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      in Energy

      Reflecting on COP28 — and humanity’s progress toward meeting global climate goals

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      With 85,000 delegates, the 2023 United Nations climate change conference, known as COP28, was the largest U.N. climate conference in history. It was held at the end of the hottest year in recorded history. And after 12 days of negotiations, from Nov. 30 to Dec. 12, it produced a decision that included, for the first time, language calling for “transitioning away from fossil fuels,” though it stopped short of calling for their complete phase-out.

      U.N. Climate Change Executive Secretary Simon Stiell said the outcome in Dubai, United Arab Emirates, COP28’s host city, signaled “the beginning of the end” of the fossil fuel era. 

      COP stands for “conference of the parties” to the U.N. Framework Convention on Climate Change, held this year for the 28th time. Through the negotiations — and the immense conference and expo that takes place alongside them — a delegation of faculty, students, and staff from MIT was in Dubai to observe the negotiations, present new climate technologies, speak on panels, network, and conduct research.

      On Jan. 17, the MIT Center for International Studies (CIS) hosted a panel discussion with MIT delegates who shared their reflections on the experience. Asking what’s going on at COP is “like saying, ‘What’s going on in the city of Boston today?’” quipped Evan Lieberman, the Total Professor of Political Science and Contemporary Africa, director of CIS, and faculty director of MIT International Science and Technology Initiatives (MISTI). “The value added that all of us can provide for the MIT community is [to share] what we saw firsthand and how we experienced it.” 

      Phase-out, phase down, transition away?

      In the first week of COP28, over 100 countries issued a joint statement that included a call for “the global phase out of unabated fossil fuels.” The question of whether the COP28 decision — dubbed the “UAE Consensus” — would include this phase-out language animated much of the discussion in the days and weeks leading up to COP28. 

      Ultimately, the decision called for “transitioning away from fossil fuels in energy systems, in a just, orderly and equitable manner.” It also called for “accelerating efforts towards the phase down of unabated coal power,” referring to the combustion of coal without efforts to capture and store its emissions.

      In Dubai to observe the negotiations, graduate student Alessandra Fabbri said she was “confronted” by the degree to which semantic differences could impose significant ramifications — for example, when negotiators referred to a “just transition,” or to “developed vs. developing nations” — particularly where evolution in recent scholarship has produced more nuanced understandings of the terms.

      COP28 also marked the conclusion of the first global stocktake, a core component of the 2015 Paris Agreement. The effort every five years to assess the world’s progress in responding to climate change is intended as a basis for encouraging countries to strengthen their climate goals over time, a process often referred to as the Paris Agreement’s “ratchet mechanism.” 

      The technical report of the first global stocktake, published in September 2023, found that while the world has taken actions that have reduced forecasts of future warming, they are not sufficient to meet the goals of the Paris Agreement, which aims to limit global average temperature increase to “well below” 2 degrees Celsius, while pursuing efforts to limit the increase to 1.5 degrees above pre-industrial levels.

      “Despite minor, punctual advancements in climate action, parties are far from being on track to meet the long-term goals of the Paris Agreement,” said Fabbri, a graduate student in the School of Architecture and Planning and a fellow in MIT’s Leventhal Center for Advanced Urbanism. Citing a number of persistent challenges, including some parties’ fears that rapid economic transition may create or exacerbate vulnerabilities, she added, “There is a noted lack of accountability among certain countries in adhering to their commitments and responsibilities under international climate agreements.” 

      Climate and trade

      COP28 was the first climate summit to formally acknowledge the importance of international trade by featuring an official “Trade Day” on Dec. 4. Internationally traded goods account for about a quarter of global greenhouse gas emissions, raising complex questions of accountability and concerns about offshoring of industrial manufacturing, a phenomenon known as “emissions leakage.” Addressing the nexus of climate and trade is therefore considered essential for successful decarbonization, and a growing number of countries are leveraging trade policies — such as carbon fees applied to imported goods — to secure climate benefits. 

      Members of the MIT delegation participated in several related activities, sharing research and informing decision-makers. Catherine Wolfram, professor of applied economics in the MIT Sloan School of Management, and Michael Mehling, deputy director of the MIT Center for Energy and Environmental Policy Research (CEEPR), presented options for international cooperation on such trade policies at side events, including ones hosted by the World Trade Organization and European Parliament. 

      “While COPs are often criticized for highlighting statements that don’t have any bite, they are also tremendous opportunities to get people from around the world who care about climate and think deeply about these issues in one place,” said Wolfram.

      Climate and health

      For the first time in the conference’s nearly 30-year history, COP28 included a thematic “Health Day” that featured talks on the relationship between climate and health. Researchers from MIT’s Abdul Latif Jameel Poverty Action Lab (J-PAL) have been testing policy solutions in this area for years through research funds such as the King Climate Action Initiative (K-CAI). 

      “An important but often-neglected area where climate action can lead to improved health is combating air pollution,” said Andre Zollinger, K-CAI’s senior policy manager. “COP28’s announcement on reducing methane leaks is an important step because action in this area could translate to relatively quick, cost-effective ways to curb climate change while improving air quality, especially for people living near these industrial sites.” K-CAI has an ongoing project in Colorado investigating the use of machine learning to predict leaks and improve the framework for regulating industrial methane emissions, Zollinger noted.

      This was J-PAL’s third time at COP, which Zollinger said typically presented an opportunity for researchers to share new findings and analysis with government partners, nongovernmental organizations, and companies. This year, he said, “We have [also] been working with negotiators in the [Middle East and North Africa] region in the months preceding COP to plug them into the latest evidence on water conservation, on energy access, on different challenging areas of adaptation that could be useful for them during the conference.”

      Sharing knowledge, learning from others

      MIT student Runako Gentles described COP28 as a “springboard” to greater impact. A senior from Jamaica studying civil and environmental engineering, Gentles said it was exciting to introduce himself as an MIT undergraduate to U.N. employees and Jamaican delegates in Dubai. “There’s a lot of talk on mitigation and cutting carbon emissions, but there needs to be much more going into climate adaptation, especially for small-island developing states like those in the Caribbean,” he said. “One of the things I can do, while I still try to finish my degree, is communicate — get the story out there to raise awareness.”

      At an official side event at COP28 hosted by MIT, Pennsylvania State University, and the American Geophysical Union, Maria T. Zuber, MIT’s vice president for research, stressed the importance of opportunities to share knowledge and learn from people around the world.

      “The reason this two-way learning is so important for us is simple: The ideas we come up with in a university setting, whether they’re technological or policy or any other kind of innovations — they only matter in the practical world if they can be put to good use and scaled up,” said Zuber. “And the only way we can know that our work has practical relevance for addressing climate is by working hand-in-hand with communities, industries, governments, and others.”

      Marcela Angel, research program director at the Environmental Solutions Initiative, and Sergey Paltsev, deputy director of MIT’s Joint Program on the Science and Policy of Global Change, also spoke at the event, which was moderated by Bethany Patten, director of policy and engagement for sustainability at the MIT Sloan School of Management.  More

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      in Environment

      Susan Solomon wins VinFuture Award for Female Innovators

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      Lee and Geraldine Martin Professor of Environmental Studies Susan Solomon has been awarded the 2023 VinFuture Award for Female Innovators. Solomon was picked out of almost 1,400 international nominations across four categories for “The discovery of the ozone depletion mechanism in Antarctica, contributing to the establishment of the Montreal Protocol.” The award, which comes with a $500,000 prize, highlights outstanding female researchers and innovators that can serve as role models for aspiring scientists.

      “I’m tremendously humbled by that, and I’ll do my best to live up to it,” says Solomon, who attended the ceremony in Hanoi, Vietnam, on Dec. 20.

      The VinFuture Awards are given annually to “honor scientific research and breakthrough technological innovations that can make a significant difference” according to their site. In addition to Female Innovators, the award has two other special categories, Innovators from Developing Countries and Innovators with Outstanding Achievements in Emerging Fields, as well as their overall grand prize. The awards have been given out by the Vietnam-based VinFuture Foundation since 2021.

      “Countries all around the world are part of scientific progress and innovation, and that a developing country is honoring that is really very lovely,” says Solomon, whose career as an atmospheric chemist has brought her onto the international stage and has shown her firsthand how important developing countries are in crafting global policy.

      In 1986 Solomon led an expedition of 16 scientists to Antarctica to measure the degradation of the ozone layer; she was the only woman on the team. She and her collaborators were able to figure out the atmospheric chemistry of chlorofluorocarbons and other similar chemicals that are now known as ozone-depleting substances. This work became foundational to the creation of the Montreal Protocol, an international agreement that banned damaging chemicals and has allowed the ozone to recover.

      Solomon joined the MIT faculty in 2012 and holds joint appointments in the departments of Chemistry and Earth, Atmospheric and Planetary Sciences. The success of the Montreal Protocol demonstrates the ability for international cooperation to enact effective environmental agreements; Solomon sees it as a blueprint for crafting further policy when it comes to addressing global climate change.

      “Women can do anything, even help save the ozone layer and solve other environmental problems,” she says. “Today’s problem of climate change is for all of us to be involved in solving.” More

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      in Environment

      New tool predicts flood risk from hurricanes in a warming climate

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      Coastal cities and communities will face more frequent major hurricanes with climate change in the coming years. To help prepare coastal cities against future storms, MIT scientists have developed a method to predict how much flooding a coastal community is likely to experience as hurricanes evolve over the next decades.

      When hurricanes make landfall, strong winds whip up salty ocean waters that generate storm surge in coastal regions. As the storms move over land, torrential rainfall can induce further flooding inland. When multiple flood sources such as storm surge and rainfall interact, they can compound a hurricane’s hazards, leading to significantly more flooding than would result from any one source alone. The new study introduces a physics-based method for predicting how the risk of such complex, compound flooding may evolve under a warming climate in coastal cities.

      One example of compound flooding’s impact is the aftermath from Hurricane Sandy in 2012. The storm made landfall on the East Coast of the United States as heavy winds whipped up a towering storm surge that combined with rainfall-driven flooding in some areas to cause historic and devastating floods across New York and New Jersey.

      In their study, the MIT team applied the new compound flood-modeling method to New York City to predict how climate change may influence the risk of compound flooding from Sandy-like hurricanes over the next decades.  

      They found that, in today’s climate, a Sandy-level compound flooding event will likely hit New York City every 150 years. By midcentury, a warmer climate will drive up the frequency of such flooding, to every 60 years. At the end of the century, destructive Sandy-like floods will deluge the city every 30 years — a fivefold increase compared to the present climate.

      “Long-term average damages from weather hazards are usually dominated by the rare, intense events like Hurricane Sandy,” says study co-author Kerry Emanuel, professor emeritus of atmospheric science at MIT. “It is important to get these right.”

      While these are sobering projections, the researchers hope the flood forecasts can help city planners prepare and protect against future disasters. “Our methodology equips coastal city authorities and policymakers with essential tools to conduct compound flooding risk assessments from hurricanes in coastal cities at a detailed, granular level, extending to each street or building, in both current and future decades,” says study author Ali Sarhadi, a postdoc in MIT’s Department of Earth, Atmospheric and Planetary Sciences.

      The team’s open-access study appears online today in the Bulletin of the American Meteorological Society. Co-authors include Raphaël Rousseau-Rizzi at MIT’s Lorenz Center, Kyle Mandli at Columbia University, Jeffrey Neal at the University of Bristol, Michael Wiper at the Charles III University of Madrid, and Monika Feldmann at the Swiss Federal Institute of Technology Lausanne.

      The seeds of floods

      To forecast a region’s flood risk, weather modelers typically look to the past. Historical records contain measurements of previous hurricanes’ wind speeds, rainfall, and spatial extent, which scientists use to predict where and how much flooding may occur with coming storms. But Sarhadi believes that the limitations and brevity of these historical records are insufficient for predicting future hurricanes’ risks.

      “Even if we had lengthy historical records, they wouldn’t be a good guide for future risks because of climate change,” he says. “Climate change is changing the structural characteristics, frequency, intensity, and movement of hurricanes, and we cannot rely on the past.”

      Sarhadi and his colleagues instead looked to predict a region’s risk of hurricane flooding in a changing climate using a physics-based risk assessment methodology. They first paired simulations of hurricane activity with coupled ocean and atmospheric models over time. With the hurricane simulations, developed originally by Emanuel, the researchers virtually scatter tens of thousands of “seeds” of hurricanes into a simulated climate. Most seeds dissipate, while a few grow into category-level storms, depending on the conditions of the ocean and atmosphere.

      When the team drives these hurricane simulations with climate models of ocean and atmospheric conditions under certain global temperature projections, they can see how hurricanes change, for instance in terms of intensity, frequency, and size, under past, current, and future climate conditions.

      The team then sought to precisely predict the level and degree of compound flooding from future hurricanes in coastal cities. The researchers first used rainfall models to simulate rain intensity for a large number of simulated hurricanes, then applied numerical models to hydraulically translate that rainfall intensity into flooding on the ground during landfalling of hurricanes, given information about a region such as its surface and topography characteristics. They also simulated the same hurricanes’ storm surges, using hydrodynamic models to translate hurricanes’ maximum wind speed and sea level pressure into surge height in coastal areas. The simulation further assessed the propagation of ocean waters into coastal areas, causing coastal flooding.

      Then, the team developed a numerical hydrodynamic model to predict how two sources of hurricane-induced flooding, such as storm surge and rain-driven flooding, would simultaneously interact through time and space, as simulated hurricanes make landfall in coastal regions such as New York City, in both current and future climates.  

      “There’s a complex, nonlinear hydrodynamic interaction between saltwater surge-driven flooding and freshwater rainfall-driven flooding, that forms compound flooding that a lot of existing methods ignore,” Sarhadi says. “As a result, they underestimate the risk of compound flooding.”

      Amplified risk

      With their flood-forecasting method in place, the team applied it to a specific test case: New York City. They used the multipronged method to predict the city’s risk of compound flooding from hurricanes, and more specifically from Sandy-like hurricanes, in present and future climates. Their simulations showed that the city’s odds of experiencing Sandy-like flooding will increase significantly over the next decades as the climate warms, from once every 150 years in the current climate, to every 60 years by 2050, and every 30 years by 2099.

      Interestingly, they found that much of this increase in risk has less to do with how hurricanes themselves will change with warming climates, but with how sea levels will increase around the world.

      “In future decades, we will experience sea level rise in coastal areas, and we also incorporated that effect into our models to see how much that would increase the risk of compound flooding,” Sarhadi explains. “And in fact, we see sea level rise is playing a major role in amplifying the risk of compound flooding from hurricanes in New York City.”

      The team’s methodology can be applied to any coastal city to assess the risk of compound flooding from hurricanes and extratropical storms. With this approach, Sarhadi hopes decision-makers can make informed decisions regarding the implementation of adaptive measures, such as reinforcing coastal defenses to enhance infrastructure and community resilience.

      “Another aspect highlighting the urgency of our research is the projected 25 percent increase in coastal populations by midcentury, leading to heightened exposure to damaging storms,” Sarhadi says. “Additionally, we have trillions of dollars in assets situated in coastal flood-prone areas, necessitating proactive strategies to reduce damages from compound flooding from hurricanes under a warming climate.”

      This research was supported, in part, by Homesite Insurance. More

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      in Energy

      Cobalt-free batteries could power cars of the future

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      Many electric vehicles are powered by batteries that contain cobalt — a metal that carries high financial, environmental, and social costs.

      MIT researchers have now designed a battery material that could offer a more sustainable way to power electric cars. The new lithium-ion battery includes a cathode based on organic materials, instead of cobalt or nickel (another metal often used in lithium-ion batteries).

      In a new study, the researchers showed that this material, which could be produced at much lower cost than cobalt-containing batteries, can conduct electricity at similar rates as cobalt batteries. The new battery also has comparable storage capacity and can be charged up faster than cobalt batteries, the researchers report.

      “I think this material could have a big impact because it works really well,” says Mircea Dincă, the W.M. Keck Professor of Energy at MIT. “It is already competitive with incumbent technologies, and it can save a lot of the cost and pain and environmental issues related to mining the metals that currently go into batteries.”

      Dincă is the senior author of the study, which appears today in the journal ACS Central Science. Tianyang Chen PhD ’23 and Harish Banda, a former MIT postdoc, are the lead authors of the paper. Other authors include Jiande Wang, an MIT postdoc; Julius Oppenheim, an MIT graduate student; and Alessandro Franceschi, a research fellow at the University of Bologna.

      Alternatives to cobalt

      Most electric cars are powered by lithium-ion batteries, a type of battery that is recharged when lithium ions flow from a positively charged electrode, called a cathode, to a negatively electrode, called an anode. In most lithium-ion batteries, the cathode contains cobalt, a metal that offers high stability and energy density.

      However, cobalt has significant downsides. A scarce metal, its price can fluctuate dramatically, and much of the world’s cobalt deposits are located in politically unstable countries. Cobalt extraction creates hazardous working conditions and generates toxic waste that contaminates land, air, and water surrounding the mines.

      “Cobalt batteries can store a lot of energy, and they have all of features that people care about in terms of performance, but they have the issue of not being widely available, and the cost fluctuates broadly with commodity prices. And, as you transition to a much higher proportion of electrified vehicles in the consumer market, it’s certainly going to get more expensive,” Dincă says.

      Because of the many drawbacks to cobalt, a great deal of research has gone into trying to develop alternative battery materials. One such material is lithium-iron-phosphate (LFP), which some car manufacturers are beginning to use in electric vehicles. Although still practically useful, LFP has only about half the energy density of cobalt and nickel batteries.

      Another appealing option are organic materials, but so far most of these materials have not been able to match the conductivity, storage capacity, and lifetime of cobalt-containing batteries. Because of their low conductivity, such materials typically need to be mixed with binders such as polymers, which help them maintain a conductive network. These binders, which make up at least 50 percent of the overall material, bring down the battery’s storage capacity.

      About six years ago, Dincă’s lab began working on a project, funded by Lamborghini, to develop an organic battery that could be used to power electric cars. While working on porous materials that were partly organic and partly inorganic, Dincă and his students realized that a fully organic material they had made appeared that it might be a strong conductor.

      This material consists of many layers of TAQ (bis-tetraaminobenzoquinone), an organic small molecule that contains three fused hexagonal rings. These layers can extend outward in every direction, forming a structure similar to graphite. Within the molecules are chemical groups called quinones, which are the electron reservoirs, and amines, which help the material to form strong hydrogen bonds.

      Those hydrogen bonds make the material highly stable and also very insoluble. That insolubility is important because it prevents the material from dissolving into the battery electrolyte, as some organic battery materials do, thereby extending its lifetime.

      “One of the main methods of degradation for organic materials is that they simply dissolve into the battery electrolyte and cross over to the other side of the battery, essentially creating a short circuit. If you make the material completely insoluble, that process doesn’t happen, so we can go to over 2,000 charge cycles with minimal degradation,” Dincă says.

      Strong performance

      Tests of this material showed that its conductivity and storage capacity were comparable to that of traditional cobalt-containing batteries. Also, batteries with a TAQ cathode can be charged and discharged faster than existing batteries, which could speed up the charging rate for electric vehicles.

      To stabilize the organic material and increase its ability to adhere to the battery’s current collector, which is made of copper or aluminum, the researchers added filler materials such as cellulose and rubber. These fillers make up less than one-tenth of the overall cathode composite, so they don’t significantly reduce the battery’s storage capacity.

      These fillers also extend the lifetime of the battery cathode by preventing it from cracking when lithium ions flow into the cathode as the battery charges.

      The primary materials needed to manufacture this type of cathode are a quinone precursor and an amine precursor, which are already commercially available and produced in large quantities as commodity chemicals. The researchers estimate that the material cost of assembling these organic batteries could be about one-third to one-half the cost of cobalt batteries.

      Lamborghini has licensed the patent on the technology. Dincă’s lab plans to continue developing alternative battery materials and is exploring possible replacement of lithium with sodium or magnesium, which are cheaper and more abundant than lithium. More

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      in Environment

      K. Lisa Yang Global Engineering and Research Center will prioritize innovations for resource-constrained communities

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      Billions of people worldwide face threats to their livelihood, health, and well-being due to poverty. These problems persist because solutions offered in developed countries often do not meet the requirements — related to factors like price, performance, usability, robustness, and culture — of poor or developing countries. Academic labs frequently try to tackle these challenges, but often to no avail because they lack real-world, on-the-ground knowledge from key stakeholders, and because they do not have an efficient, reliable means of converting breakthroughs to real-world impact.

      The new K. Lisa Yang Global Engineering and Research (GEAR) Center at MIT, founded with a $28 million gift from philanthropist and investor Lisa Yang, aims to rethink how products and technologies for resource-constrained communities are conceived, designed, and commercialized. A collaboration between MIT’s School of Engineering and School of Science, the Yang GEAR Center will bring together a multidisciplinary team of MIT researchers to assess today’s most pressing global challenges in three critical areas: global health, climate change mitigation and adaptation, and the water-energy-food nexus.

      “As she has shown over and over through her philanthropy, Lisa Yang shares MIT’s passion for connecting fundamental research and real-world data to create positive impact,” says MIT president Sally Kornbluth. “I’m grateful for her powerful vision and incredible generosity in founding the K. Lisa Yang GEAR Center. I can’t imagine a better use of MIT’s talents than working to improve the lives and health of people around the world.”

      Yang’s gift expands her exceptional philanthropic support of human health and basic science research at MIT over the past six years. Yang GEAR Center will join MIT’s Yang Tan Collective, an assemblage of six major research centers focused on accelerating collaboration in basic science, research, and engineering to realize translational strategies that improve human health and well-being at a global scale.

      “Billions of people face daily life-or-death challenges that could be improved with elegant technologies,” says Yang. “And yet I’ve learned how many products and tools created by top engineers don’t make it out of the lab. They may look like clever ideas during the prototype phase, but they are entirely ill-suited to the communities they were designed for. I am very excited about the potential of a deliberate and thoughtful engineering effort that will prioritize the design of technologies for use in impoverished communities.”

      Cost, material availability, cultural suitability, and other market mismatches hinder many major innovations in global health, food, and water from being translated to use in resource-constrained communities. Yang GEAR Center will support a major research and design program with its mission to strategically identify compelling challenges and associated scientific knowledge gaps in resource-constrained communities then address them through academic innovation to create and translate transformative technologies.

      The center will be led by Amos Winter, associate professor of mechanical engineering, whose lab focuses on creating technologies that marry innovative, low-cost design with an in-depth understanding of the unique socioeconomic constraints of emerging markets.

      “Academia has a key role to play in solving the historically unsolvable challenges in resource-constrained communities,” says Winter. “However, academic research is often disconnected from the real-world requirements that must be satisfied to make meaningful change. Yang GEAR Center will be a catalyst for innovation to impact by helping colleagues identify compelling problems and focus their talents on realizing real-world solutions, and by providing mechanisms for commercial dissemination. I am extremely grateful to find in Lisa a partner who shares a vision for how academic research can play a more efficient and targeted role in addressing the needs of the world’s most disadvantaged populations.”

      The backbone of the Yang GEAR Center will be a team of seasoned research scientists and engineers. These individuals will scout real-world problems and distill the relevant research questions then help assemble collaborative teams. As projects develop, center staff will mentor students, build and conduct field pilots, and foster relationships with stakeholders around the world. They will be strategically positioned to translate technology at the end of projects through licensing and startups. Center staff and collaborators will focus on creating products and services for climate-driven migrants, such as solar-powered energy and water networks; technologies for reducing atmospheric carbon and promoting the hydrogen economy; brackish water desalination and irrigation solutions; and high-performance, global health diagnostics and devices.

      For instance, a Yang GEAR Center team focused on creating water-saving and solar-powered irrigation solutions for farmers in the Middle East and North Africa will continue its work in the region. They will conduct exploratory research; build a team of stakeholders, including farmers, agricultural outreach organizations, irrigation hardware manufacturers, retailers, water and agriculture scientists, and local government officials; design, rigorously test, and iterate prototypes both in the lab and in the field; and conduct large-scale field trials to garner user feedback and pave the way to product commercialization.

      “Grounded in foundational scientific research and blended with excellence in the humanities, MIT provides a framework that integrates people, economics, research, and innovation. By incorporating multiple perspectives — and being attentive to the needs and cultures of the people who will ultimately rely on research outcomes — MIT can have the greatest impact in areas of health, climate science, and resource security,” says Nergis Mavalvala, dean of the School of Science and the Curtis and Kathleen Marble Professor of Astrophysics.

      An overarching aim for the center will be to educate graduates who are global engineers, designers, and researchers positioned for a career of addressing compelling, high-impact challenges. The center includes four endowed Hock E. Tan GEAR Center Fellowships that will support graduate students and/or postdoctoral fellows eager to enter the field of global engineering. The fellowships are named for MIT alumnus and Broadcom CEO Hock E. Tan ’75 SM ’75.

      “I am thrilled that the Yang GEAR Center is taking a leading role in training problem-solvers who will rethink how products and inventions can help communities facing the most pressing challenges of our time,” adds Anantha Chandrakasan, dean of the School of Engineering and the Vannevar Bush Professor of Electrical Engineering and Computer Science. “These talented young students,  postdocs, and staff have the potential to reach across disciplines — and across the globe — to truly transform the impact engineering can have in the future.” More

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      in Energy

      Soaring high, in the Army and the lab

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      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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      in Energy

      Study reveals a reaction at the heart of many renewable energy technologies

      by

      A key chemical reaction — in which the movement of protons between the surface of an electrode and an electrolyte drives an electric current — is a critical step in many energy technologies, including fuel cells and the electrolyzers used to produce hydrogen gas.

      For the first time, MIT chemists have mapped out in detail how these proton-coupled electron transfers happen at an electrode surface. Their results could help researchers design more efficient fuel cells, batteries, or other energy technologies.

      “Our advance in this paper was studying and understanding the nature of how these electrons and protons couple at a surface site, which is relevant for catalytic reactions that are important in the context of energy conversion devices or catalytic reactions,” says Yogesh Surendranath, a professor of chemistry and chemical engineering at MIT and the senior author of the study.

      Among their findings, the researchers were able to trace exactly how changes in the pH of the electrolyte solution surrounding an electrode affect the rate of proton motion and electron flow within the electrode.

      MIT graduate student Noah Lewis is the lead author of the paper, which appears today in Nature Chemistry. Ryan Bisbey, a former MIT postdoc; Karl Westendorff, an MIT graduate student; and Alexander Soudackov, a research scientist at Yale University, are also authors of the paper.

      Passing protons

      Proton-coupled electron transfer occurs when a molecule, often water or an acid, transfers a proton to another molecule or to an electrode surface, which stimulates the proton acceptor to also take up an electron. This kind of reaction has been harnessed for many energy applications.

      “These proton-coupled electron transfer reactions are ubiquitous. They are often key steps in catalytic mechanisms, and are particularly important for energy conversion processes such as hydrogen generation or fuel cell catalysis,” Surendranath says.

      In a hydrogen-generating electrolyzer, this approach is used to remove protons from water and add electrons to the protons to form hydrogen gas. In a fuel cell, electricity is generated when protons and electrons are removed from hydrogen gas and added to oxygen to form water.

      Proton-coupled electron transfer is common in many other types of chemical reactions, for example, carbon dioxide reduction (the conversion of carbon dioxide into chemical fuels by adding electrons and protons). Scientists have learned a great deal about how these reactions occur when the proton acceptors are molecules, because they can precisely control the structure of each molecule and observe how electrons and protons pass between them. However, when proton-coupled electron transfer occurs at the surface of an electrode, the process is much more difficult to study because electrode surfaces are usually very heterogenous, with many different sites that a proton could potentially bind to.

      To overcome that obstacle, the MIT team developed a way to design electrode surfaces that gives them much more precise control over the composition of the electrode surface. Their electrodes consist of sheets of graphene with organic, ring-containing compounds attached to the surface. At the end of each of these organic molecules is a negatively charged oxygen ion that can accept protons from the surrounding solution, which causes an electron to flow from the circuit into the graphitic surface.

      “We can create an electrode that doesn’t consist of a wide diversity of sites but is a uniform array of a single type of very well-defined sites that can each bind a proton with the same affinity,” Surendranath says. “Since we have these very well-defined sites, what this allowed us to do was really unravel the kinetics of these processes.”

      Using this system, the researchers were able to measure the flow of electrical current to the electrodes, which allowed them to calculate the rate of proton transfer to the oxygen ion at the surface at equilibrium — the state when the rates of proton donation to the surface and proton transfer back to solution from the surface are equal. They found that the pH of the surrounding solution has a significant effect on this rate: The highest rates occurred at the extreme ends of the pH scale — pH 0, the most acidic, and pH 14, the most basic.

      To explain these results, researchers developed a model based on two possible reactions that can occur at the electrode. In the first, hydronium ions (H3O+), which are in high concentration in strongly acidic solutions, deliver protons to the surface oxygen ions, generating water. In the second, water delivers protons to the surface oxygen ions, generating hydroxide ions (OH-), which are in high concentration in strongly basic solutions.

      However, the rate at pH 0 is about four times faster than the rate at pH 14, in part because hydronium gives up protons at a faster rate than water.

      A reaction to reconsider

      The researchers also discovered, to their surprise, that the two reactions have equal rates not at neutral pH 7, where hydronium and hydroxide concentrations are equal, but at pH 10, where the concentration of hydroxide ions is 1 million times that of hydronium. The model suggests this is because the forward reaction involving proton donation from hydronium or water contributes more to the overall rate than the backward reaction involving proton removal by water or hydroxide.

      Existing models of how these reactions occur at electrode surfaces assume that the forward and backward reactions contribute equally to the overall rate, so the new findings suggest that those models may need to be reconsidered, the researchers say.

      “That’s the default assumption, that the forward and reverse reactions contribute equally to the reaction rate,” Surendranath says. “Our finding is really eye-opening because it means that the assumption that people are using to analyze everything from fuel cell catalysis to hydrogen evolution may be something we need to revisit.”

      The researchers are now using their experimental setup to study how adding different types of ions to the electrolyte solution surrounding the electrode may speed up or slow down the rate of proton-coupled electron flow.

      “With our system, we know that our sites are constant and not affecting each other, so we can read out what the change in the solution is doing to the reaction at the surface,” Lewis says.

      The research was funded by the U.S. Department of Energy Office of Basic Energy Sciences. More

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      in Security

      Food for thought

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      MIT graduate student Juana De La O describes herself as a food-motivated organism, so it’s no surprise that she reaches for food and baking analogies when she’s discussing her thesis work in the lab of undergraduate officer and professor of biology Adam Martin. 

      Consider the formative stages of a croissant, she offers, occasionally providing homemade croissants to accompany the presentation: When one is forming the puff pastry, the dough is folded over the butter again and again. Tissues in a developing mouse embryo must similarly fold and bend, creating layers and structures that become the spine, head, and organs — but these tissues have no hands to induce those formative movements. 

      De La O is studying neural tube closure, the formation of the structure that becomes the spinal cord and the brain. Disorders like anencephaly and craniorachischisis occur when the head region fails to close in a developing fetus. It’s a heartbreaking defect, De La O says, because it’s 100 percent lethal — but the fetus fully develops otherwise. 

      “Your entire central nervous system hinges on this one event happening successfully,” she says. “On the fundamental level, we have a very limited understanding of the mechanisms required for neural closure to happen at all, much less an understanding of what goes wrong that leads to those defects.” 

      Hypothetically speaking

      De La O hails from Chicago, where she received an undergraduate degree from the University of Chicago and worked in the lab of Ilaria Rebay. De La O’s sister was the first person in her family to go to and graduate from college — De La O, in turn, is the first person in her family to pursue a PhD. 

      From her first time visiting campus, De La O could see MIT would provide a thrilling environment in which to study.

      “MIT was one of the few places where the students weren’t constantly complaining about how hard their life was,” she says. “At lunch with prospective students, they’d be talking to each other and then just organically slip into conversations about science.”

      The department emails acceptance letters and sends a physical copy via snail mail. De La O’s letter included a handwritten note from department head Amy Keating, then a graduate officer, who had interviewed De La O during her campus visit. 

      “That’s what really sold it for me,” she recalls. “I went to my PI [principal investigator]’s office and said, ‘I have new data’” and I showed her the letter, and there was lots of unintelligible crying.” 

      To prepare her for graduate school, her parents, both immigrants from Mexico, spent the summer teaching De La O to make all her favorite dishes because “comfort food feels like home.”   

      When she reached MIT, however, the Covid-19 pandemic ground the world to a halt and severely limited what students could experience during rotations. Far from home and living alone, De La O taught herself to bake, creating the confections she craved but couldn’t leave her apartment to purchase. De La O didn’t get to work as extensively as she would have liked during her rotation in the Martin lab. 

      Martin had recently returned from a sabbatical that was spent learning a new research model; historically a fly lab, Martin was planning to delve into mouse research. 

      “My final presentation was, ‘Here’s a hypothetical project I would hypothetically do if I were hypothetically going to work with mice in a fly lab,’” De La O says. 

      Martin recalls being impressed. De La O is skilled at talking about science in an earnest and engaging way, and she dug deep into the literature and identified points Martin hadn’t considered. 

      “This is a level of independence that I look for in a student because it is important to the science to have someone who is contributing their ideas and independent reading and research to a project,” Martin says. 

      After agreeing to join the lab — news she shared with Martin via a meme — she got to work. 

      Charting mouse development

      The neural tube forms from a flat sheet whose sides rise and meet to create a hollow cylinder. De La O has observed patterns of actin and myosin changing in space and time as the embryo develops. Actin and myosin are fibrous proteins that provide structure in eukaryotic cells. They are responsible for some cell movement, like muscle contraction or cell division. Fibers of actin and myosin can also connect across cells, forming vast networks that coordinate the movements of whole tissues. By looking at the structure of these networks, researchers can make predictions about how force is affecting those tissues.

      De La O has found indications of a difference in the tension across the tissue during the critical stages of neural tube closure, which contributes to the tissue’s ability to fold and form a tube. They are not the first research group to propose this, she notes, but they’re suggesting that the patterns of tension are not uniform during a single stage of development.

      “My project, on a really fundamental level, is an atlas for a really early stage of mouse development for actin and myosin,” De La O says. “This dataset doesn’t exist in the field yet.” 

      However, De La O has been performing analyses exclusively in fixed samples, so she may be quantifying phenomena that are not actually how tissues behave. To determine whether that’s the case, De La O plans to analyze live samples.

      The idea is that if one could carefully cut tissue and observe how quickly it recoils, like slicing through a taught rubber band, those measurements could be used to approximate force across the tissue. However, the techniques required are still being developed, and the greater Boston area currently lacks the equipment and expertise needed to attempt those experiments. 

      A big part of her work in the lab has been figuring out how to collect and analyze relevant data. This research has already taken her far and wide, both literally and virtually. 

      “We’ve found that people have been very generous with their time and expertise,” De La O says. “One of the benefits we, as fly people, brought into this field is we don’t know anything — so we’re going to question everything.”

      De La O traveled to the University of Virginia to learn live imaging techniques from associate professor of cell biology Ann Sutherland, and she’s also been in contact with Gabriel Galea at University College London, where Martin and De La O are considering a visit for further training. 

      “There are a lot of reasons why these experiments could go wrong, and one of them is that I’m not trained yet,” she says. “Once you know how to do things on an optimal setup, you can figure out how to make it work on a less-optimal setup.”

      Collaboration and community

      De La O has now expanded her cooking repertoire far beyond her family’s recipes and shares her new creations when she visits home. At MIT, she hosts dinner parties, including one where everything from the savory appetizers to the sweet desserts contained honey, thanks to an Independent Activities Period course about the producers of the sticky substance, and she made and tried apple pie for the first time with her fellow graduate students after an afternoon of apple picking. 

      De La O says she’s still learning how to say no to taking on additional work outside of her regular obligations as a PhD student; she’s found there’s a lot of pressure for underrepresented students to be at the forefront of diversity efforts, and although she finds that work extremely fulfilling, she can, and has, stretched herself too thin in the past. 

      “Every time I see an application that asks ‘How will you work to increase diversity,’ my strongest instinct is just to write ‘I’m brown and around — you’re welcome,’” she jokes. “The greatest amount of diversity work I will do is to get where I’m going. Me achieving my goals increases diversity inherently, but I also want to do well because I know if I do, I will make everything better for people coming after me.”

      De La O is confident her path will be in academia, and troubleshooting, building up protocols, and setting up standards for her work in the Martin Lab has been “an excellent part of my training program.” 

      De La O and Martin embarked on a new project in a new model for the lab for De La O’s thesis, so much of her graduate studies will be spent laying the groundwork for future research. 

      “I hope her travels open Juana’s eyes to science being a larger community and to teach her about how to lead a collaboration,” Martin says. “Overall, I think this project is excellent for a student with aspirations to be a PI. I benefited from extremely open-ended projects as a student and see, in retrospect, how they prepared me for my work today.” More