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    Elsa Olivetti appointed associate dean of engineering

    Elsa Olivetti, the Jerry McAfee (1940) Professor in Engineering in the Department of Materials Science and Engineering, has been appointed as associate dean of engineering, effective Sept. 1.

    As associate dean, Olivetti will oversee a number of strategically important programs and initiatives across MIT’s School of Engineering. She will help lead and shape school-wide efforts related to climate and sustainability. In close collaboration with Nandi Bynoe, the assistant dean for diversity, equity, and inclusion; the school’s DEI faculty lead; and various program faculty leads, Olivetti will oversee the school’s DEI activities and programs. She will also assist with the faculty promotion process and will support both faculty and students across the school with regards fellowships, awards, and honors.

    “Professor Olivetti has demonstrated tremendous leadership abilities, particularly as co-director of the MIT Climate and Sustainability Consortium. Her contributions as a researcher, educator, and leader at MIT have been substantial,” says Anantha Chandrakasan, dean of the School of Engineering and the Vannevar Bush Professor of Electrical Engineering and Computer Science. “I am thrilled to welcome her to the School of Engineering leadership team and look forward to closely with her in this new role.”

    Olivetti first joined MIT as a graduate student after receiving her bachelor’s degree in engineering science from the University of Virginia. As a PhD student in the Department of Materials Science and Engineering (DMSE), her research focused on electrochemistry in inorganic materials for use in lithium-ion batteries. Through postdoctoral research and a staff scientist position with the MIT Materials System Laboratory beginning in 2009, Olivetti developed methods for streamlined carbon footprinting of electronics, a method that is still used widely by the electronics industry.

    In 2014, Olivetti joined the DMSE faculty, where her team works in sustainable and scalable design, processing, and manufacturing of materials use across industries. The Olivetti Group develops experimental and analytical methods for efficient use of industrial waste and recycled materials in concrete, metals, and plastic guiding decisions on a plant floor to policy makers.

    Olivetti’s team has also developed methods to automatically learn from texts within materials ranging from inorganic materials synthesis, zeolites, solid state batteries, and cement. Her work uses an interdisciplinary approach combining industrial ecology with materials science and engineering to inform and then mitigate the environmental and economic impact of materials.

    Olivetti has lead climate and sustainability efforts across the Institute. She serves as the co-director of the MIT Climate and Sustainability Consortium (MCSC). Launched in 2021, the MCSC fosters collaboration between academia and industry in an effort to accelerate real-world solutions for the climate crisis at scale. Under Olivetti’s leadership alongside co-director Jeffrey Grossman, the Morton and Claire Goulder and Family Professor in Environmental Systems, and executive director Jeremy Gregory, the consortium has grown to 18 member companies and has provided 20 research projects with seed funding. It has also launched programs such as the MCSC Climate and Sustainability Scholars Program for undergraduate students and the MCSC Impact Fellows Program for postdocs.

    In addition to her leadership at the MCSC, Olivetti is a member of the MIT Climate Nucleus, a faculty committee responsible for the implementation of “Fast Forward: MIT’s Climate Action Plan for the Decade.”

    A dedicated educator, Olivetti has made significant contributions to MIT’s material science and engineering education. She was instrumental in the development of a refined DMSE undergraduate curriculum. She also launched a new class 3.081 (Industrial Ecology of Materials) and served as a founding thread lead for MIT New Engineering Education Transformation’s Advanced Materials Machines program. Olivetti launched “Course 3 Industry Seminars,” which provide undergraduate students an opportunity to learn from industry leaders in fields like manufacturing and environmental consulting.

    Throughout her career, Olivetti has received numerous awards and honors for both her commitment to students and her research contributions. She is the recipient of the 2017 Earll M. Murman Award for Excellence in Undergraduate Advising, a 2020 Paul Gray Award for Public Service, the 2021 Bose Teaching Award, 2021 MacVicar Faculty Fellowship, and the 2023 Capers (1976) and Marion McDonald Award for Excellence in Mentoring and Advising. She also received an Early Career Faculty Fellowship from the Minerals, Metals and Materials Society as well as a National Science Foundation Early Career Development Award.

    Olivetti joins Dean Chandrakasan and Deputy Dean Maria Yang, the Gail E. Kendall (1978) Professor, on the School of Engineering faculty leadership team. More

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    MIT engineers create an energy-storing supercapacitor from ancient materials

    Two of humanity’s most ubiquitous historical materials, cement and carbon black (which resembles very fine charcoal), may form the basis for a novel, low-cost energy storage system, according to a new study. The technology could facilitate the use of renewable energy sources such as solar, wind, and tidal power by allowing energy networks to remain stable despite fluctuations in renewable energy supply.

    The two materials, the researchers found, can be combined with water to make a supercapacitor — an alternative to batteries — that could provide storage of electrical energy. As an example, the MIT researchers who developed the system say that their supercapacitor could eventually be incorporated into the concrete foundation of a house, where it could store a full day’s worth of energy while adding little (or no) to the cost of the foundation and still providing the needed structural strength. The researchers also envision a concrete roadway that could provide contactless recharging for electric cars as they travel over that road.

    The simple but innovative technology is described this week in the journal PNAS, in a paper by MIT professors Franz-Josef Ulm, Admir Masic, and Yang-Shao Horn, and four others at MIT and at the Wyss Institute for Biologically Inspired Engineering.

    Capacitors are in principle very simple devices, consisting of two electrically conductive plates immersed in an electrolyte and separated by a membrane. When a voltage is applied across the capacitor, positively charged ions from the electrolyte accumulate on the negatively charged plate, while the positively charged plate accumulates negatively charged ions. Since the membrane in between the plates blocks charged ions from migrating across, this separation of charges creates an electric field between the plates, and the capacitor becomes charged. The two plates can maintain this pair of charges for a long time and then deliver them very quickly when needed. Supercapacitors are simply capacitors that can store exceptionally large charges.

    The amount of power a capacitor can store depends on the total surface area of its conductive plates. The key to the new supercapacitors developed by this team comes from a method of producing a cement-based material with an extremely high internal surface area due to a dense, interconnected network of conductive material within its bulk volume. The researchers achieved this by introducing carbon black — which is highly conductive — into a concrete mixture along with cement powder and water, and letting it cure. The water naturally forms a branching network of openings within the structure as it reacts with cement, and the carbon migrates into these spaces to make wire-like structures within the hardened cement. These structures have a fractal-like structure, with larger branches sprouting smaller branches, and those sprouting even smaller branchlets, and so on, ending up with an extremely large surface area within the confines of a relatively small volume. The material is then soaked in a standard electrolyte material, such as potassium chloride, a kind of salt, which provides the charged particles that accumulate on the carbon structures. Two electrodes made of this material, separated by a thin space or an insulating layer, form a very powerful supercapacitor, the researchers found.

    The two plates of the capacitor function just like the two poles of a rechargeable battery of equivalent voltage: When connected to a source of electricity, as with a battery, energy gets stored in the plates, and then when connected to a load, the electrical current flows back out to provide power.

    “The material is fascinating,” Masic says, “because you have the most-used manmade material in the world, cement, that is combined with carbon black, that is a well-known historical material — the Dead Sea Scrolls were written with it. You have these at least two-millennia-old materials that when you combine them in a specific manner you come up with a conductive nanocomposite, and that’s when things get really interesting.”

    As the mixture sets and cures, he says, “The water is systematically consumed through cement hydration reactions, and this hydration fundamentally affects nanoparticles of carbon because they are hydrophobic (water repelling).” As the mixture evolves, “the carbon black is self-assembling into a connected conductive wire,” he says. The process is easily reproducible, with materials that are inexpensive and readily available anywhere in the world. And the amount of carbon needed is very small — as little as 3 percent by volume of the mix — to achieve a percolated carbon network, Masic says.

    Supercapacitors made of this material have great potential to aid in the world’s transition to renewable energy, Ulm says. The principal sources of emissions-free energy, wind, solar, and tidal power, all produce their output at variable times that often do not correspond to the peaks in electricity usage, so ways of storing that power are essential. “There is a huge need for big energy storage,” he says, and existing batteries are too expensive and mostly rely on materials such as lithium, whose supply is limited, so cheaper alternatives are badly needed. “That’s where our technology is extremely promising, because cement is ubiquitous,” Ulm says.

    The team calculated that a block of nanocarbon-black-doped concrete that is 45 cubic meters (or yards) in size — equivalent to a cube about 3.5 meters across — would have enough capacity to store about 10 kilowatt-hours of energy, which is considered the average daily electricity usage for a household. Since the concrete would retain its strength, a house with a foundation made of this material could store a day’s worth of energy produced by solar panels or windmills and allow it to be used whenever it’s needed. And, supercapacitors can be charged and discharged much more rapidly than batteries.

    After a series of tests used to determine the most effective ratios of cement, carbon black, and water, the team demonstrated the process by making small supercapacitors, about the size of some button-cell batteries, about 1 centimeter across and 1 millimeter thick, that could each be charged to 1 volt, comparable to a 1-volt battery. They then connected three of these to demonstrate their ability to light up a 3-volt light-emitting diode (LED). Having proved the principle, they now plan to build a series of larger versions, starting with ones about the size of a typical 12-volt car battery, then working up to a 45-cubic-meter version to demonstrate its ability to store a house-worth of power.

    There is a tradeoff between the storage capacity of the material and its structural strength, they found. By adding more carbon black, the resulting supercapacitor can store more energy, but the concrete is slightly weaker, and this could be useful for applications where the concrete is not playing a structural role or where the full strength-potential of concrete is not required. For applications such as a foundation, or structural elements of the base of a wind turbine, the “sweet spot” is around 10 percent carbon black in the mix, they found.

    Another potential application for carbon-cement supercapacitors is for building concrete roadways that could store energy produced by solar panels alongside the road and then deliver that energy to electric vehicles traveling along the road using the same kind of technology used for wirelessly rechargeable phones. A related type of car-recharging system is already being developed by companies in Germany and the Netherlands, but using standard batteries for storage.

    Initial uses of the technology might be for isolated homes or buildings or shelters far from grid power, which could be powered by solar panels attached to the cement supercapacitors, the researchers say.

    Ulm says that the system is very scalable, as the energy-storage capacity is a direct function of the volume of the electrodes. “You can go from 1-millimeter-thick electrodes to 1-meter-thick electrodes, and by doing so basically you can scale the energy storage capacity from lighting an LED for a few seconds, to powering a whole house,” he says.

    Depending on the properties desired for a given application, the system could be tuned by adjusting the mixture. For a vehicle-charging road, very fast charging and discharging rates would be needed, while for powering a home “you have the whole day to charge it up,” so slower-charging material could be used, Ulm says.

    “So, it’s really a multifunctional material,” he adds. Besides its ability to store energy in the form of supercapacitors, the same kind of concrete mixture can be used as a heating system, by simply applying electricity to the carbon-laced concrete.

    Ulm sees this as “a new way of looking toward the future of concrete as part of the energy transition.”

    The research team also included postdocs Nicolas Chanut and Damian Stefaniuk at MIT’s Department of Civil and Environmental Engineering, James Weaver at the Wyss Institute, and Yunguang Zhu in MIT’s Department of Mechanical Engineering. The work was supported by the MIT Concrete Sustainability Hub, with sponsorship by the Concrete Advancement Foundation. More

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    3 Questions: What’s it like winning the MIT $100K Entrepreneurship Competition?

    Solar power plays a major role in nearly every roadmap for global decarbonization. But solar panels are large, heavy, and expensive, which limits their deployment. But what if solar panels looked more like a yoga mat?

    Such a technology could be transported in a roll, carried to the top of a building, and rolled out across the roof in a matter of minutes, slashing installation costs and dramatically expanding the places where rooftop solar makes sense.

    That was the vision laid out by the MIT spinout Active Surfaces as part of the winning pitch at this year’s MIT $100K Entrepreneurship Competition, which took place May 15. The company is leveraging materials science and manufacturing innovations from labs across MIT to make ultra-thin, lightweight, and durable solar a reality.

    The $100K is one of MIT’s most visible entrepreneurship competitions, and past winners say the prize money is only part of the benefit that winning brings to a burgeoning new company. MIT News sat down with Active Surface founders Shiv Bhakta, a graduate student in MIT’s Leaders for Global Operations dual-degree program within the MIT Sloan School of Management and Department of Civil and Environmental Engineering, and Richard Swartwout SM ’18 PhD ’21, an electrical engineering and computer science graduate and former Research Laboratory of Electronics postdoc and MIT.nano innovation fellow, to learn what the last couple of months have been like since they won.

    Q: What is Active Surfaces’ solution, and what is its potential?

    Bhakta: We’re commercializing an ultrathin film, flexible solar technology. Solar is one of the most broadly distributed resources in the world, but access is limited today. It’s heavy — it weighs 50 to 60 pounds a panel — it requires large teams to move around, and the form factor can only be deployed in specific environments.

    Our approach is to develop a solar technology for the built environment. In a nutshell, we can create flexible solar panels that are as thin as paper, just as efficient as traditional panels, and at unprecedented cost floors, all while being applied to any surface. Same area, same power. That’s our motto.

    When I came to MIT, my north star was to dive deeper in my climate journey and help make the world a better, greener place. Now, as we build Active Surfaces, I’m excited to see that dream taking shape. The prospect of transforming any surface into an energy source, thereby expanding solar accessibility globally, holds the promise of significantly reducing CO2 emissions at a gigaton scale. That’s what gets me out of bed in the morning.

    Swartwout: Solar and a lot of other renewables tend to be pretty land-inefficient. Solar 1.0 is using low hanging fruit: cheap land next to easy interconnects and new buildings designed to handle the weight of current panels. But as we ramp up solar, those things will run out. We need to utilize spaces and assets better. That’s what I think solar 2.0 will be: urban PV deployments, solar that’s closer to demand, and integrated into the built environment. These next-generation use cases aren’t just a racking system in the middle of nowhere.

    We’re going after commercial roofs, which would cover most [building] energy demand. Something like 80-90 percent of building electricity demands in the space can be met by rooftop solar.

    The goal is to do the manufacturing in-house. We use roll-to-roll manufacturing, so we can buy tons of equipment off the shelf, but most roll-to-roll manufacturing is made for things like labeling and tape, and not a semiconductor, so our plan is to be the core of semiconductor roll-to-roll manufacturing. There’s never been roll-to-roll semiconductor manufacturing before.

    Q: What have the last few months been like since you won the $100K competition?

    Bhakta: After winning the $100K, we’ve gotten a lot of inbound contact from MIT alumni. I think that’s my favorite part about the MIT community — people stay connected. They’ve been congratulating us, asking to chat, looking to partner, deploy, and invest.

    We’ve also gotten contacted by previous $100K competition winners and other startups that have spun out of MIT that are a year or two or three ahead of us in terms of development. There are a lot of startup scaling challenges that other startup founders are best equipped to answer, and it’s been huge to get guidance from them.

    We’ve also gotten into top accelerators like Cleantech Open, Venture For Climatetech, and ACCEL at Greentown Labs. We also onboarded two rockstar MIT Sloan interns for the summer. Now we’re getting to the product-development phase, building relationships with potential pilot partners, and scaling up the area of our technology.      

    Swartwout: Winning the $100K competition was a great point of validation for the company, because the judges themselves are well known in the venture capital community as well as people who have been in the startup ecosystem for a long time, so that has really propelled us forward. Ideally, we’ll be getting more MIT alumni to join us to fulfill this mission.

    Q: What are your plans for the next year or so?

    Swartwout: We’re planning on leveraging open-access facilities like those at MIT.nano and the University of Massachusetts Amherst. We’re pretty focused now on scaling size. Out of the lab, [the technology] is a 4-inch by 4-inch solar module, and the goal is to get up to something that’s relevant for the industry to offset electricity for building owners and generate electricity for the grid at a reasonable cost.

    Bhakta: In the next year, through those open-access facilities, the goal is to go from 100-millimeter width to 300-millimeter width and a very long length using a roll-to-roll manufacturing process. That means getting through the engineering challenges of scaling technology and fine tuning the performance.

    When we’re ready to deliver a pilotable product, it’s my job to have customers lined up ready to demonstrate this works on their buildings, sign longer term contracts to get early revenue, and have the support we need to demonstrate this at scale. That’s the goal. More

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    Powering the future in Mongolia

    Nestled within the Tuul River valley and embraced by the southern Khentii Mountain Range, Ulaanbaatar (UB), Mongolia’s largest city, presents itself as an arena where nature’s forces wage an unrelenting battle against human resilience. The capital city is an icy crucible, with bone-chilling winters that plummet temperatures to an astonishing -40 degrees Fahrenheit (-40 degrees Celsius). Mongolia, often hailed with the celestial moniker of “The Land of the Eternal Blue Sky,” paradoxically succumbs to a veil of pollution and energy struggles during the winter months, obscuring the true shade of the cherished vista.

    To understand the root of these issues, MIT students from classes 22.S094 (Climate and Sustainability Systems: Decarbonizing Ulaanbaatar at Scale) and 21A.S01 (Anthro-Engineering: Decarbonization at the Million-Person Scale) visited Mongolia to conduct on-site surveys, diving into the diverse tapestry of local life as they gleaned insight from various stakeholder groups. Setting foot on Mongolian soil on a crisp day in January, they wasted no time in shaking off the weariness of their arduous 17-hour flight, promptly embarking on a waiting bus. As they traversed the vast expanse of the countryside, their eyes were captivated by snow-laden terrain.

    That is, until a disconcerting sight unfolded — thick smog, akin to ethereal pillars, permeated the cityscape ahead. These imposing plumes emanated from the colossal smokestacks of Ulaanbaatar’s coal-fired power plants, steadfastly churning electricity and heat to fuel Mongolia’s central and district energy systems. Over 93 percent of the nation’s energy comes from coal-fired power plants, where the most considerable load is caused by household consumption. Nevertheless, with nearly half of Ulaanbaatar’s population disconnected from the central heating networks, one of Mongolia’s most significant sources of pollution comes from coal-burning stoves in the residential settlements known as the ger districts. Over the past three decades, since the democratic revolution in 1990, Mongolians have grappled with escalating concerns surrounding energy provision, accessibility, and sustainability.

    Engineers who think like anthropologists

    “We find ourselves compelled to venture on-site, engaging in direct conversations with the locals, and immersing ourselves in the fabric of daily life to uncover what we don’t know,” emphasized Michael Short, professor in MIT’s Department of Nuclear Science and Engineering and faculty lead of MIT’s NEET Climate and Sustainability Systems thread, shortly before heading to Mongolia.

    The Ulaanbaatar Project sprang from a multiyear collaboration between MIT and the National University of Mongolia (NUM). Shedding light on the matter, Professor Munkhbat Byambajav of the Department of Chemical and Biological Engineering at NUM underscored the paramount importance of mitigating environmental pollution at an economic scale to alleviate the heavy burden borne by the people.

    Class 22.S094 is offered through MIT’s New Engineering Education Transformation (NEET) program, which allows students with multidisciplinary interests to collaborate across departments within four different subject areas, or threads. In this capstone project, students consider ways to decarbonize a city like Ulaanbaatar, transitioning from burning coal briquettes to a more sustainable, energy-efficient solution, given several parameters and constraints set by the local context.

    One of the ideas students have recently explored is a thermal battery made with molten salt that can store enough energy to heat a ger for up to 12 hours with added insulation for cooling curve regulation. The Mongolian ger, meaning home, is a dome-like portable dwelling covered in felt and canvas, held together by ropes traditionally crafted of animal hair or wool. Over several semesters, students have been testing a version of their proposed idea on campus, working with a prototype that weighs around 35 pounds.

    Nathan Melenbrink, the lead instructor of NEET’s Climate and Sustainability Systems (CSS) thread, believes that the complexity of the Ulaanbaatar capstone project allows students to reject the one-way solution approach and instead consider challenges with a nonprescriptive mindset. The uniqueness of the CSS thread is that students are asked to build on the previous findings from the past cohort and iterate on their designs each year. This workflow has allowed the project to mature and advance in ways that may not be feasible within a semester schedule. When asked how the recent trip impacted the ongoing research back on campus, Melenbrink states, “In light of the recent trip to Mongolia, students are beginning to see the impact of cultural immersion and social awareness leveraging the technical scope and rigor of their work.”

    Course 21A.S01, taught by Professor Manduhai Buyandelger of the MIT Anthropology Section, proved instrumental in deepening students’ understanding of the intricate dynamics at play. She asks, “The prototype works in the lab, but does it work in real life once you factor in the challenges in the larger structures of delivery, production, and implementation in Mongolia?”

    This recognition of the social dimensions of engineering permeated the early stages of the UB project, engaging all participants, including students from MIT and NUM, professionals residing in Mongolia, and local nongovernmental organizations, fostering what Buyandelger aptly describes as “a collaboration on multiple scales: trans-disciplinary and transcontinental.” Lauren Bonilla, co-lecturer for the anthropology course, was crucial in devising the first onsite trip to Mongolia. Drawing upon her extensive ethnographic research in Mongolia that spans decades, Bonilla remarks, “To me, engineering is a highly social discipline.” She further stresses how anthro-engineering elevates the social dimensions of engineering by critically questioning the framing of problems and solutions, stating, “It draws on anthropological insights and methods, like ethnography, to bring a human face to the users of a technology and adds complexity and nuance to the social constraints that limit designs.”

    Making of khorkhog

    Amidst the frigid atmosphere, a traditional Mongolian ger stands in front of the Nuclear Science Laboratory at the National University of Mongolia, emitting warm steam from its roof. The faculty and students of NUM organize a welcoming event inside the ger, inviting everyone to partake in a khorkhog cookout. Earlier that week, a remark from the Mongolian energy representative stood out during one of the presentations: “We need powerful heat. Solar is not enough, and electricity is not enough. Mongolians need fire,” he had emphasized.

    Indeed, the culinary delight known as khorkhog demands the relentless embrace of scorching flames. The process involves a large metal jug, stones, fire, and lamb. With skillful precision, the volunteer chef places the fire-heated stones and large pieces of lamb into the cooking container, triggering a cascade of steam that fills the ger, accompanied by the sounds of sizzling and hissing. Everyone waits patiently as the cook carefully inspects the dish, keenly listening for signs of readiness. And when the time comes, a feast is shared among all, complemented by steam-cooked potatoes, freshly sliced onions, and vegetables. In this moment, the presence of fire symbolizes a profound connection with the heart of Mongolian culture, evoking a deep resonance among the gathered crowd as they partake in this cherished staple meal.

    The distance between two points

    Familiar faces form a grid on the computer screen as the standing meeting between the students in Massachusetts and Ulaanbaatar begins. Sharing the morning (evening in Mongolia) for updates has been a critical effort by both sides to stay engaged and make decisions together. NEET CSS students in Cambridge proceeded to share their latest findings.

    Lucy Nester, a nuclear science and engineering major, has been diligently working on developing a high-efficiency electrical heating solution for individual consumers. Her primary focus is leveraging the discounted electricity rates available in the ger districts and utilize existing infrastructure. Recognizing the importance of maximum flexibility in heating the brick, Nester emphasizes the “no one-size-fits-all” solution. She shares the results of her test trials, which involve both inductive and resistive heating methods, outlining the advantages and disadvantages of each approach. Despite her limited experience in electrical engineering and circuit building, Nester has impressively overcome the steep learning curve. She enthusiastically describes her UB trip as “one of the most remarkable experiences I’ve had during my time at MIT.”

    Darshdeep Grewal, a dedicated materials science and engineering major with a strong passion for data science and computation, has been diligently conducting research on convection heating using COMSOL Multiphysics. In his investigation, Grewal explores the correlation between air temperature and heating, investigates the impact of convecting air arrangement on the heating process, and examines the conditions that may contribute to overheating. Leveraging his expertise in computational workflows, Grewal presents an impressive collection of heatmap simulations derived from the extensive data accumulated by his team throughout the project. Recognizing the immense value of these simulations in modeling complex scenarios, he highlights the importance of running experiments concurrently with simulations to ensure accurate calibration of results, stating, “It’s important to stay rooted in reality.”

    Arina Khotimsky, another materials science and engineering major, has actively engaged in NEET’s Climate and Sustainability Systems thread since her sophomore year. Balancing the demands of her final semester at MIT and the upcoming review of 22.S094, Khotimsky reveals how she has seamlessly integrated her project involvement into her energy studies minor. Reflecting on her journey, she remarks, “Working on the Ulaanbaatar project has taught me the significance of taking local context into account while suggesting solutions as an engineer.” Khotimsky has been tirelessly iterating and refining the insulation box prototype, which holds the thermal battery and controls the rate at which the battery releases heat. In addition, the on-site observations have unveiled another design challenge — ensuring the insulation box functions as a secure and dependable means of transportation. 

    To “engineer” means to contrive through one’s deliberate use of skills. What confronted the UB Project team on site was not the limitations of skill or technology, but the real-world constraints often amiss in the early equation: the people and their everyday lives. With over 6,195 miles of distance between the two groups, it takes more than just dedication to make a collaboration blossom. That may be the desire for a positive impact. Moreover, it may be the goal of cultivating a healthier relationship with energy that spans a million-person scale. No matter where you are, there is no one solution to the complex story of energy. This progressive realization brings the two teams together every two weeks in virtual space, bridging the distance between the two points.  More

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    Arina Khotimsky ’23 awarded 2023 Michel David-Weill Scholarship

    Arina Khotimsky ’23 was selected for the 2023 Michel David-Weill scholarship, awarded each year to one student from the United States in a master’s program at Sciences Po in France who exemplifies the core values embodied by its namesake: excellence, leadership, multiculturalism, and high achievement. This fall Khotimsky will enter the master’s program in international energy, which is part of Sciences Po’s Paris School of International Affairs. The program aims to provide a holistic understanding of energy issues, across disciplines and across all energy sources.

    Khotimsky graduated this year from MIT with a major in materials science and engineering, and minors in energy studies and in French.

    Asked what drew her to her major, Khotimsky talked about her love of the outdoors. Seeing effects of climate change on the world around made her made her want to explore solutions. “I settled on material science and engineering because there’s so many different applications: whether it be solar power, developing different battery materials and chemistries, or some other technology. Getting that technical background at MIT can help me understand how we can implement solutions around the world, with diverse cultures in mind.”

    One of Khotimsky’s material sciences professors, Polina Anikeeva, observes that “Arina possesses the spirit of creativity, optimism, and unparalleled work ethic — all necessary ingredients to solve energy and climate challenges of our century.”

    Khotimsky is well aware of the big stakes in discussions around energy policy. She explains, “We have to cooperate internationally to make a dent in carbon emissions. The United States is historically the biggest CO2 emitter and has a large role to play to transition to a more sustainable future.”

    Her interest in studying climate change solutions on a world scale also converged with her interest in studying other languages and cultures. Her main language studies at MIT have been in French, although she also speaks Russian and beginner Chinese.

    Due to her achievement in MIT French classes, Khotimsky was one of nine students selected for a two-week cultural immersion program in Paris last June, led by MIT Professor Bruno Perreau. Perreau also had her in class last fall, and spoke about the energy and commitment she brought to class, describing her as “one of my very best students since I started to teach 22 years ago.” Khotimsky is excited to be living in France for her master’s program and putting her French skills to work.

    Khotimsky’s impressive undergraduate career has also included being co-president of the MIT Energy and Climate Club, and participating in the MIT delegation to 2022 Conference of the Parties summit (COP27) of the United Nations in Egypt last November. She also participated in the NEET Decarbonizing Ulaanbaatar project, traveling to Mongolia in Independent Activities Period 2023 with a group of students and instructors to work on clean heating technologies for traditional ger homes.

    In addition to her academic work and other extracurricular activities, Khotimsky was also a member of the MIT women’s rowing team. She walked onto the team as a first-year student, making it into the Varsity 8 boat for her senior season. Holly Metcalf, MIT women’s varsity openweight rowing coach, explains, “Being on the rowing team has in many ways become a metaphor for what Arina has come to study … She realized that rowing is about so much more than physics — it is about who one must become as an individual to contribute to the sum of mental and physical strength of the entire team.” Khotimsky was recognized on May 22 by the Patriot League, who named her the 2023 Patriot League Women’s Rowing Scholar-Athlete of the Year.

    Looking ahead, Khotimsky envisions her future involving international energy negotiations or policy. “The master’s degree I’m pursuing in international relations will help me develop skills to communicate with stakeholders from around the world and figure out how to implement solutions globally.” More

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    Embracing life’s surprises

    Experiments often yield unexpected results. In research and in life, MIT Associate Professor Cem Tasan has learned to embrace that uncertainty.

    “Very often we start with an idea or a hypothesis, and to test that idea we design experiments, and when we run the experiments, we see something totally different,” says Tasan, the newly tenured Thomas B. King Associate Professor of Metallurgy.

    Tasan has used those surprises to explore the boundaries of metallurgy and solid mechanics, gleaning new insights into how metals break and deform, and designing new kinds of damage-resistant alloys.

    “As they say, science is like taking a walk in the hills,” Tasan says. “You see the mountain far away, and that’s where you want to go, but as you head toward it, you see a beautiful flower on a different pathway, so you check that out. That happens so often to [my group]. It’s exciting.”

    Tasan has extended that approach to his career, leading him to take a faculty position at MIT despite not seeing the campus until his first job interview.

    “Being at MIT, or even in the USA, was never on my radar,” Tasan says. “It just wasn’t part of a plan.”

    That mindset has also helped him mentor students, whom he’s learned never to judge based on initial impressions.

    “I had a really bright student reach out and say ‘Everything is great, we have funding, we are productive, but I’m not sure I like what I’m doing,’” Tasan recalls. “We talked and identified another direction closer to the student’s interests, but that would mean we might not have secure funding or the necessary know-how, so there were all these disadvantages.

    “But we went down that road and it was amazing, because now this student was doing the research they really liked, and that successful student became an amazing student. Mentoring is complicated because on the outside things can seem fine, but the key idea is to pay attention to small details and keep communicating with these young people, who are on their own journeys. There’s no easy way other than communicating and observing.”

    A winding path

    Tasan grew up in Turkey and studied metallurgical and materials engineering at the country’s top college in the field, the Middle East Technical University.

    “What intrigued me about metallurgy is that it’s an engineering field, but it’s also strongly related with basic sciences,” Tasan says. “That connection exists in other engineering fields as well, but not as strongly. In materials science, it’s fair to say one leg is almost always in the fundamental side of things.”

    Tasan also travelled a lot as a young adult, backpacking with friends across Europe on a shoestring budget.

    “Early on, my personal goal in life was to move to Spain and eat tapas all the time and have fun,” Tasan jokes.

    During one such trip, Tasan packed a suit in the bottom of his backpack just in case he landed an interview with a graduate program. The preparation paid off in the Netherlands, where he met with members of the mechanical engineering department at the Eindhoven University of Technology. Tasan would go on to earn his PhD at the school, studying how damage and cracking takes place in metals.

    After earning his PhD in 2010, Tasan joined the Max Planck Institute for Iron Research in Germany, where he eventually led a research group that continued studying metal behavior and worked on creating new metal alloys that were more damage-resistant and had other unique properties.

    By 2015, Tasan was settled into a comfortable life in Germany. Then a position at MIT opened up.

    “At MIT, I could suddenly do much more on these topics that excited me, so my research could create a bigger impact,” Tasan says.

    After traveling to MIT for interviews, the talent and atmosphere also convinced Tasan to make the move.

    “I think it’s important to be surrounded by people who are very ambitious and who want to have a big impact,” Tasan says. “You walk in the Infinite Corridor, or any other MIT corridor, and every board you pass has stuff about people changing the world in a different way. Being in that environment inspires you.”

    Once in Cambridge, Tasan immediately loved what he describes as its “small-town feel,” comparing it to some European towns. He’s also embraced the Boston culture, becoming a fan of baseball and the Red Sox.

    Since arriving at MIT, Tasan’s group has studied metal samples’ response to stress and other stimuli in real time using a technique called in situ electron microscopy.

    “We do in situ tests, which means you take an electron microscope and basically build machines inside that allows you to take any metal and put it under different conditions, as you watch its structure evolve,” Tasan explains. “Because these experiments are so unique and complex, when a student designs an experiment and eventually brings the results back to me, it’s often the first-ever observation of some phenomena.”

    In 2020 Tasan’s group developed new in-situ methods for studying the effects of hydrogen in metals, leading to insights that could help with the transition to clean hydrogen energy. The approach has been adopted by other labs for further study.

    Tasan’s group also created a more damage resistant, high temperature alloy that’s part of a class of metals known as high entropy alloys. That work was published in the journal Nature Materials.

    “Doing physical metallurgy research allows us to connect basic understanding of metals and industrial applications,” Tasan says. “I’m dealing with atoms and how they interact — and at the same time I’m talking weekly with companies that produce thousands of tons of metals, and we’re using the same language. I can talk to a company producing steels for auto bodies or titanium for airplane engines, and the stuff I study in my lab is still valuable to them.”

    In one much-publicized Science paper, Tasan’s group uncovered the reasons why even the sharpest knives and razors dull after everyday processes like shaving.

    “We like to demonstrate the importance of materials science and metallurgy to a broader audience,” Tasan says. “The paper on why hair deforms steel was great because it was picked up in all kinds of news channels around the world, and it showed that even in very conventional areas, like making knives or blades, there’s a lot of new insights and paths to find.”

    Solving the ultimate puzzles

    Tasan brings the same careful diligence he uses to study metals to support students. He says he’s found that like metals, people also typically have more complex stories that you can only see if you look closely enough.

    “It’s interesting because everybody is so different,” Tasan says. “Once you start working with people and trying to help them, you see so many different dimensions that were not visible before. You have the opportunity to sit down with them and look them in the eye and try to understand what they really want. And it’s interesting because often they also don’t know what they want, and sometimes they even don’t know that they don’t know that!”

    Fortunately, Tasan enjoys those challenges most of all.

    “In a way, the researchers are puzzles waiting to be solved, like the research itself,” Tasan says. “And if you put in enough effort and you really care, you get this enormously gratifying feeling of helping someone succeed in life. It’s really a unique part of the job, and it’s what I love more than anything.” More

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    Even as temperatures rise, this hydrogel material keeps absorbing moisture

    The vast majority of absorbent materials will lose their ability to retain water as temperatures rise. This is why our skin starts to sweat and why plants dry out in the heat. Even materials that are designed to soak up moisture, such as the silica gel packs in consumer packaging, will lose their sponge-like properties as their environment heats up.

    But one material appears to uniquely resist heat’s drying effects. MIT engineers have now found that polyethylene glycol (PEG) — a hydrogel commonly used in cosmetic creams, industrial coatings, and pharmaceutical capsules — can absorb moisture from the atmosphere even as temperatures climb.

    The material doubles its water absorption as temperatures climb from 25 to 50 degrees Celsius (77 to 122 degrees Fahrenheit), the team reports.

    PEG’s resilience stems from a heat-triggering transformation. As its surroundings heat up, the hydrogel’s microstructure morphs from a crystal to a less organized “amorphous” phase, which enhances the material’s ability to capture water.

    Based on PEG’s unique properties, the team developed a model that can be used to engineer other heat-resistant, water-absorbing materials. The group envisions such materials could one day be made into devices that harvest moisture from the air for drinking water, particularly in arid desert regions. The materials could also be incorporated into heat pumps and air conditioners to more efficiently regulate temperature and humidity.

    “A huge amount of energy consumption in buildings is used for thermal regulation,” says Lenan Zhang, a research scientist in MIT’s Department of Mechanical Engineering. “This material could be a key component of passive climate-control systems.”

    Zhang and his colleagues detail their work in a study appearing today in Advanced Materials. MIT co-authors include Xinyue Liu, Bachir El Fil, Carlos Diaz-Marin, Yang Zhong, Xiangyu Li, and Evelyn Wang, along with Shaoting Lin of Michigan State University.

    Against intuition

    Evelyn Wang’s group in MIT’s Device Research Lab aims to address energy and water challenges through the design of new materials and devices that sustainably manage water and heat. The team discovered PEG’s unusual properties as they were assessing a slew of similar hydrogels for their water-harvesting abilities.

    “We were looking for a high-performance material that could capture water for different applications,” Zhang says. “Hydrogels are a perfect candidate, because they are mostly made of water and a polymer network. They can simultaneously expand as they absorb water, making them ideal for regulating humidity and water vapor.”

    The team analyzed a variety of hydrogels, including PEG, by placing each material on a scale that was set within a climate-controlled chamber. A material became heavier as it absorbed more moisture. By recording a material’s changing weight, the researchers could track its ability to absorb moisture as they tuned the chamber’s temperature and humidity.

    What they observed was typical of most materials: as the temperature increased, the hyrogels’ ability to capture moisture from the air decreased. The reason for this temperature-dependence is well-understood: With heat comes motion, and at higher temperatures, water molecules move faster and are therefore more difficult to contain in most materials.

    “Our intuition tells us that at higher temperatures, materials tend to lose their ability to capture water,” says co-author Xinyue Liu. “So, we were very surprised by PEG because it has this inverse relationship.”

    In fact, they found that PEG grew heavier and continued to absorb water as the researchers raised the chamber’s temperature from 25 to 50 degrees Celsius.

    “At first, we thought we had measured some errors, and thought this could not be possible,” Liu says. “After we double-checked everything was correct in the experiment, we realized this was really happening, and this is the only known material that shows increasing water absorbing ability with higher temperature.”

    A lucky catch

    The group zeroed in on PEG to try and identify the reason for its unusual, heat-resilient performance. They found that the material has a natural melting point at around 50 degrees Celsius, meaning that the hydrogel’s normally crystal-like microstructure completely breaks down and transforms into an amorphous phase. Zhang says that this melted, amorphous phase provides more opportunity for polymers in the material to grab hold of any fast-moving water molecules.

    “In the crystal phase, there might be only a few sites on a polymer available to attract water and bind,” Zhang says. “But in the amorphous phase, you might have many more sites available. So, the overall performance can increase with increased temperature.”

    The team then developed a theory to predict how hydrogels absorb water, and showed that the theory could also explain PEG’s unusual behavior if the researchers added a “missing term” to the theory. That missing term was the effect of phase transformation. They found that when they included this effect, the theory could predict PEG’s behavior, along with that of other temperature-limiting hydrogels.

    The discovery of PEG’s unique properties was in large part by chance. The material’s melting temperature just happens to be within the range where water is a liquid, enabling them to catch PEG’s phase transformation and its resulting super-soaking behavior. The other hydrogels happen to have melting temperatures that fall outside this range. But the researchers suspect that these materials are also capable of similar phase transformations once they hit their melting temperatures.

    “Other polymers could in theory exhibit this same behavior, if we can engineer their melting points within a selected temperature range,” says team member Shaoting Lin.

    Now that the group has worked out a theory, they plan to use it as a blueprint to design materials specifically for capturing water at higher temperatures.

    “We want to customize our design to make sure a material can absorb a relatively high amount of water, at low humidity and high temperatures,” Liu says. “Then it could be used for atmospheric water harvesting, to bring people potable water in hot, arid environments.”

    This research was supported, in part, by U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy. More

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    Scientists uncover the amazing way sandgrouse hold water in their feathers

    Many birds’ feathers are remarkably efficient at shedding water — so much so that “like water off a duck’s back” is a common expression. Much more unusual are the belly feathers of the sandgrouse, especially Namaqua sandgrouse, which absorb and retain water so efficiently the male birds can fly more than 20 kilometers from a distant watering hole back to the nest and still retain enough water in their feathers for the chicks to drink and sustain themselves in the searing deserts of Namibia, Botswana, and South Africa.

    How do those feathers work? While scientists had inferred a rough picture, it took the latest tools of microscopy, and patient work with a collection of sandgrouse feathers, to unlock the unique structural details that enable the feathers to hold water. The findings appear today in the Journal of the Royal Society Interface, in a paper by Lorna Gibson, the Matoula S. Salapatas Professor of Materials Science and Engineering and a professor of mechanical engineering at MIT, and Professor Jochen Mueller of Johns Hopkins University.

    The unique water-carrying ability of sandgrouse feathers was first reported back in 1896, Gibson says, by E.G.B. Meade-Waldo, who was breeding the birds in captivity. “He saw them behaving like this, and nobody believed him! I mean, it just sounded so outlandish,” Gibson says.

    In 1967, Tom Cade and Gordon MacLean reported detailed observations of the birds at watering holes, in a study that proved the unique behavior was indeed real. The scientists found that male sandgrouse feathers could hold about 25 milliliters of water, or about a tenth of a cup, after the bird had spent about five minutes dipping in the water and fluffing its feathers.

    About half of that amount can evaporate during the male bird’s half-hour-long flight back to the nest, where the chicks, which cannot fly for about their first month, drink the remainder straight from the feathers.

    Cade and MacLean “had part of the story,” Gibson says, but the tools didn’t exist at the time to carry out the detailed imaging of the feather structures that the new study was able to do.

    Gibson and Mueller carried out their study using scanning electron microscopy, micro-computed tomography, and video imaging. They borrowed Namaqua sandgrouse belly feathers from Harvard University’s Museum of Comparative Zoology, which has a collection of specimens of about 80 percent of the world’s birds.

    Bird feathers in general have a central shaft, from which smaller barbs extend, and then smaller barbules extend out from those. Sandgrouse feathers are structured differently, however. In the inner zone of the feather, the barbules have a helically coiled structure close to their base and then a straight extension. In the outer zone of the feather, the barbules lack the helical coil and are simply straight. Both parts lack the grooves and hooks that hold the vane of contour feathers together in most other birds.
    Video of water spreading through the specialized sandgrouse feathers, under magnification, shows the uncoiling and spreading of the feather’s barbules as they become wet. Initially, most barbules in the outer zone of the feather form tubular features.Credit: Specimen #142928, Museum of Comparative Zoology, Harvard University © President and Fellows of Harvard College.

    When wetted, the coiled portions of the barbules unwind and rotate to be perpendicular to the vane, producing a dense forest of fibers that can hold water through capillary action. At the same time, the barbules in the outer zone curl inward, helping to hold the water in.

    The microscopy techniques used in the new study allowed the dimensions of the different parts of the feather to be measured. In the inner zone, the barb shafts are large and stiff enough to provide a rigid base about which the other parts of the feather deform, and the barbules are small and flexible enough that surface tension is sufficient to bend the straight extensions into tear-like structures that hold water. And in the outer zone, the barb shafts and barbules are smaller still, allowing them to curl around the inner zone, further retaining water.

    While previous work had suggested that surface tension produced the water retention characteristics, “what we did was make measurements of the dimensions and do some calculations to show that that’s what is actually happening,” Gibson says. Her group’s work demonstrated that the varying stiffnesses of the different feather parts plays a key role in their ability to hold water.

    The study was mostly driven by intellectual curiosity about this unique behavioral phenomenon, Gibson says. “We just wanted to see how it works. The whole story just seemed so interesting.” But she says it might lead to some useful applications. For example, in desert regions where water is scarce but fog and dew regularly occur, such as in Chile’s Atacama Desert, some adaptation of this feather structure might be incorporated into the systems of huge nets that are used to collect water. “You could imagine this could be a way to improve those systems,” she says. “A material with this kind of structure might be more effective at fog harvesting and holding the water.”

    “This fascinating and in-depth study reveals how the different parts of the sandgrouse’s belly feathers — including the microscopic barb shafts and barbules — work together to hold water,” says Mary Caswell Stoddard, an evolutionary biologist at Princeton University, who was not associated with this study. “By using a suite of advanced imaging techniques to describe the belly feathers and estimate their bending stiffnesses, Mueller and Gibson add rich new details to our understanding of the sandgrouse’s water-carrying feathers. … This study may inspire others to take a closer look at diverse feather microstructures across bird species — and to wonder whether these structures, as in sandgrouse, help support unusual or surprising functions.”

    The work was partly supported by the National Science Foundation and the Matoula S. Salapatas Professorship in Materials Science and Engineering at MIT. More