Evelyn Reynolds

MIT engineers have discovered a new way of generating electricity using tiny carbon particles that can create a current simply by interacting with liquid surrounding them.

The liquid, an organic solvent, draws electrons out of the particles, generating a current that could be used to drive chemical reactions or to power micro- or nanoscale robots, the researchers say.

“This mechanism is new, and this way of generating energy is completely new,” says Michael Strano, the Carbon P. Dubbs Professor of Chemical Engineering at MIT. “This technology is intriguing because all you have to do is flow a solvent through a bed of these particles. This allows you to do electrochemistry, but with no wires.”

In a new study describing this phenomenon, the researchers showed that they could use this electric current to drive a reaction known as alcohol oxidation — an organic chemical reaction that is important in the chemical industry.

Strano is the senior author of the paper, which appears today in Nature Communications. The lead authors of the study are MIT graduate student Albert Tianxiang Liu and former MIT researcher Yuichiro Kunai. Other authors include former graduate student Anton Cottrill, postdocs Amir Kaplan and Hyunah Kim, graduate student Ge Zhang, and recent MIT graduates Rafid Mollah and Yannick Eatmon.

Unique properties

The new discovery grew out of Strano’s research on carbon nanotubes — hollow tubes made of a lattice of carbon atoms, which have unique electrical properties. In 2010, Strano demonstrated, for the first time, that carbon nanotubes can generate “thermopower waves.” When a carbon nanotube is coated with layer of fuel, moving pulses of heat, or thermopower waves, travel along the tube, creating an electrical current.

That work led Strano and his students to uncover a related feature of carbon nanotubes. They found that when part of a nanotube is coated with a Teflon-like polymer, it creates an asymmetry that makes it possible for electrons to flow from the coated to the uncoated part of the tube, generating an electrical current. Those electrons can be drawn out by submerging the particles in a solvent that is hungry for electrons.

To harness this special capability, the researchers created electricity-generating particles by grinding up carbon nanotubes and forming them into a sheet of paper-like material. One side of each sheet was coated with a Teflon-like polymer, and the researchers then cut out small particles, which can be any shape or size. For this study, they made particles that were 250 microns by 250 microns.

When these particles are submerged in an organic solvent such as acetonitrile, the solvent adheres to the uncoated surface of the particles and begins pulling electrons out of them.

“The solvent takes electrons away, and the system tries to equilibrate by moving electrons,” Strano says. “There’s no sophisticated battery chemistry inside. It’s just a particle and you put it into solvent and it starts generating an electric field.”

“This research cleverly shows how to extract the ubiquitous (and often unnoticed) electric energy stored in an electronic material for on-site electrochemical synthesis,” says Jun Yao, an assistant professor of electrical and computer engineering at the University of Massachusetts at Amherst, who was not involved in the study. “The beauty is that it points to a generic methodology that can be readily expanded to the use of different materials and applications in different synthetic systems.”

Particle power

The current version of the particles can generate about 0.7 volts of electricity per particle. In this study, the researchers also showed that they can form arrays of hundreds of particles in a small test tube. This “packed bed” reactor generates enough energy to power a chemical reaction called an alcohol oxidation, in which an alcohol is converted to an aldehyde or a ketone. Usually, this reaction is not performed using electrochemistry because it would require too much external current.

“Because the packed bed reactor is compact, it has more flexibility in terms of applications than a large electrochemical reactor,” Zhang says. “The particles can be made very small, and they don’t require any external wires in order to drive the electrochemical reaction.”

In future work, Strano hopes to use this kind of energy generation to build polymers using only carbon dioxide as a starting material. In a related project, he has already created polymers that can regenerate themselves using carbon dioxide as a building material, in a process powered by solar energy. This work is inspired by carbon fixation, the set of chemical reactions that plants use to build sugars from carbon dioxide, using energy from the sun.

In the longer term, this approach could also be used to power micro- or nanoscale robots. Strano’s lab has already begun building robots at that scale, which could one day be used as diagnostic or environmental sensors. The idea of being able to scavenge energy from the environment to power these kinds of robots is appealing, he says.

“It means you don’t have to put the energy storage on board,” he says. “What we like about this mechanism is that you can take the energy, at least in part, from the environment.”

The research was funded by the U.S. Department of Energy and a seed grant from the MIT Energy Initiative. More

The year 2030 serves as the resolution to the United Nation’s Agenda for Sustainable Development. The agenda, adopted in 2015 by all UN member states including the United States, mobilizes global efforts to protect the planet, end poverty, foster peace, and safeguard the rights of all people. Nine years out from the target date, the sustainable development goals of the agenda still remain ambitious, and as relevant as ever.

MIT Lincoln Laboratory has been growing its efforts to provide technology solutions in support of such goals. “We need to discuss innovative ways that advanced technology can address some of these most pressing humanitarian, climate, and health challenges,” says Jon Pitts, who leads Lincoln Laboratory’s Humanitarian Assistance and Disaster Relief Systems Group.

To help foster these discussions, Pitts and Mischa Shattuck, who serves as the senior humanitarian advisor at Lincoln Laboratory, recently launched a new lecture series, called the Future of Humanitarian Technology.

In the inaugural session on April 28, Lincoln Laboratory researchers presented three topics inherently linked to each other — those of climate change, disaster response, and global health. The webinar was free and open to the public.

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The Future of Humanitarian Technology: MIT Lincoln Laboratory hosted a seminar exploring climate change, disaster response, and global health technology and how these areas might look ten years from now.

Accelerating sustainable technology

Deb Campbell, a senior staff member in the HADR Systems Group, started the session with a discussion of how to accelerate the national and global response to climate change.

“Because the timeline is so short and challenges so complex, it is essential to make good, evidence-based decisions on how to get to where we need to go,” she said. “We call this approach systems analysis and architecture, and by taking this approach we can create a national climate change resilience roadmap.”

This roadmap implements more of what we already know how to do, for example utilizing wind and solar energy, and identifies gaps where research and development are needed to reach specific goals. One example is the transition to a fully zero-emission vehicle (ZEV) fleet in the United States in the coming decades; California has already directed that all of the state’s new car sales be ZEV by 2035. Systems analysis indicates that achieving this “fleet turnover” will require improved electric grid infrastructure, more charging stations, batteries with higher capacity and faster charging, and greener fuels as the transition is made from combustion engines.

Campbell also stressed the importance of using regional proving grounds to accelerate the transition of new technologies across the country and globe. These proving grounds refer to areas where climate-related prototypes can be evaluated under the pressures of real-world conditions. For example, the Northeast has older, stressed energy infrastructure that needs upgrading to meet future demand, and is the most natural place to begin implementing and testing new systems. The Southwest, which faces water shortages, can test technologies for even more efficient use of water resources and ways to harvest water from air. Today, Campbell and her team are conducting a study to investigate a regional proving ground concept in Massachusetts.

“We will need to continuously asses technology development and drive investments to meet these aggressive timelines,” Campbell added.

Improving disaster response

The United States experiences more natural disasters than any other country in the world and has spent $800 billion in last 10 years on recovery, which on average takes seven years.

“At the core of disaster support is information,” said Chad Council, also a researcher in the HADR Systems Group. “Knowing where impacts are and the severity of those impact drives decisions on the quantity and type of support. This can lay the ground work for a successful recovery … We know that the current approach is too slow and costly for years to come.”

By 2030, Council contends that the government could save lives and reduce costs by leveraging a national remote sensing platform for disaster response. It would use an open architecture that integrates advanced sensor data, field data, modeling, and analytics driven by artificial intelligence to deliver critical information in a standard way to emergency managers across the country. This platform could allow for highly accurate virtual site inspections, wide area search-and-rescue, determination of road damage at city-wide scales, and debris quantifications.

“To be clear, there’s no one-size-fits-all sensor platform. Some systems are good for a large-scale disaster, but for a small disaster, it might be faster for local transportation department to fly a small drone to image damage,” Council said. “The key is if this national platform is developed to produce the same data as local governments are used to, then this platform will be familiar and trustworthy when that level of disaster response is needed.”

Over the next two years, the team plans to continue to work with the Federal Emergency Management Agency, the U.S. National Guard, national laboratories, and academia on this open architecture. In parallel, a prototype remote sensing asset will be shared across state and local governments to gain enthusiasm and trust. According to Council, a national remote sensing strategy for disaster response could be employed by the end of 2029.

Predicting disease outbreaks

Kajal Claypool, a senior staff member in the Biological and Chemical Technologies Group, concluded with a discussion on using artificial intelligence to predict and mitigate the spread of disease.

She asks us to fast-forward nine years, and imagine we have convergence of three global health disasters: a new variant of Covid-30 spreading across globe, vector-borne diseases spreading in central and south America, and the first carrier with Ebola has flown into Atlanta. “Well, what if we were able to bring together data from existing surveillance systems, social media, environmental conditions, weather, political unrest, and migration, and use AI analytics to predict an outbreak down to a geolocation, and that first carrier never gets on the airplane?” she asked. “None of these are a far stretch.”

Artificial intelligence has been used to tackle some of these ideas, but the solutions are one-offs and siloed, Claypool said. One of the greatest impediments to using AI tools to solve global health challenges is harmonizing data, the process of bringing together data of varying semantics and file formats and transforming it into one cohesive dataset.

“We believe the right solution is to build a federated, open, and secure data platform where data can be shared across stakeholders and nations without loss of control at the nation, state, or stakeholder level,” Claypool said. “These siloes must be broken down and capabilities available for low- and middle-income nations.”

Over next few years, the laboratory team aims to develop this global health AI platform, building it one disease and one region as a time. The proof of concept will start with malaria, which kills 1.2 million people annually. While there are a number of interventions available today to fight malaria outbreaks, including vaccines, Claypool said that the prediction of hot spots and the decision support needed to intervene is essential. The next major milestone would be to provide data-driven diagnostics and interventions across the globe for other disease conditions.

“It’s an ambitious but achievable vision. It needs the right partnerships, trust, and vision to make this a reality, and reduce transmission of disease and save lives globally,” she said.

Addressing humanitarian challenges is a growing R&D focus at Lincoln Laboratory. Last fall, the organization established a new research division, Biotechnology and Human Systems, to further explore global issues around climate change, health, and humanitarian assistance. 

“Our goal is to build collaboration and communication with a broader community around all of these topics. They are all terribly important and complex and require significant global effort to make a difference,” Pitts says.

The next event in this series will take place in September. More

Improved computing power and an exponential increase in data have helped fuel the rapid rise of artificial intelligence. But as AI systems become more sophisticated, they’ll need even more computational power to address their needs, which traditional computing hardware most likely won’t be able to keep up with. To solve the problem, MIT spinout Lightelligence is developing the next generation of computing hardware.

The Lightelligence solution makes use of the silicon fabrication platform used for traditional semiconductor chips, but in a novel way. Rather than building chips that use electricity to carry out computations, Lightelligence develops components powered by light that are low energy and fast, and they might just be the hardware we need to power the AI revolution. Compared to traditional architectures, the optical chips made by Lightelligence offer orders of magnitude improvement in terms of high speed, low latency, and low power consumption.

In order to perform arithmetic operations, electronic chips need to combine tens, sometimes hundreds, of logic gates. To perform this process requires the electronic chip transistors to switch off and on for multiple clock periods. Every time a logic gate transistor switches, it generates heat and consumes power.

Not so with the chips produced by Lightelligence. In the optical domain, arithmetic computations are done with physics instead of with logic gate transistors that require multiple clocks. More clocks means a slower time to get a result. “We precisely control how the photons interact with each other inside the chip,” says Yichen Shen PhD ’16, co-founder and CEO of Lightelligence. “It’s just light propagating through the chip, photons interfering with each other. The nature of the interference does the mathematics that we want it to do.”

This process of interference generates very little heat, which means Shen’s optical computing chips enable much lower power consumption than their electron-powered counterparts. Shen points out that we’ve made use of fiber optics for long-distance communication for decades. “Think of the optical fibers spread across the bottom of the Pacific Ocean, and the light propagating through thousands of kilometers without losing much power. Lightelligence is bringing this concept for long-distance communication to on-chip compute.”

With most forecasters projecting an end to Moore’s Law sometime in 2025, Shen believes his optic-driven solution is poised to address many of the computational challenges of the future. “We’re changing the fundamental way computing is done, and I think we’re doing it at the right time in history,” says Shen. “We believe optics is going to be the next computing platform, at least for linear operations like AI.”

To be clear, Shen does not envision optics replacing the entire electronic computing industry. Rather, Lightelligence aims to accelerate certain linear algebra operations to perform quick, power-efficient tasks like those found in artificial neural networks.

Much of AI compute happens in the cloud at data centers like the ones supporting Amazon or Microsoft. Because AI algorithms are computationally intensive, AI compute takes up a large percentage of data center capacity. Picture tens of thousands of servers, running continuously, burning millions of dollars worth of electricity. Now imagine replacing some of those conventional servers with Lightelligence servers that burn much less power at a fraction of the cost. “Our optical chips would greatly reduce the cost of data centers, or, put another way, greatly increase the computational capability of those data centers for AI applications,” says Shen.  

And what about self-driving vehicles? They rely on cameras and AI computation to make quick decisions. But a conventional digital electronic chip doesn’t “think” quickly enough to make the decisions necessary at high speeds. Faster computational imaging leads to faster decision-making. “Our chip completes these decision-making tasks at a fraction of the time of regular chips, which would enable the AI system within the car to make much quicker decisions and more precise decisions, enabling safer driving,” says Shen.

Lightelligence boasts an all-MIT founding team, supported by 40 technical experts, including machine learning pioneers, leading photonic researchers, and semiconductor industry veterans intent on revolutionizing computing technology. Shen did his PhD work in the Department of Physics with professors Marin Soljajic and John Joannoupolos, where he developed an interest in the intersection of photonics and AI. “I realized that computation is a key enabler of modern artificial intelligence, and faster computing hardware would be needed to complement the growth of faster, smarter AI algorithms,” he says.

Lightelligence was founded in 2017 when Shen teamed up with Soljajic and two other MIT alumni. Fellow co-founder Huaiyu Meng SM ’14, PhD ’18 received his doctorate in electrical engineering and now serves as Lightelligence’s vice president of photonics. Rounding out the founding team is Spencer Powers MBA ’16. Powers, who received his MBA from MIT Sloan School of Management, is also a Lightelligence board member with extensive experience in the startup world.

Shen and his team are not alone in this new field of optical computing, but they do have key advantages over their competitors. First off, they invented the technology at the Institute. Lightelligence is also the first company to have built a complete system of optical computing hardware, which it accomplished in April 2019. Shen is self-assured in the innovation potential of Lightelligence and what it could mean for the future, regardless of the competition. “There are new stories of teams working in this space, but we’re not only the first, we’re the fastest in terms of execution. I stand by that,” he says.

But there’s another reason Shen’s not worried about the competition. He likens this stage in the evolution of the technology to the era when transistors were replacing vacuum tubes. Several transistor companies were making the leap, but they weren’t competing with each other so much as they were innovating to compete with the incumbent industry. “Having more competitors doing optical computing is good for us at this stage,” says Shen. “It makes for a louder voice, a bigger community to expand and enhance the whole ecosystem for optical computing.”

By 2021, Shen anticipates that Lightelligence will have de-risked 80-90 percent of the technical challenges necessary for optical computing to be a viable commercial product. In the meantime, Lightelligence is making the most of its status as the newest member of the MIT Startup Exchange accelerator, STEX25, building deep relationships with tier-one customers on several niche applications where there is a pressing need for high-performance hardware, such as data centers and manufacturers. More

Growing up, Awele Uwagwu’s view of energy was deeply influenced by the oil and gas industry. He was born and raised in Port Harcourt, a city on the southern coast of Nigeria, and his hometown shaped his initial interest in understanding the role of energy in our lives.

“I basically grew up in a city colored by oil and gas,” says Uwagwu. “Many of the jobs in that area are in the oil sector, and I saw a lot of large companies coming in and creating new buildings and infrastructure. That very much tailored my interest in the energy sector. I kept thinking: What is all of this stuff going on, and what are all these big machines that I see every day? The more sinister side of it was: Why is the water bad? Why is the air bad? And, what can I do about it?”

Uwagwu has shaped much of his educational and professional journey around answering that question: “What can I do about it?” He is now a senior at MIT, majoring in chemical engineering with a minor in energy studies.

After attending high school in Nigeria’s capital city, Abuja, Uwagwu decided to pursue a degree in chemical engineering and briefly attended the University of Illinois at Urbana-Champaign in 2016. Unfortunately, the impacts of a global crash in oil prices made the situation difficult back in Nigeria, so he returned home and found employment at an oil services company working on a water purification process.

It was during this time that he decided to apply to MIT. “I wanted to go to a really great place,” he says, “and I wanted to take my chances.” After only a few months of working at his new job, he was accepted to MIT.

“At this point in my life I had a much clearer picture of what I wanted to do. I knew I wanted to be in the energy sector and make some sort of impact. But I didn’t quite know how I was going to do that,” he says.

With this in mind, Uwagwu met with Rachel Shulman, the undergraduate academic coordinator at the MIT Energy Initiative, to learn about the different ways that MIT is engaged in energy. He eventually decided to become an energy studies minor and concentrate in energy engineering studies through the 10-ENG: Energy program in the Department of Chemical Engineering. Additionally, he participated in the Undergraduate Research Opportunities Program (UROP) in the lab of William H. Green, the Hoyt C. Hottel Professor in Chemical Engineering, focusing on understanding the different reaction pathways for the production of soot from the combustion of carbon.

After this engaging experience, he reconnected with Shulman to get involved with another UROP, this time with a strong focus in renewable energy. She pointed him toward Ian Mathews — a postdoc in the Photovoltaic Research Laboratory and founder of Sensai Analytics — to discuss ways he could make a beneficial impact on the energy industry in Nigeria. This conversation led to a second UROP, under the supervision of Mathews. In that project, Uwagwu worked to figure out how cost-effective solar energy would be in Nigeria compared to petrol-powered generators, which are commonly used to supplement the unreliable national grid.

“The idea we had is that these generators are really, really bad for the environment, whereas solar is cheap and better for the environment,” Uwagwu says. “But we needed to know if solar is actually affordable.” After setting up a software model and connecting with Leke Oyefeso, a friend back home, to get data on generators, they concluded that solar was cost-comparable and often cheaper than the generators.

Armed with this information and another completed UROP, Uwagwu thought, “What happens next?” Quickly an idea started forming, so he and Oyefeso went to Venture Mentoring Services at MIT to figure out how to leverage this knowledge to start a company that could deliver a unique and much-needed product to the Nigerian market.

They ran through many different potential business plans and ideas, eventually deciding on creating software to design solar systems that are tailored to Nigeria’s specific needs and context. Having come up with the initial idea, they “chatted with people on the solar scene back home to see if this is even useful or if they even need this.”

Through these discussions and market research, it became increasingly clear to them what sort of novel and pivotal product they could offer to help accelerate Nigeria’s burgeoning solar sector, and their initial idea took on a new shape: solar design software coupled with an online marketplace that connects solar providers to funding sources and energy consumers. In recognition of his unique venture, Uwagwu received a prestigious Legatum Fellowship, a program that offers entrepreneurial MIT students strong mentoring and networking opportunities, educational experiences, and substantial financial support.

Since its founding in the summer of 2020, their startup, Idagba, has been hard at work getting its product ready for market. Starting a company in the midst of Covid-19 has created a set of unique challenges for Uwagwu and his team, especially as they operate on a whole other continent from their target market.

“We wanted to travel to Lagos last summer but were unable to do so,” he says. “We can’t make the software without talking to the people and businesses who are going to use it, so there are a lot of Zoom and phone calls going on.”

In spite of these challenges, Idagba is well on its path to commercialization. “Currently we are developing our minimum viable product,” comments Uwagwu. “The software is going to be very affordable, so there’s very little barrier for entry. We really want to help create this market for solar.”

In some ways, Idagba is drawing lessons from the success of Mo Ibrahim and his mobile phone company, Celtel. In the late 1990s, Celtel was able to quickly and drastically lower the overall price of cell phones across many countries in Africa, allowing for the widespread adoption of mobile communication at a much faster pace than had been anticipated. To Uwagwu, this same idea can be replicated for solar markets. “We want to reduce the financial and technical barriers to entry for solar like he did for telecom.”

This won’t be easy, but Uwagwu is up to the task. He sees his company taking off in three phases. The first is getting the design software online. After that has been accomplished — by mid-2021 — comes the hard part: getting customers and solar businesses connected and using the program. Once they have an existing user base and proven cash flow, the ultimate goal of the company is to create and facilitate an ecosystem of people wanting to push solar energy forward. This will make Idagba, as Uwagwu puts it, “the hub of solar energy in Nigeria.” Idagba has a long way to go before reaching that point, but Uwagwu is confident that the building blocks are in place to ensure its success.

After graduating in June, Uwagwu will be taking up a full-time position at the prestigious consulting firm Bain and Company, where he plans to gain even more experience and connections to help grow his company. This opportunity will provide him with the knowledge and expertise to come back to Idagba and, as he says, “commit my life to this.”

“This idea may seem ambitious and slightly nonsensical right now,” says Uwagwu, “but this venture has the potential to significantly push Nigeria away from unsustainable fossil fuel consumption to a much cleaner path.” More

Matthew Johnston was a physics senior looking to postpone his entry into adulting. He had an intense four years at MIT; when he wasn’t in class, he was playing baseball and working various tech development gigs.

Johnston had led the MIT Engineers baseball team to a conference championship, becoming the first player in his team’s history to be named a three-time Google Cloud Academic All-American. He put an exclamation mark on his career by hitting four home runs in his final game. 

Johnston also developed a novel method of producing solar devices as a researcher with GridEdge Solar at MIT, and worked on a tax-loss harvesting research project as an intern at Impact Labs in San Francisco, California. As he contemplated post-graduation life, he liked the idea of gaining new experiences before committing to a company.

Remotely Down Under

MISTI-Australia matched him with an internship at Sydney-based Okra Solar, which manufactures smart solar charge controllers in Shenzhen, China, to help power off-the-grid remote villages in Southeast Asian countries such as Cambodia and the Philippines, as well as in Nigeria. 

“I felt that I had so much more to learn before committing to a full-time job, and I wanted to see the world,” he says. “Working an internship for Okra in Sydney seemed like it would be the perfect buffer between university life and life in the real world. If all went well, maybe I would end up living in Sydney a while longer.”

After graduating in May 2020 with a BS in physics, a minor in computer science, and a concentration in philosophy, he prepared to live in Sydney, with the possibility of travel to Shenzhen, when he received a familiar pitch: a curveball. 

Like everyone else, he had hoped that the pandemic would wind down before his Down Under move, but when that didn’t happen, he pivoted to sharing a place with friends in Southern California, where they could hike and camp in nearby Sequoia National Park when they weren’t working remotely.

On Okra’s software team, he focused on data science to streamline the maintenance and improve the reliability of Okra’s solar energy systems. However, his remote status didn’t mesh with an ongoing project to identify remote villages without grid access. So, he launched his own data project: designing a model to identify shaded solar panels based on their daily power output. That project was placed on hold until they could get more reliable data, but he gained experience setting up machine-learning problems as he developed a pipeline to retrieve, process, and load the data to train the model.

“This project helped me understand that most of the effort in a data science problem goes into sourcing and processing the data. Unfortunately, it seemed that it was just a bit too early for the model to perform accurately.”

Team-powered engine

Coordinating with a team of 23 people from more than 10 unique cultures, scattered across 11 countries in different time zones, presented yet another challenge. He responded by developing a productive workflow by leaving questions in his code reviews that would be answered by the next morning.

“Working remotely is ultimately a bigger barrier to team cohesion than productivity,” he says. He overcame that hurdle as well; the Aussie team took a liking to him and nicknamed him Jonno. “They’re an awesome group to be around and aren’t afraid to laugh at themselves.”   

Soon, Jonno was helping the service delivery team efficiently diagnose and resolve real issues in the field using sensor data. By automating the maintenance process in this way, Okra makes it possible for energy companies to deploy and manage last-mile energy projects at scale. Several months later, when he began contributing to the firmware team, he also took on the project of calculating a battery’s state of charge, with the goal to open-source a robust and reliable algorithm.

“Matt excelled despite the circumstance,” says Okra Solar co-founder and CEO Afnan Hannan. “Matt contributed to developing Okra’s automated field alerts system that monitors the health and performance of Okra’s solar systems, which are deployed across Southeast Asia and Africa. Additionally, Matt led the development of a state-of-the-art Kalman filter-based online state-of-charge (SoC) algorithm. This included research, prototyping, developing back-testing infrastructure, and finally implementing and deploying the solution on Okra’s microcontroller. An accurate and stable SoC has been a vital part of Okra’s cutting-edge Battery Sharing feature, for which we have Matt to thank.” 

Full power

After six months, Johnston joined Okra full time in January, moving to Phnom Penh, Cambodia, to join some of the team in person and immerse himself into firmware and data science. In the short term, the goal is to electrify villages to provide access to much cheaper and more accessible energy.

“Previously, the only way many of these villages could access electricity was by charging a car battery using a diesel generator,” he says. “This process is very expensive, and it is impossible to charge many batteries simultaneously. In contrast, Okra provides, cheap, accessible, and renewable energy for the entire village.”

For Johnston to see an Okra project firsthand, some villages are a 30-minute boat ride from their nearest town. He and others travel there to demonstrate small appliances that many in the world take for granted, such as using an electric blender to make a smoothie.

“It’s really amazing to see how hard-to-reach these villages are and how much electricity can help them,” says Johnston. “Something as simple as using a rice cooker instead of a wood fire can save a family countless hours of chopping wood. It also helps us think about how we can improve our product, both for the users and the energy companies.”   

“In the long term, the vision is that by providing electricity, we can introduce the possibility of online education and more productive uses of power, allowing these communities to join the modern economy.”

While getting to Phnom Penh was a challenge, he credits MIT for hitting yet another home run.

“I think two of the biggest things I learned from both baseball and physics were how to learn challenging things and how to overcome failure. It takes persistence to keep digging for more information and practicing what you’ve already failed, and this same way of thinking has helped me to develop my professional skills. At the same time, I am grateful for the time I spent studying philosophy. Thinking deeply about what might lead to a meaningful life for myself and for others has led me to stumble upon opportunities like this one.” More

Batteries and fuel cells often rely on a process known as ion diffusion to function. In ion diffusion, ionized atoms move through solid materials, similar to the process of water being absorbed by rice when cooked. Just like cooking rice, ion diffusion is incredibly temperature-dependent and requires high temperatures to happen fast.

This temperature dependence can be limiting, as the materials used in some systems like fuel cells need to withstand high temperatures sometimes in excess of 1,000 degrees Celsius. In a new study, a team of researchers at MIT and the University of Muenster in Germany showed a new effect, where ion diffusion is enhanced while the material remains cold, by only exciting a select number of vibrations known as phonons. This new approach — which the team refers to as “phonon catalysis” — could lead to an entirely new field of research. Their work was published in Cell Reports Physical Science.

In the study, the research team used a computational model to determine which vibrations actually caused ions to move during ion diffusion. Rather than increasing the temperature of the entire material, they increased the temperature of just those specific vibrations in a process they refer to as targeted phonon excitation.

“We only heated up the vibrations that matter, and in doing so we were able to show that you could keep the material cold, but have it behave just like it’s very hot,” says Asegun Henry, professor of mechanical engineering and co-author of the study.

This ability to keep materials cool during ion diffusion could have a wide range of applications. In the example of fuel cells, if the entire cell doesn’t need to be exposed to extremely high temperatures engineers could use cheaper materials to build them. This would lower the cost of fuel cells and would help them last longer — solving the issue of the short lifetime of many fuel cells.

The process could also have implications for lithium-ion batteries.

“Discovering new ion conductors is critical to advance lithium batteries, and opportunities include enabling the use of lithium metal, which can potentially double the energy of lithium-ion batteries. Unfortunately, the fundamental understanding of ion conduction is lacking,” adds Yang Shao-Horn, W.M. Keck Professor of Energy and co-author.

This new work builds upon her previous research, specifically the work of Sokseiha Muy PhD ’18 on design principles for ion conductors, which shows lowering phonon energy in structures reduces the barrier for ion diffusion and potentially increases ion conductivity. Kiarash Gordiz, a postdoc working jointly with Henry’s Atomistic Simulation and Energy Research Group and Shao-Horn’s Electrochemical Energy Laboratory, wondered if they could combine Shao-Horn’s research on ion conduction with Henry’s research on heat transfer.

“Using Professor Shao-Horn’s previous work on ion conductors as a starting point, we set out to determine exactly which phonon modes are contributing to ion diffusion,” says Gordiz.

Henry, Gordiz, and their team used a model for lithium phosphate, which is often found in lithium-ion batteries. Using a computational method known as normal mode analysis, along with nudged elastic-band calculations and molecular dynamics simulations, the research group quantitatively computed how much each phonon contributes to the ion diffusion process in lithium phosphate.

Armed with this knowledge, researchers could use lasers to selectively excite or heat up specific phonons, rather than exposing the entire material to high temperatures. This method could open up a new world of possibilities.

The dawn of a new field

Henry believes this method could lead to the creation of a new research field — one he refers to as “phonon catalysis.” While the new work focuses specifically on ion diffusion, Henry sees applications in chemical reactions, phase transformations, and other temperature-dependent phenomena.

“Our group is fascinated by the idea that you may be able to catalyze all kinds of things now that we have the technique to figure out which phonons matter,” says Henry. “All of these reactions that usually require extreme temperatures could now happen at room temperature.”

Henry and his team have begun exploring potential applications for phonon catalysis. Gordiz has been looking at using the method for lithium superionic conductors, which could be used in clean energy storage. The team is also considering applications such as a room-temperature superconductor and even the creation of diamonds, which require extremely high pressure and temperatures that could be triggered at much lower temperatures through phonon catalysis.

“This idea of selective excitation, focusing only on the parts that you need rather than everything, could be a very big kind of paradigm shift for how we operate things,” says Henry. “We need to start thinking of temperature as a spectrum and not just a single number.”

The researchers plan to show more examples of targeted phonon excitation working in different materials. Moving forward, they hope to demonstrate their computational model works experimentally in these materials.  More

Caroline White-Nockleby is a PhD student in MIT’s doctoral program in History, Anthropology, and Science, Technology, and Society (HASTS), which is co-sponsored by the History and Anthropology sections, and the Program in Science, Technology and Society (STS). White-Nockleby’s research centers on the shifting supply chains of renewable energy infrastructures. In particular, she is interested in the interfaces between policymaking, social dynamics, and tech innovations in the sourcing, manufacture, and implementation of energy storage technologies. She received a BA in geosciences and American studies from Williams College and an MPhil in social anthropology from the University of Cambridge, England. MIT SHASS Communications spoke with her for the series Solving Climate: Humanistic Perspectives from MIT about the perspectives her field and research bring to addressing the climate crisis.  Q: How has research from the HASTS doctoral program shaped your understanding of global climate change and its myriad ecological and social impacts?A: MIT HASTS alum Candis Callison [PhD ’10], now an anthropologist and professor of journalism, wrote her first book, “How Climate Change Comes to Matter” about the different discursive frameworks — what she terms “vernaculars” — through which scientists, journalists, Indigenous communities, sustainable investment firms, and evangelical Christian environmental organizations understand climate change.Through ethnographic research, Callison shows that although these understandings were grounded in a shared set of facts, each drew from different cultural and ethical frameworks. These variations could silo conversations, even as they illustrated the pluralities of the climate crisis by highlighting different challenges and compelling different actions.

HASTS faculty member and environmental historian Megan Black, an associate professor in the MIT History Section, is currently researching the history of the first Landsat satellites launched in the 1970s. The technical capacities of Landsat’s visualization mechanisms were influenced by the political context of the Cold War. Black’s investigation has revealed, among other findings, that Landsat’s imaging devices were particularly well-suited to surfacing geological features and thus to minerals exploration, which was a key application of Landsat data in its inaugural decade. The historical context of the satellite’s initial design has thus shaped — and limited — the information accessible to the many investigations that today use early Landsat imagery as a vital indicator of decadal-scale environmental changes. 

Climate change is not only a scientific and technological matter, but also a social, political, and historical one. It stems from centuries of uneven geographies of energy extraction and distribution; related historical and geographical processes today distribute climate vulnerabilities unevenly across places and people.The dimensions of today’s promising interventions have, in turn, been configured by past funding and research agendas — and the many technologies employed have a wide variety of implications for equity, ethics, and justice. The parameters of public opinion and policy debate on the nature and risks of climate change, as well as its conceivable solutions, are similarly shaped by socio-historical contexts.MIT’s Program in History, Anthropology, Science, Technology and Society (HASTS) supports research that attends to the social and historical facets of climate change. Just as importantly, the HASTS program equips scholars with the tools to develop nuanced understandings of the scientific and technological mechanisms of its causes, impacts, and proposed solutions. Such technical and social attunement makes the program well-situated — perhaps particularly so — to unravel the myriad social and ecological dimensions of the climate crisis.

Q: Technology offers hope for addressing climate change, and it also presents challenges. The renewable energy industry, for example, relies on the mining of lithium and other metals — a process that is itself damaging to the environment. What has your research revealed about the trade-offs humanity is facing in its efforts to combat global climate change, and, how would you suggest we begin to grapple with such trade-offs?

A: Renewable energy can sometimes be positioned as immaterial and inherently redistributive. In some sense these characterizations arise from physical qualities: the sun and wind don’t require extraction, won’t run out, and are distributed across space.

Yet renewable energy must be collected, stored, and transported; it requires financing, metals extraction, and the processing of decommissioned materials. Energy access, mining, and waste deposition are material, geographically situated dynamics. Not everyone stands to benefit equally from renewable energy’s financial and environmental potentials, and not everyone will be equally exposed to its socio-environmental impacts.The distribution of burdens is in some cases already mapping onto existing inequities in power and privilege, disproportionately impacting BIPOC [Black, Indigenous, and people of color] and low-income individuals, as well as communities in the Global South — often in locales also on the front lines of climate change or other forms of environmental injustice.None of these challenges should stall renewable energy implementation; renewables are an absolutely crucial part of climate mitigation and can also increase climate resilience and reduce environmental contamination, among other co-benefits.

Moreover, neither the parameters of these challenges nor the potential interventions are clear-cut. Minerals extraction is key for many local economies.Different metals also have distinct environmental and social footprints. Cobalt mining, which takes place largely in the Democratic Republic of the Congo under environmentally and economically precarious conditions, poses different socio-ecological challenges than copper extraction, which takes place around the world, primarily at large scales via increasingly remote methods. Lithium, meanwhile, can be found in salt flats, igneous rocks, geothermal fluids, and clays, each of which requires different mining techniques.Minimizing the localized burdens of renewable energy implementation will be complex. Here at MIT, researchers are working on technical approaches to develop less-intensive forms of mining, novel battery chemistries, robust energy storage technologies, recycling mechanisms, and policies to extend energy access. Just as important, I think, is understanding the historical processes through which the benefits and burdens of different energies have been distributed — and ensuring that the ethical frameworks by which current and future projects might be mapped and evaluated are sufficiently nuanced.I’m still in the planning phase of my own research, but I hope it will help surface, and offer tools with which to think through, some of these socio-environmental complexities.

Q: In confronting an issue as formidable as climate change, what gives you hope?   A: In college I did an interview project to learn about collaborations between student environmental groups and a local church to address climate change. Toward the end of each interview, I found myself coming back to the same question: What gives you energy in your work on climate change? What keeps you going?The question wasn’t strictly necessary for my project; I was asking, mostly, for myself. Climate change can be truly overwhelming, in part because it so dramatically dwarfs the scope, in space and in time, of a single human life. It is also complex — intertwined with so many different ways of knowing the world.My interviewees gave different answers. Some told me they were careful to mentally segment the issue so as to keep “climate change,” as a paralyzing totality, from sapping a sense of purpose from their daily research or advocacy endeavors. Others I spoke with took the opposite approach, conceptually linking their own efforts — which could feel insufficiently quotidian — to a sense of the broader stakes. But almost everyone I talked to highlighted the importance of being part of a community — of engaging in and through collaborative efforts.That’s what gives me hope as well: people working together to address climate change in ways that attend to both its scientific and its social complexities. Intersections between climate change and social justice like the Sunrise Movement or the Climate Justice Alliance give me hope.Climate-related collaborations are also happening all across MIT; I find the initiatives that have emerged from the Climate Grand Challenges process particularly inspirational. In STS, individuals such as HASTS alum Sara Wylie [PhD ’11], who has researched the impacts of hydraulic fracturing, have built deep relationships with the communities they work within, leveraging their research to support relevant climate justice initiatives.For my part, I’ve been energized by my involvement in a project led by MIT MLK Scholar Luis G. Murillo [former minister of environment and sustainable development in Colombia] that convenes policymakers, community advocates, and researchers to advance initiatives that foment racial justice, conservation, climate mitigation, and peace.

Prepared by MIT SHASS CommunicationsSeries editor and designer: Emily HiestandCo-editor: Kathryn O’Neill More

When he entered the Museo Galieo, Theo Mouratidis was not expecting to make a life-changing decision. Having recently graduated from a high school outside Melbourne, Australia, and looking forward to undergraduate studies at nearby Monash University, he had joined his family for a holiday in Florence, Italy. Stepping inside a museum devoted to the genius of Galileo, one of his “scientific heroes,” Mouratidis was stirred.

“I saw all of his works, his inventions, at that museum,” he recalls, “and that changed it for me. I remember sitting in a café after, and my parents were wondering at how quiet I was. And at some point I just spurted out, ‘I’m going to MIT.’”

The determination, drive, and pure will needed to change course and pursue a transfer to MIT, an institute he had only learned about from his chemistry tutor during his senior year of high school, are qualities evidenced in the way Mouratidis attacks every challenge. Now a graduate student in the Department of Aeronautics and Astronautics, he works daily on what is considered one of the world’s most difficult science and engineering efforts — making fusion energy a viable source of plentiful carbon-free energy for coming generations. Supported by the MIT Energy Initiative as an MIT Energy Fellow, sponsored by Commonwealth Fusion Systems (CFS), Mouratidis is focused on creating special magnets for a future fusion pilot plant called ARC.

Fusion, the energy source of the sun and stars, occurs when two atomic nuclei in a plasma collide and fuse, forming a heavier nucleus and releasing energy in the form of neutrons. Because this plasma responds to magnetic fields, researchers use a doughnut-shaped device called a tokamak to contain it. Wrapped with magnets, a tokamak is designed to keep the hot plasma away from the walls of the toroidal vacuum chamber while fusion reactions take place.

Re-imagining magnets

At MIT’s Plasma Science and Fusion Center (PSFC), where Mouratidis works under the direction of Director Dennis Whyte and Senior Research Scientist Brian LaBombard, scientists have been working with tokamaks for decades, most recently concentrating on SPARC, a fusion experiment that will pave the way for the ARC fusion pilot plant Mouratidis has chosen as his focus.

The magnets for SPARC are revolutionary, made from high-temperature superconducting (HTS) tape so much more compact than previous coils that they will be able to produce significantly higher magnetic fields, consequently increasing the economic success of the tokamak. Moreover, building on concepts developed by LaBombard and PSFC Head of Mechanical Development Bill Beck, the magnet design makes it possible for the conductors to be jointed. Unlike a continuous superconducting coil, these magnets might be able to be disassembled and reassembled while still retaining the electrical characteristics of a continuous coil. This would be a major breakthrough in the assembly and maintenance strategy of tokamaks made with HTS.

Mouratidis has tasked himself with finding a way to build joints for these magnets, which surround the torus of the tokamak at spaced intervals. The key is obtaining the requisite joint resistance and geometry. He is giving himself what he calls “a hell of a challenge.”

“Can I design a demountable joint that will satisfy the electrical requirements I need for this magnet to behave as a stable superconducting coil? And how can we make the design practical for an actual fusion power plant?”

Such a technological advance would allow the magnets to be removed in order to access internal components, which are subject to damage from neutrons created in the fusion process, reducing the need to shut down the tokamak for extended periods of time.

A new path, or two

When Mouratidis first approached the PSFC, he was not expecting to get involved in tokamak research. He was pursuing a master’s degree at MIT in the Department of Aeronautical and Astronautical Engineering, interested in advanced rocket propulsion technology. Although Whyte was receptive to the student’s interest in fusion propulsion, he and Mouratidis eventually realized the funding for such an effort would not be immediately forthcoming.

“Over two years, Dennis and I had been trying to get some funding. But all the avenues were fruitless. I think what he was doing was he was slowly poking SPARC on to me. He told me ‘None of this is going to happen if you haven’t gotten fusion to work first. Don’t worry about fusion propulsion; worry about fusion!’”

This was not the first time Mouratidis had needed to redirect his path. As a high school student excelling in soccer, he had envisioned for himself a professional sports career. That was before he tore his meniscus, not once but three times. After the third operation to repair his knee, the surgeon informed him that this time he could not simply suture the meniscus; he had to remove it. He advised the student to quit soccer.

“That’s tough to hear as a 17-year-old,” says Mouratidis. “But I will say, that was my turning point. That was when I really recognized that, OK, I’ve got a brain, I need to use it for good.”

Though now determined to test his academic strengths, Mouratidis never gave up on testing himself physically. When he arrived at MIT he spent some time rowing. Then, one day in the gym, lifting a dead weight from the floor, he realized he had a talent and the strength for weight-lifting. His decision to commit time and energy to improving his lifting led him to compete in powerlifting tournaments, in the process setting some records. His personal best for the deadlift is 770 pounds.

Balancing his physical drive is a creative spirit, currently employed in coauthoring an educational fiction series for middle school students. The three books planned will provide comprehensive lessons in the fundamentals of physics, including relativity, astrophysics, and his favorite topic — fusion rockets.

While the need to isolate due to Covid-19 has perhaps been a boon to his writing, it has made it impossible for him to compete in powerlifting for the past year. Still, he continues to train, while cultivating a new test of his endurance: climbing mountains.

He admits to having already had a close call or two on the mountain side.

“I always ask myself a question — why do these guys climb the most dangerous mountains in the world and put themselves in the most precarious positions? I think there is an indescribable beauty and freedom in such a challenging endeavor, and an unquenchable thirst within the human condition to want to explore places where few have been. For good or worse, I have a little bit of that. I think there is a necessary amount of risk that you have to take on to grow as a person.”

Taking calculated risks and setting fusion records is something he looks forward to while working on the SPARC tokamak, and ultimately ARC. Crediting the increased magnetic fields that will be available with ARC’s HTS magnets, he observes, “I think that puts us in a position where I could be part of this team that is going to be the first to create a pilot fusion plant and produce net energy.” 

On every path in his life he is determined to reach the summit. More