing costs but also about making it possible to have plants out there,” Naranjo De Candido says. Different types of talent are needed, from professionals who specialize in mechanical components to electronic controls. The model that she is working on considers the need for such specialized skillsets as well as making room for cross-training talent in multiple fields as needed.

    In keeping with her goal of making nuclear energy more accessible, the optimization software will be open-source, available for all to use. “We want this to be a common ground for utilities and vendors and other players to be able to communicate better,” Naranjo De Candido says, Doing so will accelerate the operation of nuclear energy plants at scale, she hopes — an achievement that will come not a moment too soon. More

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    New study shows how universities are critical to emerging fusion industry

    A new study suggests that universities have an essential role to fulfill in the continued growth and success of any modern high-tech industry, and especially the nascent fusion industry; however, the importance of that role is not reflected in the number of fusion-oriented faculty and educational channels currently available. Academia’s responsiveness to the birth of other modern scientific fields, such as aeronautics and nuclear fission, provides a template for the steps universities can take to enable a robust fusion industry.

    Authored by Dennis Whyte, the Hitachi America Professor of Engineering and director of the Plasma Science and Fusion Center at MIT; Carlos Paz-Soldan, associate professor of applied physics and applied mathematics at Columbia University; and Brian D. Wirth, the Governor’s Chair Professor of Computational Nuclear Engineering at the University of Tennessee, the paper was recently published in the journal Physics of Plasmas as part of a special collection titled “Private Fusion Research: Opportunities and Challenges in Plasma Science.”

    With contributions from authors in academia, government, and private industry, the collection outlines a framework for public-private partnerships that will be essential for the success of the fusion industry.

    Now being seen as a potential source of unlimited green energy, fusion is the same process that powers the sun — hydrogen atoms combine to form helium, releasing vast amounts of clean energy in the form of light and heat.

    The excitement surrounding fusion’s arrival has resulted in the proliferation of dozens of for-profit companies positioning themselves at the forefront of the commercial fusion energy industry. In the near future, those companies will require a significant network of fusion-fluent workers to take on varied tasks requiring a range of skills.

    While the authors acknowledge the role of private industry, especially as an increasingly dominant source of research funding, they also show that academia is and will continue to be critical to industry’s development, and it cannot be decoupled from private industry’s growth. Despite the evidence of this burgeoning interest, the size and scale of the field’s academic network at U.S.-based universities is sparse.

    According to Whyte, “Diversifying the [fusion] field by adding more tracks for master’s students and undergraduates who can transition into industry more quickly is an important step.”

    An analysis found that while there are 57 universities in the United States active in plasma and fusion research, the average number of tenured or tenure-track plasma/fusion faculty at each institution is only two. By comparison, a sampling of US News and World Report’s top 10 programs for nuclear fission and aeronautics/astronautics found an average of nearly 20 faculty devoted to fission and 32 to aero/astro.

    “University programs in fusion and their sponsors need to up their game and hire additional faculty if they want to provide the necessary workforce to support a growing U.S. fusion industry,” adds Paz-Soldan.

    The growth and proliferation of those fields and others, such as computing and biotechnology, were historically in lockstep with the creation of academic programs that helped drive the fields’ progress and widespread acceptance. Creating a similar path for fusion is essential to ensuring its sustainable growth, and as Wirth notes, “that this growth should be pursued in a way that is interdisciplinary across numerous engineering and science disciplines.”

    At MIT, an example of that path is seen at the Plasma Science and Fusion Center.

    The center has deep historical ties to government research programs, and the largest fusion company in the world, Commonwealth Fusion Systems (CFS), was spun out of the PSFC by Whyte’s former students and an MIT postdoc. Whyte also serves as the primary investigator in collaborative research with CFS on SPARC, a proof-of-concept fusion platform for advancing tokamak science that is scheduled for completion in 2025.

    “Public and private roles in the fusion community are rapidly evolving in response to the growth of privately funded commercial product development,” says Michael Segal, head of open innovation at CFS. “The fusion industry will increasingly rely on its university partners to train students, work across diverse disciplines, and execute small and midsize programs at speed.”

    According to the authors, another key reason academia will remain essential to the continued growth and development of fusion is because it is unconflicted. Whyte comments, “Our mandate is sharing information and education, which means we have no competitive conflict and innovation can flow freely.” Furthermore, fusion science is inherently multidisciplinary: “[It] requires physicists, computer scientists, engineers, chemists, etc. and it’s easy to tap into all those disciplines in an academic environment where they’re all naturally rubbing elbows and collaborating.”

    Creating a new energy industry, however, will also require a workforce skilled in disciplines other than STEM, say the authors. As fusion companies continue to grow, they will need expertise in finance, safety, licensing, and market analysis. Any successful fusion enterprise will also have major geopolitical, societal, and economic impacts, all of which must be managed.

    Ultimately, there are several steps the authors identify to help build the connections between academia and industry that will be important going forward: The first is for universities to acknowledge the rapidly changing fusion landscape and begin to adapt. “Universities need to embrace the growth of the private sector in fusion, recognize the opportunities it provides, and seek out mutually beneficial partnerships,” says Paz-Soldan.

    The second step is to reconcile the mission of educational institutions — unconflicted open access — with condensed timelines and proprietary outputs that come with private partnerships. At the same time, the authors note that private fusion companies should embrace the transparency of academia by publishing and sharing the findings they can through peer-reviewed journals, which will be a necessary part of building the industry’s credibility.

    The last step, the authors say, is for universities to become more flexible and creative in their technology licensing strategies to ensure ideas and innovations find their way from the lab into industry.

    “As an industry, we’re in a unique position because everything is brand new,” Whyte says. “But we’re enough students of history that we can see what’s needed to succeed; quantifying the status of the private and academic landscape is an important strategic touchstone. By drawing attention to the current trajectory, hopefully we’ll be in a better position to work with our colleagues in the public and private sector and make better-informed choices about how to proceed.” More

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    Celebrating five years of MIT.nano

    There is vast opportunity for nanoscale innovation to transform the world in positive ways — expressed MIT.nano Director Vladimir Bulović as he posed two questions to attendees at the start of the inaugural Nano Summit: “Where are we heading? And what is the next big thing we can develop?”

    “The answer to that puts into perspective our main purpose — and that is to change the world,” Bulović, the Fariborz Maseeh Professor of Emerging Technologies, told an audience of more than 325 in-person and 150 virtual participants gathered for an exploration of nano-related research at MIT and a celebration of MIT.nano’s fifth anniversary.

    Over a decade ago, MIT embarked on a massive project for the ultra-small — building an advanced facility to support research at the nanoscale. Construction of MIT.nano in the heart of MIT’s campus, a process compared to assembling a ship in a bottle, began in 2015, and the facility launched in October 2018.

    Fast forward five years: MIT.nano now contains nearly 170 tools and instruments serving more than 1,200 trained researchers. These individuals come from over 300 principal investigator labs, representing more than 50 MIT departments, labs, and centers. The facility also serves external users from industry, other academic institutions, and over 130 startup and multinational companies.

    A cross section of these faculty and researchers joined industry partners and MIT community members to kick off the first Nano Summit, which is expected to become an annual flagship event for MIT.nano and its industry consortium. Held on Oct. 24, the inaugural conference was co-hosted by the MIT Industrial Liaison Program.

    Six topical sessions highlighted recent developments in quantum science and engineering, materials, advanced electronics, energy, biology, and immersive data technology. The Nano Summit also featured startup ventures and an art exhibition.

    Watch the videos here.

    Seeing and manipulating at the nanoscale — and beyond

    “We need to develop new ways of building the next generation of materials,” said Frances Ross, the TDK Professor in Materials Science and Engineering (DMSE). “We need to use electron microscopy to help us understand not only what the structure is after it’s built, but how it came to be. I think the next few years in this piece of the nano realm are going to be really amazing.”

    Speakers in the session “The Next Materials Revolution,” chaired by MIT.nano co-director for Characterization.nano and associate professor in DMSE James LeBeau, highlighted areas in which cutting-edge microscopy provides insights into the behavior of functional materials at the nanoscale, from anti-ferroelectrics to thin-film photovoltaics and 2D materials. They shared images and videos collected using the instruments in MIT.nano’s characterization suites, which were specifically designed and constructed to minimize mechanical-vibrational and electro-magnetic interference.

    Later, in the “Biology and Human Health” session chaired by Boris Magasanik Professor of Biology Thomas Schwartz, biologists echoed the materials scientists, stressing the importance of the ultra-quiet, low-vibration environment in Characterization.nano to obtain high-resolution images of biological structures.

    “Why is MIT.nano important for us?” asked Schwartz. “An important element of biology is to understand the structure of biology macromolecules. We want to get to an atomic resolution of these structures. CryoEM (cryo-electron microscopy) is an excellent method for this. In order to enable the resolution revolution, we had to get these instruments to MIT. For that, MIT.nano was fantastic.”

    Seychelle Vos, the Robert A. Swanson (1969) Career Development Professor of Life Sciences, shared CryoEM images from her lab’s work, followed by biology Associate Professor Joey Davis who spoke about image processing. When asked about the next stage for CryoEM, Davis said he’s most excited about in-situ tomography, noting that there are new instruments being designed that will improve the current labor-intensive process.

    To chart the future of energy, chemistry associate professor Yogi Surendranath is also using MIT.nano to see what is happening at the nanoscale in his research to use renewable electricity to change carbon dioxide into fuel.

    “MIT.nano has played an immense role, not only in facilitating our ability to make nanostructures, but also to understand nanostructures through advanced imaging capabilities,” said Surendranath. “I see a lot of the future of MIT.nano around the question of how nanostructures evolve and change under the conditions that are relevant to their function. The tools at MIT.nano can help us sort that out.”

    Tech transfer and quantum computing

    The “Advanced Electronics” session chaired by Jesús del Alamo, the Donner Professor of Science in the Department of Electrical Engineering and Computer Science (EECS), brought together industry partners and MIT faculty for a panel discussion on the future of semiconductors and microelectronics. “Excellence in innovation is not enough, we also need to be excellent in transferring these to the marketplace,” said del Alamo. On this point, panelists spoke about strengthening the industry-university connection, as well as the importance of collaborative research environments and of access to advanced facilities, such as MIT.nano, for these environments to thrive.

    The session came on the heels of a startup exhibit in which eleven START.nano companies presented their technologies in health, energy, climate, and virtual reality, among other topics. START.nano, MIT.nano’s hard-tech accelerator, provides participants use of MIT.nano’s facilities at a discounted rate and access to MIT’s startup ecosystem. The program aims to ease hard-tech startups’ transition from the lab to the marketplace, surviving common “valleys of death” as they move from idea to prototype to scaling up.

    When asked about the state of quantum computing in the “Quantum Science and Engineering” session, physics professor Aram Harrow related his response to these startup challenges. “There are quite a few valleys to cross — there are the technical valleys, and then also the commercial valleys.” He spoke about scaling superconducting qubits and qubits made of suspended trapped ions, and the need for more scalable architectures, which we have the ingredients for, he said, but putting everything together is quite challenging.

    Throughout the session, William Oliver, professor of physics and the Henry Ellis Warren (1894) Professor of Electrical Engineering and Computer Science, asked the panelists how MIT.nano can address challenges in assembly and scalability in quantum science.

    “To harness the power of students to innovate, you really need to allow them to get their hands dirty, try new things, try all their crazy ideas, before this goes into a foundry-level process,” responded Kevin O’Brien, associate professor in EECS. “That’s what my group has been working on at MIT.nano, building these superconducting quantum processors using the state-of-the art fabrication techniques in MIT.nano.”

    Connecting the digital to the physical

    In his reflections on the semiconductor industry, Douglas Carlson, senior vice president for technology at MACOM, stressed connecting the digital world to real-world application. Later, in the “Immersive Data Technology” session, MIT.nano associate director Brian Anthony explained how, at the MIT.nano Immersion Lab, researchers are doing just that.

    “We think about and facilitate work that has the human immersed between hardware, data, and experience,” said Anthony, principal research scientist in mechanical engineering. He spoke about using the capabilities of the Immersion Lab to apply immersive technologies to different areas — health, sports, performance, manufacturing, and education, among others. Speakers in this session gave specific examples in hardware, pediatric health, and opera.

    Anthony connected this third pillar of MIT.nano to the fab and characterization facilities, highlighting how the Immersion Lab supports work conducted in other parts of the building. The Immersion Lab’s strength, he said, is taking novel work being developed inside MIT.nano and bringing it up to the human scale to think about applications and uses.

    Artworks that are scientifically inspired

    The Nano Summit closed with a reception at MIT.nano where guests could explore the facility and gaze through the cleanroom windows, where users were actively conducting research. Attendees were encouraged to visit an exhibition on MIT.nano’s first- and second-floor galleries featuring work by students from the MIT Program in Art, Culture, and Technology (ACT) who were invited to utilize MIT.nano’s tool sets and environments as inspiration for art.

    In his closing remarks, Bulović reflected on the community of people who keep MIT.nano running and who are using the tools to advance their research. “Today we are celebrating the facility and all the work that has been done over the last five years to bring it to where it is today. It is there to function not just as a space, but as an essential part of MIT’s mission in research, innovation, and education. I hope that all of us here today take away a deep appreciation and admiration for those who are leading the journey into the nano age.” More

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    Team engineers nanoparticles using ion irradiation to advance clean energy and fuel conversion

    MIT researchers and colleagues have demonstrated a way to precisely control the size, composition, and other properties of nanoparticles key to the reactions involved in a variety of clean energy and environmental technologies. They did so by leveraging ion irradiation, a technique in which beams of charged particles bombard a material.

    They went on to show that nanoparticles created this way have superior performance over their conventionally made counterparts.

    “The materials we have worked on could advance several technologies, from fuel cells to generate CO2-free electricity to the production of clean hydrogen feedstocks for the chemical industry [through electrolysis cells],” says Bilge Yildiz, leader of the work and a professor in MIT’s departments of Nuclear Science and Engineering and Materials Science and Engineering.

    Critical catalyst

    Fuel and electrolysis cells both involve electrochemical reactions through three principal parts: two electrodes (a cathode and anode) separated by an electrolyte. The difference between the two cells is that the reactions involved run in reverse.

    The electrodes are coated with catalysts, or materials that make the reactions involved go faster. But a critical catalyst made of metal-oxide materials has been limited by challenges including low durability. “The metal catalyst particles coarsen at high temperatures, and you lose surface area and activity as a result,” says Yildiz, who is also affiliated with the Materials Research Laboratory and is an author of an open-access paper on the work published in the journal Energy & Environmental Science.

    Enter metal exsolution, which involves precipitating metal nanoparticles out of a host oxide onto the surface of the electrode. The particles embed themselves into the electrode, “and that anchoring makes them more stable,” says Yildiz. As a result, exsolution has “led to remarkable progress in clean energy conversion and energy-efficient computing devices,” the researchers write in their paper.

    However, controlling the precise properties of the resulting nanoparticles has been difficult. “We know that exsolution can give us stable and active nanoparticles, but the challenging part is really to control it. The novelty of this work is that we’ve found a tool — ion irradiation — that can give us that control,” says Jiayue Wang PhD ’22, first author of the paper. Wang, who conducted the work while earning his PhD in the MIT Department of Nuclear Science and Engineering, is now a postdoc at Stanford University.

    Sossina Haile ’86, PhD ’92, the Walter P. Murphy Professor of Materials Science and Engineering at Northwestern University, who was not involved in the current work, says:

    “Metallic nanoparticles serve as catalysts in a whole host of reactions, including the important reaction of splitting water to generate hydrogen for energy storage. In this work, Yildiz and colleagues have created an ingenious method for controlling the way that nanoparticles form.”

    Haile continues, “the community has shown that exsolution results in structurally stable nanoparticles, but the process is not easy to control, so one doesn’t necessarily get the optimal number and size of particles. Using ion irradiation, this group was able to precisely control the features of the nanoparticles, resulting in excellent catalytic activity for water splitting.”

    What they did

    The researchers found that aiming a beam of ions at the electrode while simultaneously exsolving metal nanoparticles onto the electrode’s surface allowed them to control several properties of the resulting nanoparticles.

    “Through ion-matter interactions, we have successfully engineered the size, composition, density, and location of the exsolved nanoparticles,” the team writes in Energy & Environmental Science.

    For example, they could make the particles much smaller — down to 2 billionths of a meter in diameter — than those made using conventional thermal exsolution methods alone. Further, they were able to change the composition of the nanoparticles by irradiating with specific elements. They demonstrated this with a beam of nickel ions that implanted nickel into the exsolved metal nanoparticle. As a result, they demonstrated a direct and convenient way to engineer the composition of exsolved nanoparticles.

    “We want to have multi-element nanoparticles, or alloys, because they usually have higher catalytic activity,” Yildiz says. “With our approach, the exsolution target does not have to be dependent on the substrate oxide itself.” Irradiation opens the door to many more compositions. “We can pretty much choose any oxide and any ion that we can irradiate with and exsolve that,” says Yildiz.

    The team also found that ion irradiation forms defects in the electrode itself. And these defects provide additional nucleation sites, or places for the exsolved nanoparticles to grow from, increasing the density of the resulting nanoparticles.

    Irradiation could also allow extreme spatial control over the nanoparticles. “Because you can focus the ion beam, you can imagine that you could ‘write’ with it to form specific nanostructures,” says Wang. “We did a preliminary demonstration [of that], but we believe it has potential to realize well-controlled micro- and nano-structures.”

    The team also showed that the nanoparticles they created with ion irradiation had superior catalytic activity over those created by conventional thermal exsolution alone.

    Additional MIT authors of the paper are Kevin B. Woller, a principal research scientist at the Plasma Science and Fusion Center (PSFC), home to the equipment used for ion irradiation; Abinash Kumar PhD ’22, who received his PhD from the Department of Materials Science and Engineering (DMSE) and is now at Oak Ridge National Laboratory; and James M. LeBeau, an associate professor in DMSE. Other authors are Zhan Zhang and Hua Zhou of Argonne National Laboratory, and Iradwikanari Waluyo and Adrian Hunt of Brookhaven National Laboratory.

    This work was funded by the OxEon Corp. and MIT’s PSFC. The research also used resources supported by the U.S. Department of Energy Office of Science, MIT’s Materials Research Laboratory, and MIT.nano. The work was performed, in part, at Harvard University through a network funded by the National Science Foundation. More

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    Dennis Whyte steps down as director of the Plasma Science and Fusion Center

    Dennis Whyte, who spearheaded the development of the world’s most powerful fusion electromagnet and grew the MIT Plasma Science and Fusion Center’s research volume by more than 50 percent, has announced he will be stepping down as the center’s director at the end of the year in order to devote his full attention to teaching, engaging in cutting-edge fusion research, and pursuing entrepreneurial activities at the PSFC.

    “The reason I came to MIT as a faculty member in ’06 was because of the PSFC and the very special place it held and still holds in fusion,” says Whyte, the Hitachi America Professor of Engineering in the Department of Nuclear Science and Engineering. When he was appointed director of the PSFC in 2015, Whyte saw it as an opportunity to realize even more of the PSFC’s potential: “After 10 years I think we’ve seen that dream come to life. Research and entrepreneurship are stronger than ever.”

    Whyte’s passion has always been for fusion — the process by which light elements combine to form heavier ones, releasing massive amounts of energy. One hundred years ago fusion was solely the provenance of astronomers’ speculation; through the efforts of generations of scientists and engineers, fusion now holds the potential to offer humanity an entirely new source of clean, abundant energy — and Whyte has been at the forefront of that effort.

    “Fusion’s challenges require interdisciplinary work, so it’s always fresh, and you get these unexpected intersections that can have wild outcomes. As an inherently curious person, fusion is perfect for me.”

    Whyte’s enthusiasm is legendary, especially when it comes to teaching. The effects of that enthusiasm are easy to see: At the start of his tenure, only a handful of students chose to pursue plasma physics and fusion science. Since then, the number of students has ballooned, and this year nearly 100 students from six departments are working with 15 faculty members.

    Of the growth, Whyte says, “It’s not just that we have more students; it’s that they’re working on more diverse topics, and their passion to make fusion a reality is the best part of the PSFC. Seeing full seminars and classes is fundamentally why I’m here.”

    Even as he managed the directorship and pursued his own scholarly work, Whyte remained active in the classroom and continued advising students. Zach Hartwig, a former student who is now a PSFC researcher and MIT faculty member himself, recalled his first meeting with Whyte as an incoming PhD student: “I had to choose between several projects and advisors and meeting Dennis made my decision easy. He catapulted out of his chair and started sketching his vision for a new fusion diagnostic that many people thought was crazy. His passion and eagerness to tackle only the most difficult problems in the field was immediately tangible.”

    For the past 13 years Whyte has offered a fusion technology design class that has generated several key breakthroughs, including liquid immersion blankets essential for converting fusion energy to heat, inside launch radio frequency systems used to stabilize fusing plasmas, and high-temperature superconducting electromagnets that have opened the door to the possibility of fusion devices that are not only smaller, but also more powerful and efficient.

    In fact, the potential of these electromagnets was significant enough that Whyte, an MIT postdoc, and three of Whyte’s former students (Hartwig among them) spun out a private fusion company to fully realize the magnets’ capabilities. Commonwealth Fusion Systems (CFS) both launched and signed a cooperative research agreement with the PSFC in 2018, and the founders’ vision parlayed into significant external investment, allowing a coalition of CFS and PSFC researchers to refine and develop the electromagnets first conceived in Whyte’s class.

    Three years later, after a historic day of testing, the magnet produced a field strength of 20 tesla, making it the most powerful fusion superconducting electromagnet in the world. According to Whyte, “The success of the TFMC magnet is an encapsulation of everything PSFC. It would’ve been impossible for a single investigator, or a lone spin-out, but we brought together all these disciplines in a team that could execute innovatively and incredibly quickly. We shortened the timescale not just for this project, but for fusion as a whole.”

    CFS remains an important collaborator, accounting for approximately 20 percent of the PSFC’s current research portfolio. While Whyte has no financial stake in the company, he remains a principal investigator on CFS’s SPARC project, a proof-of-concept fusion device predicted to produce more energy than it consumes, ready in 2025. SPARC is the lead-up to ARC, CFS’s commercially scalable fusion power plant planned to arrive in the early 2030s.

    The collaboration between CFS and MIT followed a blueprint that had been piloted more than a decade prior, when the Italian energy company Eni S.p.A signed on as a founding member of the MIT Energy Initiative to develop low-carbon technologies. After many years of successfully working in tandem with MITEI to advance renewable energy research, in 2018 Eni made a significant investment in a young CFS to assist in realizing commercial fusion power, which in turn indirectly funded PSFC research; Eni also collaborated directly with the PSFC to create the Laboratory for Innovative Fusion Technologies, which remains active.

    Whyte believes that “thoughtful and meaningful collaboration with the energy industry can make a difference with research and climate change. Industry engagement is very relevant — it changed both of us. Now Eni has fusion in their portfolio.” The arrangement is a demonstration of how public-private collaborations can accelerate the progress of fusion science, and ultimately the arrival of fusion power.

    Whyte’s move to diversify collaborators, leverage the PSFC’s strength as a multidisciplinary hub, and expand research volume was essential to the center’s survival and growth. Early in his tenure, a shift in funding priorities necessitated the shutdown of Alcator C-Mod, the fusion research device in operation at the PSFC for 23 years — though not before C-Mod set the world record for plasma pressure on its last day of operation. Through this transition, Whyte and the members of his leadership team were able to keep the PSFC whole.

    One alumnus was a particular source of inspiration to Whyte during that time: “Reinier [Beeuwkes] said to me, ‘what you’re doing doesn’t just matter to students and MIT, it matters to the world.’ That was so meaningful, and his words really sustained me when I was feeling major doubt.” In 2022 Beeuwkes won the MIT Alumni Better World Service Award for his support of fusion and the PSFC. Since 2018, sponsored research at the PSFC has more than doubled, as have the number of personnel.

    Whyte’s determination to build and maintain a strong community is a prevailing feature of his leadership. Matt Fulton, who started at the PSFC in 1987 and is now director of operations, says of Whyte, “You want a leader like Dennis on your worst days. We were staring down disaster and he had a plan to hold the PSFC together, and somehow it worked. The research was important, but the people have always been more important to him. We’re so lucky to have him.”

    The Office of the Vice President for Research is launching a search for the PSFC’s next leader. Should the search extend beyond the end of the year, an interim director will be appointed.  

    “As MIT works to magnify its impact in the areas of climate and sustainability, Dennis has built the PSFC into an extraordinary resource for the Institute to draw upon,” says Maria T. Zuber, MIT’s vice president for research. “His leadership has positioned MIT on the leading edge of fusion research and the emerging commercial fusion industry, and while the nature of his contributions will change, … the value he brings to the MIT community will remain clear. As Dennis steps down as director, the PSFC is ascendant.”  More

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    Forging climate connections across the Institute

    Climate change is the ultimate cross-cutting issue: Not limited to any one discipline, it ranges across science, technology, policy, culture, human behavior, and well beyond. The response to it likewise requires an all-of-MIT effort.

    Now, to strengthen such an effort, a new grant program spearheaded by the Climate Nucleus, the faculty committee charged with the oversight and implementation of Fast Forward: MIT’s Climate Action Plan for the Decade, aims to build up MIT’s climate leadership capacity while also supporting innovative scholarship on diverse climate-related topics and forging new connections across the Institute.

    Called the Fast Forward Faculty Fund (F^4 for short), the program has named its first cohort of six faculty members after issuing its inaugural call for proposals in April 2023. The cohort will come together throughout the year for climate leadership development programming and networking. The program provides financial support for graduate students who will work with the faculty members on the projects — the students will also participate in leadership-building activities — as well as $50,000 in flexible, discretionary funding to be used to support related activities. 

    “Climate change is a crisis that truly touches every single person on the planet,” says Noelle Selin, co-chair of the nucleus and interim director of the Institute for Data, Systems, and Society. “It’s therefore essential that we build capacity for every member of the MIT community to make sense of the problem and help address it. Through the Fast Forward Faculty Fund, our aim is to have a cohort of climate ambassadors who can embed climate everywhere at the Institute.”

    F^4 supports both faculty who would like to begin doing climate-related work, as well as faculty members who are interested in deepening their work on climate. The program has the core goal of developing cohorts of F^4 faculty and graduate students who, in addition to conducting their own research, will become climate leaders at MIT, proactively looking for ways to forge new climate connections across schools, departments, and disciplines.

    One of the projects, “Climate Crisis and Real Estate: Science-based Mitigation and Adaptation Strategies,” led by Professor Siqi Zheng of the MIT Center for Real Estate in collaboration with colleagues from the MIT Sloan School of Management, focuses on the roughly 40 percent of carbon dioxide emissions that come from the buildings and real estate sector. Zheng notes that this sector has been slow to respond to climate change, but says that is starting to change, thanks in part to the rising awareness of climate risks and new local regulations aimed at reducing emissions from buildings.

    Using a data-driven approach, the project seeks to understand the efficient and equitable market incentives, technology solutions, and public policies that are most effective at transforming the real estate industry. Johnattan Ontiveros, a graduate student in the Technology and Policy Program, is working with Zheng on the project.

    “We were thrilled at the incredible response we received from the MIT faculty to our call for proposals, which speaks volumes about the depth and breadth of interest in climate at MIT,” says Anne White, nucleus co-chair and vice provost and associate vice president for research. “This program makes good on key commitments of the Fast Forward plan, supporting cutting-edge new work by faculty and graduate students while helping to deepen the bench of climate leaders at MIT.”

    During the 2023-24 academic year, the F^4 faculty and graduate student cohorts will come together to discuss their projects, explore opportunities for collaboration, participate in climate leadership development, and think proactively about how to deepen interdisciplinary connections among MIT community members interested in climate change.

    The six inaugural F^4 awardees are:

    Professor Tristan Brown, History Section: Humanistic Approaches to the Climate Crisis  

    With this project, Brown aims to create a new community of practice around narrative-centric approaches to environmental and climate issues. Part of a broader humanities initiative at MIT, it brings together a global working group of interdisciplinary scholars, including Serguei Saavedra (Department of Civil and Environmental Engineering) and Or Porath (Tel Aviv University; Religion), collectively focused on examining the historical and present links between sacred places and biodiversity for the purposes of helping governments and nongovernmental organizations formulate better sustainability goals. Boyd Ruamcharoen, a PhD student in the History, Anthropology, and Science, Technology, and Society (HASTS) program, will work with Brown on this project.

    Professor Kerri Cahoy, departments of Aeronautics and Astronautics and Earth, Atmospheric, and Planetary Sciences (AeroAstro): Onboard Autonomous AI-driven Satellite Sensor Fusion for Coastal Region Monitoring

    The motivation for this project is the need for much better data collection from satellites, where technology can be “20 years behind,” says Cahoy. As part of this project, Cahoy will pursue research in the area of autonomous artificial intelligence-enabled rapid sensor fusion (which combines data from different sensors, such as radar and cameras) onboard satellites to improve understanding of the impacts of climate change, specifically sea-level rise and hurricanes and flooding in coastal regions. Graduate students Madeline Anderson, a PhD student in electrical engineering and computer science (EECS), and Mary Dahl, a PhD student in AeroAstro, will work with Cahoy on this project.

    Professor Priya Donti, Department of Electrical Engineering and Computer Science: Robust Reinforcement Learning for High-Renewables Power Grids 

    With renewables like wind and solar making up a growing share of electricity generation on power grids, Donti’s project focuses on improving control methods for these distributed sources of electricity. The research will aim to create a realistic representation of the characteristics of power grid operations, and eventually inform scalable operational improvements in power systems. It will “give power systems operators faith that, OK, this conceptually is good, but it also actually works on this grid,” says Donti. PhD candidate Ana Rivera from EECS is the F^4 graduate student on the project.

    Professor Jason Jackson, Department of Urban Studies and Planning (DUSP): Political Economy of the Climate Crisis: Institutions, Power and Global Governance

    This project takes a political economy approach to the climate crisis, offering a distinct lens to examine, first, the political governance challenge of mobilizing climate action and designing new institutional mechanisms to address the global and intergenerational distributional aspects of climate change; second, the economic challenge of devising new institutional approaches to equitably finance climate action; and third, the cultural challenge — and opportunity — of empowering an adaptive socio-cultural ecology through traditional knowledge and local-level social networks to achieve environmental resilience. Graduate students Chen Chu and Mrinalini Penumaka, both PhD students in DUSP, are working with Jackson on the project.

    Professor Haruko Wainwright, departments of Nuclear Science and Engineering (NSE) and Civil and Environmental Engineering: Low-cost Environmental Monitoring Network Technologies in Rural Communities for Addressing Climate Justice 

    This project will establish a community-based climate and environmental monitoring network in addition to a data visualization and analysis infrastructure in rural marginalized communities to better understand and address climate justice issues. The project team plans to work with rural communities in Alaska to install low-cost air and water quality, weather, and soil sensors. Graduate students Kay Whiteaker, an MS candidate in NSE, and Amandeep Singh, and MS candidate in System Design and Management at Sloan, are working with Wainwright on the project, as is David McGee, professor in earth, atmospheric, and planetary sciences.

    Professor Siqi Zheng, MIT Center for Real Estate and DUSP: Climate Crisis and Real Estate: Science-based Mitigation and Adaptation Strategies 

    See the text above for the details on this project. More

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    Engineers develop an efficient process to make fuel from carbon dioxide

    The search is on worldwide to find ways to extract carbon dioxide from the air or from power plant exhaust and then make it into something useful. One of the more promising ideas is to make it into a stable fuel that can replace fossil fuels in some applications. But most such conversion processes have had problems with low carbon efficiency, or they produce fuels that can be hard to handle, toxic, or flammable.

    Now, researchers at MIT and Harvard University have developed an efficient process that can convert carbon dioxide into formate, a liquid or solid material that can be used like hydrogen or methanol to power a fuel cell and generate electricity. Potassium or sodium formate, already produced at industrial scales and commonly used as a de-icer for roads and sidewalks, is nontoxic, nonflammable, easy to store and transport, and can remain stable in ordinary steel tanks to be used months, or even years, after its production.

    The new process, developed by MIT doctoral students Zhen Zhang, Zhichu Ren, and Alexander H. Quinn; Harvard University doctoral student Dawei Xi; and MIT Professor Ju Li, is described this week in an open-access paper in Cell Reports Physical Science. The whole process — including capture and electrochemical conversion of the gas to a solid formate powder, which is then used in a fuel cell to produce electricity — was demonstrated at a small, laboratory scale. However, the researchers expect it to be scalable so that it could provide emissions-free heat and power to individual homes and even be used in industrial or grid-scale applications.

    Other approaches to converting carbon dioxide into fuel, Li explains, usually involve a two-stage process: First the gas is chemically captured and turned into a solid form as calcium carbonate, then later that material is heated to drive off the carbon dioxide and convert it to a fuel feedstock such as carbon monoxide. That second step has very low efficiency, typically converting less than 20 percent of the gaseous carbon dioxide into the desired product, Li says.

    By contrast, the new process achieves a conversion of well over 90 percent and eliminates the need for the inefficient heating step by first converting the carbon dioxide into an intermediate form, liquid metal bicarbonate. That liquid is then electrochemically converted into liquid potassium or sodium formate in an electrolyzer that uses low-carbon electricity, e.g. nuclear, wind, or solar power. The highly concentrated liquid potassium or sodium formate solution produced can then be dried, for example by solar evaporation, to produce a solid powder that is highly stable and can be stored in ordinary steel tanks for up to years or even decades, Li says.

    Several steps of optimization developed by the team made all the difference in changing an inefficient chemical-conversion process into a practical solution, says Li, who holds joint appointments in the departments of Nuclear Science and Engineering and of Materials Science and Engineering.

    The process of carbon capture and conversion involves first an alkaline solution-based capture that concentrates carbon dioxide, either from concentrated streams such as from power plant emissions or from very low-concentration sources, even open air, into the form of a liquid metal-bicarbonate solution. Then, through the use of a cation-exchange membrane electrolyzer, this bicarbonate is electrochemically converted into solid formate crystals with a carbon efficiency of greater than 96 percent, as confirmed in the team’s lab-scale experiments.

    These crystals have an indefinite shelf life, remaining so stable that they could be stored for years, or even decades, with little or no loss. By comparison, even the best available practical hydrogen storage tanks allow the gas to leak out at a rate of about 1 percent per day, precluding any uses that would require year-long storage, Li says. Methanol, another widely explored alternative for converting carbon dioxide into a fuel usable in fuel cells, is a toxic substance that cannot easily be adapted to use in situations where leakage could pose a health hazard. Formate, on the other hand, is widely used and considered benign, according to national safety standards.

    Several improvements account for the greatly improved efficiency of this process. First, a careful design of the membrane materials and their configuration overcomes a problem that previous attempts at such a system have encountered, where a buildup of certain chemical byproducts changes the pH, causing the system to steadily lose efficiency over time. “Traditionally, it is difficult to achieve long-term, stable, continuous conversion of the feedstocks,” Zhang says. “The key to our system is to achieve a pH balance for steady-state conversion.”

    To achieve that, the researchers carried out thermodynamic modeling to design the new process so that it is chemically balanced and the pH remains at a steady state with no shift in acidity over time. It can therefore continue operating efficiently over long periods. In their tests, the system ran for over 200 hours with no significant decrease in output. The whole process can be done at ambient temperatures and relatively low pressures (about five times atmospheric pressure).

    Another issue was that unwanted side reactions produced other chemical products that were not useful, but the team figured out a way to prevent these side reactions by the introduction of an extra “buffer” layer of bicarbonate-enriched fiberglass wool that blocked these reactions.

    The team also built a fuel cell specifically optimized for the use of this formate fuel to produce electricity. The stored formate particles are simply dissolved in water and pumped into the fuel cell as needed. Although the solid fuel is much heavier than pure hydrogen, when the weight and volume of the high-pressure gas tanks needed to store hydrogen is considered, the end result is an electricity output near parity for a given storage volume, Li says.

    The formate fuel can potentially be adapted for anything from home-sized units to large scale industrial uses or grid-scale storage systems, the researchers say. Initial household applications might involve an electrolyzer unit about the size of a refrigerator to capture and convert the carbon dioxide into formate, which could be stored in an underground or rooftop tank. Then, when needed, the powdered solid would be mixed with water and fed into a fuel cell to provide power and heat. “This is for community or household demonstrations,” Zhang says, “but we believe that also in the future it may be good for factories or the grid.”

    “The formate economy is an intriguing concept because metal formate salts are very benign and stable, and a compelling energy carrier,” says Ted Sargent, a professor of chemistry and of electrical and computer engineering at Northwestern University, who was not associated with this work. “The authors have demonstrated enhanced efficiency in liquid-to-liquid conversion from bicarbonate feedstock to formate, and have demonstrated these fuels can be used later to produce electricity,” he says.

    The work was supported by the U.S. Department of Energy Office of Science. More