Back in the day … When Writing … was a beautiful Work of Art
Deep learning–based data analysis software by ORNL promises to accelerate materials research: AI Applications
Researchers at the Department of Energy’s Oak Ridge National Laboratory have developed a machine-learning inspired software package that provides end-to-end image analysis of electron and scanning probe microscopy images.
Known as AtomAI, the package applies deep learning to microscopy data at atomic resolutions, thereby providing quantifiable physical information such as the precise position and type of each atom in a sample.
Using these methods, researchers can quickly derive statistically meaningful information from immensely complex datasets. These datasets routinely include hundreds of images that each contain thousands of atoms and abnormalities in molecular structure.
This improvement to data analysis allows researchers to engineer quantum atomically precise abnormalities in materials, and can be used to gain deeper insights into the materials’ physical and chemical qualities.
Electron microscopy and scanning probe microscopy allow materials scientists, physicists and other researchers to probe atomic and molecular structures at extremely high resolutions. These high-resolution methods allow researchers to clearly observe atomic structures, making them an important tool in understanding and engineering materials at the nanoscale.
Electron microscopy is useful for gaining precise information on the structure of a material, whereas scanning probe microscopy is more often used to learn about a material’s functional properties, such as superconductivity or magnetism. Both methods benefit from modern image analysis methods.
Deep learning is a kind of machine learning that allows a program to train itself to accurately identify the contents of an image or block of text. When traditional machine learning is applied to image analysis, relevant features are manually extracted from a set of images — a process known as feature engineering — and used to create a model that categorizes objects based on those features.
In contrast, deep learning models automatically learn relevant features by using a network of layered “neurons” — biologically-inspired nodes through which data and computations flow — trained to detect various aspects of an image at different levels of complexity.
This allows for increased precision and the analysis of more diverse information when compared with traditional machine learning, so long as enough data exists to train the system.
AtomAI, which was developed partially at ORNL’s Center for Nanophase Materials Science, includes a unique model architecture to identify thin objects such as nanofibers or domain walls — the interfaces separating magnetic domains — in microscopy data. The software package is also built to reduce errors in image processing by accounting for unintended changes in the image data, such as incoming cosmic rays or images of non-target materials, and by incorporating certain unchanging physical characteristics into the model.
Also, AtomAI includes tools that allow researchers to conduct real-time analysis of the data being gathered and to import information directly into theoretical simulations. These features are useful for gaining insights into the energetics and optical, electronic and magnetic properties of the physical structures being observed.
An overview of the software package was published in Nature Machine Intelligence.
“People used to treat microscopy as a purely qualitative tool,” said Maxim Ziatdinov, a researcher at ORNL and the lead developer of AtomAI, “but recently there was sort of a shift in the mindset of the community: Microscopy can actually be used to extract quantitative physical information.” Qualitative microscopy methods generally rely on researchers noting holistic information about a sample, while the new quantitative methods allow for precise numerical representations of a material’s structure or properties.
Software such as AtomAI has enabled this shift, providing a method to quantitatively analyze the structures of whole samples to find meaningful data that qualitative methods might misrepresent or simply not notice.
Ziatdinov expects his team’s work to accelerate the rate of progress in both fundamental and applied materials research. “If you can characterize things faster and automate at least some parts of the process, then you will also speed up all aspects of materials science research,” he said.
AtomAI was designed with ease of use and access in mind. The entire package can be launched from a browser and requires minimal coding knowledge to operate.
“If you’re an experimentalist, then you should be able to use machine learning without knowing all the math behind the process and without necessarily being a good coder,” Ziatdinov said.
AtomAI is a complete software package, and Ziatdinov and his team expect to expand its capabilities and support more features. He is particularly interested in adding functionality for theoretical researchers looking for accurate estimates of structures’ physical characteristics, such as energetics and stability, without going through the time-consuming and expensive process of traditional simulations.
Ziatdinov is also looking forward to hearing directly from other researchers about their needs and ideas for AtomAI and is working with them to integrate new features into the software package.
ORNL is managed by UT-Battelle for DOE’s Office of Science, the single largest supporter of basic research in the physical sciences in the United States. DOE’s Office of Science is working to address some of the most pressing challenges of our time. For more information, visit energy.gov/science. – Galen Fader
Lipid nanoparticles engineered to specifically target pancreas in mouse model
Therapeutics that use mRNA—like some of the COVID-19 vaccines—have enormous potential for the prevention and treatment of many diseases. These therapeutics work by shuttling mRNA “instructions” into target cells, providing them with a blueprint to make specific proteins. These proteins could help tissues to regenerate, replace misfunctioning proteins, or prompt an immune response, providing a variety of different treatment strategies.
However, a therapeutic is only useful if it can reach its target. The mRNA is typically packaged inside a lipid nanoparticle, which keeps the delicate cargo intact until it reaches its final destination. As the field stands now, mRNA-filled lipid nanoparticles generally reach just a handful of cell types, such as immune cells and cells in the liver or spleen. Designing such lipid nanoparticles that can target hard-to-reach organs, such as the heart or pancreas, could revolutionize treatment options for a wide range of conditions.
In response to this need, researchers at Carnegie Mellon University are developing lipid nanoparticles that are designed to carry mRNA specifically to the pancreas. Their study in mice, recently published in Science Advances, could pave the way for novel therapies for intractable pancreatic diseases, such as diabetes and cancer.
“Lipid nanoparticles are essentially tiny spheres of fat, and fats have all kinds of chemical properties that can affect their ability to travel through the body and target specific organs,” explained Luisa Russell, Ph.D., a program director in the Division of Discovery Science & Technology at the National Institute of Biomedical Imaging and Bioengineering (NIBIB). “By optimizing these fat molecules and investigating alternative drug delivery routes, the study authors were able to design a lipid nanoparticle that can safely deliver mRNA to pancreatic tissue in mice.”
Current mRNA drug delivery routes include intramuscular injection (used in COVID-19 vaccines) and intravenous administration (used in some investigational cancer therapeutics). As a first step towards targeted delivery, the study authors wanted to know if a different administration route might help deliver the mRNA cargo directly to the pancreas. They investigated mRNA delivery via intraperitoneal injection, which involves injecting a drug directly into the fluid that surrounds the organs of the peritoneal cavity (including the kidneys, intestines, and pancreas).
“While intraperitoneal injection is not commonly used in humans, this type of administration is used clinically for some difficult-to-treat diseases, such as ovarian cancer,” said senior study author Kathryn Whitehead, Ph.D., a professor at Carnegie Mellon University. “With very serious pancreatic diseases, the benefits of intraperitoneal injection outweigh the risks.”
The researchers packaged mRNA instructions for firefly luciferase—a bioluminescent protein often used in research—into lipid nanoparticles, and then injected them into mice either intravenously or intraperitoneally. Using the glowing firefly luciferase to see where the mRNA had traveled, they found that intraperitoneal injection resulted in more abundant and more specific delivery to the pancreas compared with intravenous injection.
Next, the researchers began to optimize the composition of fat molecules that make up the nanoparticle. Different fats have unique chemical properties—such as size, electrical charge, and hydrophobicity—that can affect what happens to the nanoparticle once it enters the body. One type of fat molecule used is called a “helper lipid,” so named because it helps to stabilize the nanoparticle and improves its potency. The researchers wanted to know if changing the charge of the helper lipid might affect the targeting of the nanoparticle and direct it towards the pancreas. After trying a variety of different nanoparticle compositions, the researchers found a combination of lipids that improved pancreatic targeting in mice.
“Within the past couple of years, there’s been much more appreciation for how the lipids in nanoparticles can redirect mRNA delivery to different cells and organs,” said first study author Jilian Melamed, Ph.D., a postdoctoral researcher at the University of Pennsylvania. “The precise ways that lipid chemistry affects the potency and specificity of nanoparticles are still being uncovered, and we are still working to understand how individual lipid components influence overall mRNA delivery.”
When the authors investigated where exactly their optimized nanoparticles were going in the pancreas, they were surprised to discover that mRNA was most abundant in pancreatic islet cells, which comprise only 1%–2% of total pancreatic tissue. Pancreatic islet cells are responsible for producing hormones that control glucose in the blood (such as insulin). Such specific targeting could have potential downstream clinical applications.
“With further development, our research may lead to the creation of therapies for diabetes or certain types of pancreatic cancer,” said Whitehead. “These potential treatments, however, would require more preclinical research before advancing to clinical trials.”
Elon Musk – Tesla Make Big Cuts … Globally – Harbinger of the Future?
Teslas just got a whole lot cheaper.
The Elon Musk led automaker has cut prices across the board on its new models of EVs — as much as 20 percent cheaper — in the US and Europe, following substantial price cuts in China and other Asian markets that rolled out earlier this month.
The most affordable EV from Tesla’s lineup, the standard Model 3, went down from $46,990 to $43,990, a six percent drop. Not super drastic, but we’re just getting started.
Take the Model Y, which got the biggest slash of a whopping 20 percent, down from $65,990 to $52,990. That also means that the Model Y now qualifies for the $7,500 tax credit for EVs as part of the Inflation Reduction Act.
The company’s uber expensive cars, like the Model S, dropped ten percent from $104,990 to $94,990, and the Model X a nine percent fall, from $120,990 to $109,990.
Performance and Plaid versions of certain models also received significant cuts. The Model S Plaid, for example, fell 15 percent from $135,990 to $114,990, making it the biggest slash by sheer dollar amount at a $21,000 drop.
Up and Down Again
These price cuts are nothing to sneeze at, but also highlight how expensive Teslas had been previously, receiving multiple price hikes last year amid surging inflation.
There’s good reason that the price drop is coming now. As Reuters reports, Tesla missed its quarterly deliveries estimates for the end of last year, although it experienced a 40 percent rise in deliveries for the year overall. Still, that raised concerns over demand, especially in the domestic market.
Likely the biggest impetus for Tesla, however, was its dramatically declining stock in 2022, which it is yet to rebound from. Overall, it lost 65 percent of its valuation, or around $700 billion — making it Tesla’s worst year in its stock history.
Tesla stock took another minor blow after these most recent price cuts, dropping another 4.5 percent according to Reuters, but obviously the company expects the move to pay off in the long run.
The Latest Genesis Nanotech Online Is Out! “It’s All About the Mind” – Articles Like “Tuning into brainwave rhythms speeds up learning in adults U of Cambridge + More ….
Scientists have shown for the first time that briefly tuning into a person’s individual brainwave cycle before they perform a learning task dramatically boosts the speed at which cognitive skills improve.
Calibrating rates of information delivery to match the natural tempo of our brains increases our capacity to absorb and adapt to new information, according to the team behind the study.
University of Cambridge researchers say that these techniques could help us retain “neuroplasticity” much later in life and advance lifelong learning.
Read the rest of this Article and More in Genesis Nanotech Online at: Genesis Nanotechnology Online
Building A Better Battery for America … In America – Is Lithium Iron Phosphate (LIP) Making a ‘Comeback’ in North America?
Credit: David Giral Photography | Nano One Materials’s Montreal factory, originally commissioned in 2012, is the only facility in North America that can produce meaningful quantities of lithium iron phosphate.
Electric car companies in North America plan to cut costs by adopting batteries made with the raw material lithium iron phosphate (LFP), which is less expensive than alternatives made with nickel and cobalt.
Many carmakers are also trying to reduce their dependence on components from China, but nearly all LFP batteries and the raw materials used to make them currently come from China. A number of companies are now planning the first large-scale LFP factories in North America. Some are partnering with established companies, and others hope to introduce new technologies that will leapfrog Chinese competitors.
THE REST OF THE STORY
On a bookshelf in his home near Montreal, Denis Geoffroy keeps a small vial of lithium iron phosphate, a slate gray powder known as LFP. He made the material nearly 20 years ago while helping the Canadian firm Phostech Lithium scale up production for use in cathodes, which is the positive end of a battery and represents the bulk of its cost.
At the time, Phostech was making only about 1 metric ton (t) of LFP per year. Geoffroy mixed the precursors at a facility in Quebec and cooked the mixture in a kiln in Ontario, more than 700 km away. “Then I would put it in my car and drive home,” he says. “I would go to FedEx to ship it to customers.”
Eventually, Phostech graduated to bigger LFP factories, culminating in a 2,400 t per year plant near Montreal in 2012. Despite the progress, LFP never caught on as a chemistry for electric vehicle batteries in North America. Carmakers in the region opted instead for cathodes made with nickel and cobalt, which offer higher energy density and more range. In 2021, Johnson Matthey, which acquired the Montreal facility in 2015, put the plant up for sale.
Nickel and cobalt prices have increased substantially in the past few years, however, and nonprofit watchdogs say mining for the metals is connected to environmental problems and child labor. Nickel-based batteries are also more likely to catch fire and can’t be recharged as many times as LFP batteries.
After initially snubbing the chemistry, several big carmakers are now turning to LFP as a way to cut lithium-ion battery costs.
Ford, Rivian, and Volkswagen have all unveiled plans to use LFP in North American cars, and General Motors is interested as well. A turning point came in October 2021, when Tesla, which accounted for two-thirds of US electric car registrations last year, revealed that it would switch to LFP batteries for all its standard-range vehicles globally.
Western carmakers also want to reduce their dependence on materials from China. At the moment, China is the source of nearly all LFP batteries and the cathode powders required to make them, but several companies are trying to change that.
In October, the Israeli chemical maker ICL Group announced plans to build an LFP cathode powder factory in Missouri. The Norwegian start-up Freyr Battery and Utah-based American Battery Factory plan to make LFP cathode material in the US for their battery factories in Georgia and Arizona, respectively. Meanwhile, China’s Gotion High-Tech hopes to establish LFP cathode material production in Michigan. Other Chinese manufacturers are also weighing how to leverage their expertise in North America.
In November, the start-up Nano One Materials finalized the purchase of the old Phostech LFP plant in Montreal, promising to introduce a manufacturing process that will require less energy and produce less waste than existing methods. Geoffroy, now Nano One’s chief commercialization officer, has returned to the factory to pilot the new process and scale it up.
“I designed it, built it, managed it, left it . . . and now we’re rebuilding,” Geoffroy says. “For me, it’s a chance to do what I planned on doing with a process that I believe in.”
BORN IN THE USA
The energy powering an electric car is released when electrons from a lithium-ion battery’s negatively charged electrode, called the anode, flow through the motor into the battery’s positively charged cathode. To balance the electrons leaving the anode, the cathode must simultaneously accept positively charged lithium ions from an electrolyte solution.
Batteries with anodes that produce lots of electrons, and cathodes that are eager to suck them up, have a high voltage, which allows them to store more energy in a given volume. Energy density can be increased by using cathode and anode materials that can store more lithium ions.
Because nickel and cobalt cathode materials can store lots of lithium and generate a high voltage, they were used in some of the first commercial lithium-ion batteries. But even in the early days of battery development, researchers saw room for improvement.
Nano One Materials must scale up its new production process from 100 L glass tanks to much larger factories. Initial trials started this month. Credit: David Giral Photography
“We wanted to reduce the cost, so we pursued cathodes based on iron, which is abundant and a cheaper metal,” says Arumugam Manthiram, a University of Texas at Austin researcher who worked with the battery trailblazer John Goodenough for decades and laid the groundwork for the class of cathodes that includes LFP.
In the mid-1990s, other researchers from Goodenough’s lab proposed using LFP, arguing that it was cheap and nontoxic. But the material wasn’t very conductive, which limited its utility. A few years later, building on the Goodenough lab’s initial discovery, scientists at Hydro-Québec and the University of Montreal solved the conductivity problem by coating LFP with carbon. Though LFP batteries still couldn’t match the energy density of nickel-based batteries, their lower cost made them appealing.
In 2003, Hydro-Québec and the University of Montreal gave Phostech the first license to manufacture LFP commercially. But investors backing North American projects were cautious, and progress was slow. “We had half a million dollars to survive for 3 years,” Geoffroy recalls. “I was paying myself by selling samples.”
Things accelerated for Phostech in 2005, when the German chemical company Süd-Chemie, which was developing a different LFP manufacturing process, bought a majority stake in Phostech. Süd-Chemie financed pilot facilities and the 2,400 t plant near Montreal, but the German firm’s hydrothermal process turned out to be more expensive than Phostech’s solid-state method. Clariant acquired Süd-Chemie in 2012 and promptly sold the LFP business to Johnson Matthey.
Geoffroy left Johnson Matthey in 2019 without seeing the plant become big enough to meaningfully supply the auto industry. “When we bought the land in 2007 there was expansion planned,” he recalls. “We never expanded.”
Other North American companies also sought to capitalize on the discovery of LFP, with limited success. In 2009, the Massachusetts Institute of Technology spinout A123 Systems raised $350 million in an initial public offering, aiming to manufacture a modified version of LFP in Michigan. But not enough carmakers were interested, and A123 went bankrupt in 2012. Most of the firm’s assets were acquired by China’s Wanxiang Group.
MADE IN CHINA
LFP was invented and developed in North America, but Chinese companies were the first to place a big bet on the technology, according to Karim Zaghib, a battery scientist at Concordia University who worked for Hydro-Québec in the 1990s.
After successfully installing LFP batteries on buses ahead of the 2008 Beijing Olympics, China, impressed by the chemistry’s improved fire safety compared with nickel-based batteries, made LFP production a national project, Zaghib says. “The Chinese government and Chinese companies invested a lot in LFP.”
And the material has been a hit. In 2021, more than 40% of electric vehicles sold in China had LFP in their batteries, according to the market research firm Adamas Intelligence. “In China, small electric vehicles . . . with a range of 120 km are very popular,” says Alla Kolesnikova, head of data analytics at Adamas. “The majority of them are powered by LFP.”
Most factories in China produce LFP using a solid-state process that starts with the reaction of iron sulfate and phosphoric acid to produce iron phosphate. Usually the iron phosphate is then mixed with lithium carbonate and a source of carbon that forms the conductive coating.
Taiwan’s Aleees has been producing lithium iron phosphate outside China for decades and is now helping other firms set up factories in Australia, Europe, and North America. Credit: Aleees
That mixture is then sent in a ceramic crucible into a kiln, where it reaches temperatures of 700–800 °C. The heat sinters the material, changing it from an amorphous mixture into the olivine structure that allows it to function as a cathode.
Between 2010 and 2016, China’s capacity to make LFP cells, or individual battery units, increased 100-fold, according to Cormac O’Laoire, managing director of the Hong Kong–based battery consulting firm Electrios Energy. By 2021, he says, Chinese companies were producing over 90% of the world’s LFP powder.
In a little over 10 years, one Chinese company, Shenzhen Dynanonic, increased its annual LFP capacity from 500 t to 265,000 t. Unlike other firms in China, Dynanonic uses a solution-based production method that resembles the hydrothermal process Süd-Chemie used in Montreal.
Suki Zhang, Dynanonic’s account manager for overseas markets, says most of its growth has come in the past 2 years, a period when Chinese battery manufacturers, such as Contemporary Amperex Technology Co. Limited (CATL), were investing heavily in LFP. “We have so many batteries here,” she says. “The demand is a big reason why we built LFP in China.”
Chinese factories are able to make LFP cheaply, in part because the consortium of organizations that owned the relevant patents—including France’s National Center for Scientific Research, Hydro-Québec, Johnson Matthey, and the University of Montreal—agreed not to charge Chinese companies licensing fees if they sold only in China, according to an International Energy Agency report. In contrast, the Taiwan-based LFP maker Aleees says it paid about 10% of its sales in licensing fees until recently.
The intellectual property was held more closely in other parts of the world. “That may have limited some of the development of LFP in the US and Europe,” says Anantha Desikan, ICL’s chief technology officer.
James Frith, a principal at the venture capital firm Volta Energy Technologies, points out that China has other advantages. Iron sulfate is cheap there because it’s available as a by-product of titanium dioxide production, which isn’t the case outside China, where most makers of the pigment use a different process. Frith says less-stringent environmental regulations in China can also reduce costs.
Over the past few years, the core patents behind LFP manufacturing have expired, removing a barrier for non-Chinese companies interested in producing LFP. O’Laoire says the expirations also make it easier for Chinese companies to serve markets where the patents were previously enforced.
Zhang says Dynanonic is now considering an overseas expansion, though the company hasn’t yet disclosed a specific location. Any such project would depend on the strength of battery manufacturing in other countries as well as on the rules for implementing clean energy policies like the Inflation Reduction Act, the landmark US legislation that is projected to inject $142 billion into companies making batteries or battery components in the US.
Other Chinese battery companies have already started expanding overseas. Gotion High-Tech, which has been producing LFP batteries and cathode materials in China since 2007, plans to build 100 GW h of battery cell capacity outside China over the next 3 years. In June 2022, Gotion, whose biggest shareholder is Volkswagen, announced plans for its first LFP battery factory in Europe.
A scanning electron microscope image of Aleees’s lithium iron phosphate powder. Credit: Aleees
A few months later, an economic development agency in Michigan awarded Gotion’s US subsidiary grants and tax incentives to help construct a $2.4 billion plant in Big Rapids, Michigan. If built as planned, the factory will produce 150,000 t of LFP cathode material per year.
“The companies that understand how to make the product are looking to expand in other regions,” Chuck Thelen, a Gotion vice president, said at a December informational meetinghosted by Big Rapids officials.
Some Western firms setting up LFP cathode production in North America plan to work with partners and use established processes. Others hope to outcompete Chinese firms with new technologies.
ICL, which produces industrial phosphates and other chemicals, has been on the periphery of the LFP industry for years. It analyzed cathode materials from A123 before the company went bankrupt and began providing phosphate raw materials to LFP firms in China in 2021. In early 2022, ICL decided LFP had gained enough momentum outside China to warrant venturing into battery materials on its own.
US demand for lithium iron phosphate (LFP) batteries in passenger electric vehicles is expected to continue outstripping local production capacity. Source: BloombergNEF.
In October 2022, the company received a $200 million US Department of Energy grant to build a 30,000 t per year LFP cathode material factory at its Saint Louis site, which has been producing phosphorus chemicals for more than a century. “We’ve been making phosphate salts since 1876,” says Tom Murray, ICL’s director of R&D. “Lithium iron phosphate is not very different.”
One potential difference from Chinese factories could be ICL’s starting materials. The company is evaluating using iron oxide rather than iron sulfate, which can be difficult to procure outside China. Iron oxide is more expensive, but Murray says the process produces higher-quality LFP.
At the Missouri plant, ICL will use technology from Aleees, which has been manufacturing LFP materials for nearly 2 decades. Murray says the partnership combines Aleees’s deep experience in high-quality LFP production with ICL’s expertise in large-scale chemical manufacturing. “Without them, it would be a struggle for us to jump into this and make any headway,” he says.
We’ve been making phosphate salts since 1876. Lithium iron phosphate is not very different.” Thomas Murray, director of R&D, ICL Group
Eric Chang, president of Aleees’s licensing business, says the company is eager to partner with companies like ICL because its ability to expand in Taiwan is limited by the price of land. Over the last 6 months, the company has also agreed to provide its cathode manufacturing technology to Norway’s Freyr and Australia’s Avenira.
In November, Freyr announced that it would build a $1.7 billion, 34 GW h battery factory in Georgia, and Chang says Aleees plans to help Freyr make LFP cathode materials to supply that plant.
American Battery Factory, a Utah-based company that hopes to serve the stationary energy storage market, is also partnering with an established cathode manufacturer, as yet unnamed, to set up production of LFP cathode materials in the US. The powder it makes would supply the company’s proposed cell factory in Arizona and could also be sold to other companies.
Denis Geoffroy helped build two lithium iron phosphate factories in Canada, but the material never caught on in North America. He’s now trying again with Nano One Materials. Credit: David Giral Photography
Frith says China’s cheap labor, energy, and raw materials will make it difficult for Western firms to match the country’s low cost of production, but provisions in the Inflation Reduction Act may give companies in the US enough of a boost. “Without that, I think you’re unlikely to find LFP production moving outside of China,” he says. “The economics just aren’t really there to promote it.”
While Aleees’s product costs more than LFP made in China, Chang argues that the firm is better than Chinese competitors at customizing its output for specific customers. “They lack the flexibility to fine-tune the parameters or the characteristics or properties of LFP,” he says. “They make it more like a commodity rather than a specialty chemical.”
Some Western companies are hoping to beat Chinese competitors with new technologies that can produce high-quality LFP with a lower environmental footprint.
Nano One CEO Dan Blondal says imitating China’s solid-state process in North America could be challenging because it creates lots of sulfate waste. “China largely sweeps it under the rug,” he says. “As you try to bring that out of China to everywhere else, it’s a big impediment. It’s gonna be hellish to permit that.”
Instead, Nano One plans to use pure iron metal as an LFP precursor, eliminating the sulfate waste stream. The company also claims that this method makes the cooking step more efficient, saving energy.
Nano One is just starting to set up shop at its recently purchased Montreal factory. Temporary banners with the company’s name hang from the ceiling, but the plant’s handful of employees still wear Johnson Matthey uniforms, and bags of LFP left over from the transition bear the Johnson Matthey logo.
On the factory floor, the 100 L glass reactor Nano One currently uses for its process looks small in front of the 20 m3 stainless steel reactor Johnson Matthey used to make LFP.
Geoffroy’s task is to retrofit that reactor and the rest of the Montreal facility to work with the process. The next step is to build a new factory next door to demonstrate the technology at a larger scale. While the two plants will be substantial, they will largely serve as a blueprint for still-larger plants Nano One wants to build through joint ventures or licensing deals with bigger companies.
The Montreal plant was designed for an entirely different process, so scaling up will be a long road. Pointing to a hatch at the top of a large reactor, Geoffroy says testing the Nano One process may initially require dumping raw materials in by hand.
But Geoffroy points out that he, along with much of his team, went through this twice when they built a solid-state plant for Phostech and the hydrothermal plant for Süd-Chemie. The only difference now is that the size will be much bigger. “All the LFP made in North America commercially was really made here,” he says. “All that knowledge is there. We inherit that.”
Nano One hopes to use iron powder from Rio Tinto’s metal processing facility in Sorel-Tracy, Quebec. Credit: Rio Tinto
The Massachusetts start-up 6K also wants to challenge established Chinese players with a cathode material manufacturing process that uses less energy and produces less waste.
“We have to leapfrog because we can’t compete directly with the same technology,” 6K CEO Aaron Bent says. In the US, “the workforce is more expensive, electricity is more expensive,” he says. “You’ve got to have a massively differentiated approach.”
6K’s approach involves injecting a precursor mixture containing lithium, iron, and phosphorus chemicals into a microwave plasma reactor that reaches 5,700 °C. The company says the heat and reactive ions in the plasma turn the precursors into a cathode material in a matter of seconds, eliminating the need for a kiln baking step, and most of the by-products can be recycled back into the process to reduce waste.
Like ICL, 6K received a DOE grant in October. Its research center can currently produce up to 400 t of cathode material annually, and the firm hopes to build a 10,000 t plant by 2026. 6K is also working with the US battery firm Our Next Energy to install LFP cathode production capacity at a cell factory in Michigan.
“We have to leapfrog because we can’t compete directly with the same technology.” Aaron Bent, CEO, 6K
Zaghib, the Concordia University battery scientist, is skeptical that new technology is the key to building an LFP ecosystem in North America. He says the solid-state process works well, and new technologies will struggle to match its price. “If we want to accelerate LFP we need GM, Ford . . . Tesla, or some government to start putting up money,” he says.
Ford hopes to partner with CATL to build LFP battery capacity locally, but in January, Virginia governor Glenn Youngkin said he had nixed a proposal for a CATL factory in his state, according to the Virginia Mercury. For now, Ford and other carmakers will rely on batteries produced in China.
The companies planning to make LFP materials in North America are betting that the lower cost of LFP-powered cars will help overcome US consumers’ anxieties about their limited range, but that’s far from a guarantee. US drivers love road trips and SUVs, which typically require large-capacity batteries.
“Our driving patterns are so different from what you see in Asia and in Europe,” says Michael Sanders, a battery industry analyst with Avicenne Energy. “I think range anxiety is going to play a much bigger role here in North America.”
There are several ways around the problem. CATL and BYD Auto, another Chinese battery maker, have engineered their LFP battery packs to be hyperefficient, increasing capacity by cramming extra cathode material into the same amount of space. Ford wants to use that technology in its LFP vehicles.
It’s also possible to use a combination of battery chemistries. Our Next Energy hopes to combine a primary LFP battery suitable for everyday use with a small lithium-metal battery that could boost a car’s range when needed. Lithium-metal batteries carry more energy than other battery chemistries, but they have yet to be commercialized, in part because they degrade after a small number of charge-discharge cycles.
6K is hoping to set up its new cathode manufacturing technology at a battery plant operated by Our Next Energy. Until then, Our Next Energy will rely on cathode material from overseas. Credit: Our Next Energy
Another approach is simply to make iron-based batteries better. That’s what the California start-up Mitra Chem is trying to do. The company uses machine learning to create new cathode materials that combine iron with other metals, such as manganese, to increase the energy density. “We ultimately want to get to . . . LFP 2.0, LFP 3.0, higher-energy-density products that can compete . . . with nickel,” says Vivas Kumar, cofounder and CEO of Mitra Chem.
Despite LFP’s lower energy density, many analysts, including Sanders, say technology improvements and low costs mean the battery chemistry will find a place in North America. BloombergNEF says there were no US cars powered by LFP in 2020, but it expects demand for LFP-powered cars to exceed 160 GW h by the end of the decade, representing 40% of the total demand for electric cars.
When those data were published in September 2022, only a handful of companies had announced plans to build LFP factories in the US. Several have since stepped up, and Yayoi Sekine, head of energy storage at BloombergNEF, says she thinks more will come, especially as the Inflation Reduction Act encourages battery makers to build a US supply chain.
Geoffroy remembers when demand for LFP-powered cars was near zero in North America. About 10 years ago, when he was working at one of Phostech’s early plants, he decided to buy something made with LFP from his facility. Unfortunately, a car wasn’t an option. “I bought some small LFP batteries to power my electric trolling motor when I go fishing,” he says. “So I’m powered by LFP.”
As Nano One and other companies start building LFP factories in North America, Geoffroy is hoping for something more substantial. The moment a car built with LFP from his facility becomes available, he’s going to buy it.
This story was updated on Jan. 30, 2023, to correctly spell the name of Nano One Materials’ CEO. It is Dan Blondal, not Don Blondal.
Renewable Energy’s Climb to the Top: Five Major Types of Renewable Energy & Their Potential Impact
The Renewable Energy Age
Awareness around climate change is shaping the future of the global economy in several ways.
Governments are planning how to reduce emissions, investors are scrutinizing companies’ environmental performance, and consumers are becoming conscious of their carbon footprints. But no matter the stakeholder, energy generation and consumption from fossil fuels is one of the biggest contributors to emissions.
Therefore, renewable energy sources have never been more top-of-mind than they are today.
The Five Types of Renewable Energy
Renewable energy technologies harness the power of the sun, wind, and heat from the Earth’s core, and then transforms it into usable forms of energy like heat, electricity, and fuel.
The above infographic uses data from Lazard, Ember, and other sources to outline everything you need to know about the five key types of renewable energy:Energy Source% of 2021 Global Electricity GenerationAvg. levelized cost of energy per MWhHydro 💧 15.3%$64Wind 🌬 6.6%$38Solar ☀️ 3.7%$36Biomass 🌱 2.3%$114Geothermal ♨️ <1%$75
Editor’s note: We have excluded nuclear from the mix here, because although it is often defined as a sustainable energy source, it is not technically renewable (i.e. there are finite amounts of uranium).
Though often out of the limelight, hydro is the largest renewable electricity source, followed by wind and then solar.
Together, the five main sources combined for roughly 28% of global electricity generation in 2021, with wind and solar collectively breakingthe 10% share barrier for the first time.
The levelized cost of energy (LCOE) measures the lifetime costs of a new utility-scale plant divided by total electricity generation. The LCOE of solar and wind is almost one-fifth that of coal ($167/MWh), meaning that new solar and wind plants are now much cheaper to build and operate than new coal plants over a longer time horizon.
With this in mind, here’s a closer look at the five types of renewable energy and how they work.
Wind turbines use large rotor blades, mounted at tall heights on both land and sea, to capture the kinetic energy created by wind.
When wind flows across the blade, the air pressure on one side of the blade decreases, pulling it down with a force described as the lift. The difference in air pressure across the two sides causes the blades to rotate, spinning the rotor.
The rotor is connected to a turbine generator, which spins to convert the wind’s kinetic energy into electricity
2. Solar (Photovoltaic)
Solar technologies capture light or electromagnetic radiation from the sun and convert it into electricity.
Photovoltaic (PV) solar cells contain a semiconductor wafer, positive on one side and negative on the other, forming an electric field. When light hits the cell, the semiconductor absorbs the sunlight and transfers the energy in the form of electrons. These electrons are captured by the electric field in the form of an electric current.
A solar system’s ability to generate electricity depends on the semiconductor material, along with environmental conditions like heat, dirt, and shade.
Geothermal energy originates straight from the Earth’s core—heat from the core boils underground reservoirs of water, known as geothermal resources.
Geothermal plants typically use wells to pump hot water from geothermal resources and convert it into steam for a turbine generator. The extracted water and steam can then be reinjected, making it a renewable energy source.
Similar to wind turbines, hydropower plants channel the kinetic energy from flowing water into electricity by using a turbine generator.
Hydro plants are typically situated near bodies of water and use diversion structures like dams to change the flow of water. Power generation depends on the volume and change in elevation or head of the flowing water.
Greater water volumes and higher heads produce more energy and electricity, and vice versa.
Humans have likely used energy from biomass or bioenergy for heat ever since our ancestors learned how to build fires.
Biomass—organic material like wood, dry leaves, and agricultural waste—is typically burned but considered renewable because it can be regrown or replenished. Burning biomass in a boiler produces high-pressure steam, which rotates a turbine generator to produce electricity.
Biomass is also converted into liquid or gaseous fuels for transportation. However, emissions from biomass vary with the material combusted and are often higher than other clean sources.
When Will Renewable Energy Take Over?
Despite the recent growth of renewables, fossil fuels still dominate the global energy mix.
Most countries are in the early stages of the energy transition, and only a handful get significant portions of their electricity from clean sources. However, the ongoing decade might see even more growth than recent record-breaking years.
The IEA forecasts that, by 2026, global renewable electricity capacity is set to grow by 60% from 2020 levels to over 4,800 gigawatts—equal to the current power output of fossil fuels and nuclear combined. So, regardless of when renewables will take over, it’s clear that the global energy economy will continue changing.
Artificial Intelligence (AI) Discovers New Nanostructures – Brookhaven Center for Functional Nanomaterials
Scientists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory have successfully demonstrated that autonomous methods can discover new materials.
The artificial intelligence (AI)-driven technique led to the discovery of three new nanostructures, including a first-of-its-kind nanoscale “ladder.” The research was published today in Science Advances.
The newly discovered structures were formed by a process called self-assembly, in which a material’s molecules organize themselves into unique patterns. Scientists at Brookhaven’s Center for Functional Nanomaterials (CFN) are experts at directing the self-assembly process, creating templates for materials to form desirable arrangements for applications in microelectronics, catalysis, and more. Their discovery of the nanoscale ladder and other new structures further widens the scope of self-assembly’s applications.
“Self-assembly can be used as a technique for nanopatterning, which is a driver for advances in microelectronics and computer hardware,” said CFN scientist and co-author Gregory Doerk. “These technologies are always pushing for higher resolution using smaller nanopatterns. You can get really small and tightly controlled features from self-assembling materials, but they do not necessarily obey the kind of rules that we lay out for circuits, for example. By directing self-assembly using a template, we can form patterns that are more useful.”
Staff scientists at CFN, which is a DOE Office of Science User Facility, aim to build a library of self-assembled nanopattern types to broaden their applications. In previous studies, they demonstrated that new types of patterns are made possible by blending two self-assembling materials together.
“The fact that we can now create a ladder structure, which no one has ever dreamed of before, is amazing,” said CFN group leader and co-author Kevin Yager. “Traditional self-assembly can only form relatively simple structures like cylinders, sheets, and spheres. But by blending two materials together and using just the right chemical grating, we’ve found that entirely new structures are possible.”
Blending self-assembling materials together has enabled CFN scientists to uncover unique structures, but it has also created new challenges. With many more parameters to control in the self-assembly process, finding the right combination of parameters to create new and useful structures is a battle against time. To accelerate their research, CFN scientists leveraged a new AI capability: autonomous experimentation.
In collaboration with the Center for Advanced Mathematics for Energy Research Applications (CAMERA) at DOE’s Lawrence Berkeley National Laboratory, Brookhaven scientists at CFN and the National Synchrotron Light Source II (NSLS-II), another DOE Office of Science User Facility at Brookhaven Lab, have been developing an AI framework that can autonomously define and perform all the steps of an experiment. CAMERA’s gpCAM algorithm drives the framework’s autonomous decision-making. The latest research is the team’s first successful demonstration of the algorithm’s ability to discover new materials.
“gpCAM is a flexible algorithm and software for autonomous experimentation,” said Berkeley Lab scientist and co-author Marcus Noack. “It was used particularly ingeniously in this study to autonomously explore different features of the model.”
“With help from our colleagues at Berkeley Lab, we had this software and methodology ready to go, and now we’ve successfully used it to discover new materials,” Yager said. “We’ve now learned enough about autonomous science that we can take a materials problem and convert it into an autonomous problem pretty easily.”
To accelerate materials discovery using their new algorithm, the team first developed a complex sample with a spectrum of properties for analysis. Researchers fabricated the sample using the CFN nanofabrication facility and carried out the self-assembly in the CFN material synthesis facility.
“An old school way of doing material science is to synthesize a sample, measure it, learn from it, and then go back and make a different sample and keep iterating that process,” Yager said. “Instead, we made a sample that has a gradient of every parameter we’re interested in. That single sample is thus a vast collection of many distinct material structures.”
Then, the team brought the sample to NSLS-II, which generates ultrabright X-rays for studying the structure of materials. CFN operates three experimental stations in partnership with NSLS-II, one of which was used in this study, the Soft Matter Interfaces (SMI) beamline.
“One of the SMI beamline’s strengths is its ability to focus the X-ray beam on the sample down to microns,” said NSLS-II scientist and co-author Masa Fukuto. “By analyzing how these microbeam X-rays get scattered by the material, we learn about the material’s local structure at the illuminated spot. Measurements at many different spots can then reveal how the local structure varies across the gradient sample. In this work, we let the AI algorithm pick, on the fly, which spot to measure next to maximize the value of each measurement.”
As the sample was measured at the SMI beamline, the algorithm, without human intervention, created of model of the material’s numerous and diverse set of structures. The model updated itself with each subsequent X-ray measurement, making every measurement more insightful and accurate.
In a matter of hours, the algorithm had identified three key areas in the complex sample for the CFN researchers to study more closely. They used the CFN electron microscopy facility to image those key areas in exquisite detail, uncovering the rails and rungs of a nanoscale ladder, among other novel features.
From start to finish, the experiment ran about six hours. The researchers estimate they would have needed about a month to make this discovery using traditional methods.
Calvin: “Sometimes I think the surest sign that Intelligent Life exists elsewhere in the Universe is that so far …. None of it has tried to contact us!”
“Autonomous methods can tremendously accelerate discovery,” Yager said. “It’s essentially ‘tightening’ the usual discovery loop of science, so that we cycle between hypotheses and measurements more quickly. Beyond just speed, however, autonomous methods increase the scope of what we can study, meaning we can tackle more challenging science problems.”
“Moving forward, we want to investigate the complex interplay among multiple parameters. We conducted simulations using the CFN computer cluster that verified our experimental results, but they also suggested how other parameters, such as film thickness, can also play an important role,” Doerk said.
The team is actively applying their autonomous research method to even more challenging material discovery problems in self-assembly, as well as other classes of materials. Autonomous discovery methods are adaptable and can be applied to nearly any research problem.
“We are now deploying these methods to the broad community of users who come to CFN and NSLS-II to conduct experiments,” Yager said. “Anyone can work with us to accelerate the exploration of their materials research. We foresee this empowering a host of new discoveries in the coming years, including in national priority areas like clean energy and microelectronics.”
Source Nano Mag
DNA Nanotechnology Tools: From Design to Applications: Current Opportunities and Collaborations – Wyss Institute – Harvard University
- DNA as building blocks
- Broad applications
- Low cost with big potential
DNA nanostructures with their potential for cell and tissue permeability, biocompatibility, and high programmability at the nanoscale level are promising candidates as new types of drug delivery vehicles, highly specific diagnostic devices, and tools to decipher how biomolecules dynamically change their shapes, and interact with each other and with candidate drugs. Wyss Institute researchers are providing a suite of diverse, multifunctional DNA nanotechnological tools with unique capabilities and potential for a broad range of clinical and biomedical research areas.
DNA nanotechnological devices for therapeutic drug delivery
DNA nanostructures have future potential to be widely used to transport and present a variety of biologically active molecules such as drugs and immune-enhancing antigens and adjuvants to target cells and tissues in the human body.
DNA origami as high-precision delivery components of cancer vaccines
The Wyss Institute has developed cancer vaccines to improve immunotherapies. These approaches use implantable or injectable biomaterial-based scaffolds that present tumor-specific antigens, and biomolecules that attract dendritic immune cells (DCs) into the scaffold, and activate them so that after their release they can orchestrate anti-tumor T cell responses against tumors carrying the same antigens. To be activated most effectively, DCs likely need to experience tumor antigens and immune-boosting CpG adjuvant molecules at particular ratios (stoichiometries) and configurations that register with the density and distribution of receptor molecules on their cell surface.
Specifically developed DNA origami, programmed to assemble into rigid square-lattice blocks that co-present tumor antigens and adjuvants to DCs within biomaterial scaffolds with nanoscale precision have the potential to boost the efficacy of therapeutic cancer vaccines, and can be further functionalized with anti-cancer drugs.
Chemical modification strategy to protect drug-delivering DNA nanostructures
DNA nanostructures such as self-assembling DNA origami are promising vehicles for the delivery of drugs and diagnostics. They can be flexibly functionalized with small molecule and protein drugs, as well as features that facilitate their delivery to specific target cells and tissues. However, their potential is hampered by their limited stability in the body’s tissues and blood. To help fulfill the extraordinary promise of DNA nanostructures, Wyss researchers developed an easy, effective and scalable chemical cross-linking approach that can provide DNA nanostructures with the stability they need as effective vehicles for drugs and diagnostics.
In two simple cost-effective steps, the Wyss’ approach first uses a small-molecule, unobtrusive neutralizing agent, PEG-oligolysine, that carries multiple positive charges, to cover DNA origami structures. In contrast to commonly used Mg2+ions that each neutralize only two negative changes in DNA structures, PEG-oligolysine covers multiple negative charges at one, thus forming a stable “electrostatic net,” which increases the stability of DNA nanostructures about 400-fold. Then, by applying a chemical cross-linking reagent known as glutaraldehyde, additional stabilizing bonds are introduced into the electrostatic net, which increases the stability of DNA nanostructures by another 250-fold, extending their half-life into a range that is compatible with a broad range of clinical applications.
DNA nanotechnological devices as ultrasensitive diagnostic and analytical tools
The generation of detectable DNA nanostructures in response to a disease or pathogen-specific nucleic acids, in principle, offers a means for highly effective biomarker detection in diverse samples. A single molecule binding event of a synthetic oligonucleotide to a target nucleic acid can nucleate the creation of much larger structures by the cooperative assembly of smaller synthetic DNA units like DNA tiles or bricks into larger structures that then can be visualized in simple laboratory assays. However, a central obstacle to these approaches is the occurrence of (1) non-specific binding and (2) non-specific nucleation events in the absence of a specific target nucleic acid which can lead to false-positive results. Wyss DNA nanotechnologists have developed two separately applicable but combinable solutions for these problems.
Digital counting of biomarker molecules with DNA nanoswitch catenanes
To enable the initial detection (binding) of biomarkers with ultra-high sensitivity and specificity, Wyss researchers have developed a type of DNA nanoswitch that, designed as a larger catenane (Latin catenameaning chain), is assembled from mechanically interlocked ring-shaped substructures with specific functionalities that together enable the detection and counting of single biomarker molecules. In the “DNA Nanoswitch Catenane” structure, both ends of a longer synthetic DNA strand are linked to two antibody fragments that each specifically bind different parts of the same biomarker molecule of interest, thus allowing for high target specificity and sensitivity.
This bridging-event causes the strand to close into a “host ring,” which it is interlocked at different regions with different “guest rings.” Closing of the host ring switches the guest rings into a configuration that allows the synthesis of a new DNA strand. The newly synthesized diagnostic strand then can be unambiguously detected as a single digital molecule count, while disrupting the antibody fragment/biomarker complex starts a new biomarker counting cycle. Both, the target binding specificity and the synthesis of a target-specific DNA strand also enable the combination of multiple DNA nanoswitch catenanes to simultaneously count different biomarker molecules in a single multiplexed reaction.
For ultrasensitive diagnostics, it is desirable to have the fastest amplification and the lowest rate of spurious nucleation. DNA nanotechnology approaches have the potential to deliver this in an enzyme-free, low-cost manner.
A rapid amplification platform for diverse biomarkers
A rapid, low-cost and enzyme-free detection and amplification platform avoids non-specific nucleation and amplification and allows the self-assembly of much larger micron-scale structures from a single seed in just minutes. The method, called “Crisscross Nanoseed Detection” enables the ultra-cooperative assembly of ribbons starting from a single biomarker binding event. The micron-scale structures are densely woven from single-stranded “DNA slats,” whereby an inbound slat snakes over and under six or more previously captured slats on a growing ribbon end in a “crisscross” manner, forming weak but highly-specific interactions with its interacting DNA slats. The nucleation of the assembly process is strictly target-seed specific and the assembly can be carried out in a one-step reaction in about 15 minutes without the addition of further reagents, and over a broad range of temperatures. Using standard laboratory equipment, the assembled structures then can be rapidly visualized or otherwise detected, for example, using high-throughput fluorescence plate reader assays.
CURRENT OPPORTUNITY – STARTUP
Crisscross Nanoseed Detection: Nanotechnology-Powered Infectious Disease Diagnostics
Enzyme-free DNA nanotechnology for rapid, ultrasensitive, and low-cost detection of infectious disease biomarkers with broad accessibility in point-of-care settings.
The DNA assembly process in the Crisscross Nanoseed Detection method can also be linked to the action of DNA nanoswitch catenanes that highly specifically detect a biomarker molecule leading to preservation of a molecular record. Each surviving record can nucleate the assembly of a crisscross nanostructure, combining high-specificity binding with amplification for biomarker detection.
Wyss researchers are currently developing the approach as a multiplexable low-cost diagnostic for the COVID-19 causing SARS-CoV-2 virus and other pathogens that could give accurate results faster and at lower costs than currently used techniques.
Nanoscale devices for determining the structure and identity of proteins at the single-molecule level
The ability to identify and quantify proteins from trace biological samples would have a profound impact on both basic research and clinical practice, from monitoring changes in protein expression within individual cells, to enabling the discovery of new biomarkers of disease. Furthermore, the ability to also determine their structures and interactions would open up new avenues for drug discovery and characterization. Over the past decades, developments in DNA analysis and sequencing have unquestionably revolutionized medicine – yet equivalent developments for protein analysis have remained a challenge. While methods such as mass spectrometry for protein identification, and cryoEM for structure determination have rapidly advanced, challenges remain regarding resolution and the ability to work with trace heterogeneous samples.
To help meet this challenge, researchers at the Wyss Institute have developed a new approach that combines DNA nanotechnology with single-molecule manipulation to enable the structural identification and analysis of proteins and other macromolecules. “DNA Nanoswitch Calipers” (DNCs) offer a high-resolution approach to “fingerprint proteins” by measuring distances and determining geometries within single proteins in solution. DNCs are nanodevices designed to measure distances between DNA handles that have been attached to target molecules of interest. DNC states can be actuated and read out using single-molecule force spectroscopy, enabling multiple absolute distance measurements to be made on each single-molecule.
DNCs could be widely adapted to advance research in different areas, including structural biology, proteomics, diagnostics and drug discovery.
All technologies are in development and available for industry collaborations.
Nanoplastics unexpectedly produce reactive oxidizing species when exposed to light
Plastics are ubiquitous in our society, found in packaging and bottles as well as making up more than 18% of solid waste in landfills. Many of these plastics also make their way into the oceans, where they take up to hundreds of years to break down into pieces that can harm wildlife and the aquatic ecosystem.
A team of researchers, led by Young-Shin Jun, Professor of Energy, Environmental & Chemical Engineering in the McKelvey School of Engineering at Washington University in St. Louis, analyzed how light breaks down polystyrene, a nonbiodegradable plastic from which packing peanuts, DVD cases and disposable utensils are made. In addition, they found that nanoplastic particles can play active roles in environmental systems. In particular, when exposed to light, the nanoplastics derived from polystyrene unexpectedly facilitated the oxidation of aqueous manganese ions and the formation of manganese oxide solids that can affect the fate and transport of organic contaminants in natural and engineering water systems.
The research, published in ACS Nanoon Dec. 27, 2022, showed how the photochemical reaction of nanoplastics through light absorption generates peroxyl and superoxide radicals on nanoplastic surfaces, and initiates oxidation of manganese into manganese oxide solids.
“As more plastic debris accumulates in the natural environment, there are increasing concerns about its adverse effects,” said Jun, who leads the Environmental Nanochemistry Laboratory. “However, in most cases, we have been concerned about the roles of the physical presence of nanoplastics rather than their active roles as reactants. We found that such small plastic particles that can more easily interact with neighboring substances, such as heavy metals and organic contaminants, and can be more reactive than we previously thought.”
Jun and her former student, Zhenwei Gao, who earned a doctorate in environmental engineering at WashU in 2022 and is now a postdoctoral scholar at the University of Chicago, experimentally demonstrated that the different surface functional groups on polystyrene nanoplastics affected manganese oxidation rates by influencing the generation of the highly reactive radicals, peroxyl and superoxide radicals. The production of these reactive oxygen species from nanoplastics can endanger marine life and human health and potentially affects the mobility of the nanoplastics in the environment via redox reactions, which in turn might negatively impact their environmental remediation.
The team also looked at the size effects of polystyrene nanoplastics on manganese oxidation, using 30 nanometer, 100 nanometer and 500 nanometer particles. The two larger-sized nanoparticles took longer to oxidize manganese than the smaller particles. Eventually, the nanoplastics will be surrounded by newly formed manganese oxide fibers, which can make them easily aggregated and can change their reactivities and transport.
“The smaller particle size of the polystyrene nanoplastics may more easily decompose and release organic matter because of their larger surface area,” Jun said. “This dissolved organic matter may quickly produce reactive oxygen species in light and facilitate manganese oxidation.”
“This experimental work also provides useful insights into the heterogeneous nucleation and growth of manganese oxide solids on such organic substrates, which benefits our understanding of manganese oxide occurrences in the environment and engineered materials syntheses,” Jun said. “These manganese solids are excellent scavengers of redox-active species and heavy metals, further affecting geochemical element redox cycling, carbon mineralization and biological metabolisms in nature.”
Jun’s team plans to study the breakdown of diverse common plastic sources that can release nanoplastics and reactive oxidizing species and to investigate their active roles in the oxidation of transition and heavy metal ions in the future.null
More information: Zhenwei Gao et al, Oxidative Roles of Polystyrene-Based Nanoplastics in Inducing Manganese Oxide Formation under Light Illumination, ACS Nano (2022). DOI: 10.1021/acsnano.2c05803
Journal information: ACS Nano
Provided by Washington University in St. Louis
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