Science
How a Record-Breaking Copper Catalyst Converts CO2 Into Liquid Fuels
Researchers at Berkeley Lab have made real-time movies of copper nanoparticles as they evolve to convert carbon dioxide and water into renewable fuels and chemicals. Their new insights could help advance the next generation of solar fuels
Video of a 4D-STEM experiment: Berkeley Lab researchers used a new electrochemical liquid cell to observe copper nanoparticles (ranging in size from 7 nanometers to 18 nanometers) evolve into active nanograins during CO2 electrolysis – a process that uses electricity to drive a reaction on the surface of an electrocatalyst. The new electrochemical liquid cell allows researchers to resolve images of objects smaller than 10 nanometers.
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Newswise — Since the 1970s, scientists have known that copper has a special ability to transform carbon dioxide into valuable chemicals and fuels. But for many years, scientists have struggled to understand how this common metal works as an electrocatalyst, a mechanism that uses energy from electrons to chemically transform molecules into different products.
Now, a research team led by Lawrence Berkeley National Laboratory (Berkeley Lab) has gained new insight by capturing real-time movies of copper nanoparticles (copper particles engineered at the scale of a billionth of a meter) as they convert CO2 and water into renewable fuels and chemicals: ethylene, ethanol, and propanol, among others. The work was reported in the journal Nature last week.
“This is very exciting. After decades of work, we’re finally able to show – with undeniable proof – how copper electrocatalysts excel in CO2 reduction,” said Peidong Yang, a senior faculty scientist in Berkeley Lab’s Materials Sciences and Chemical Sciences Divisions who led the study. Yang is also a professor of chemistry and materials science and engineering at UC Berkeley. “Knowing how copper is such an excellent electrocatalyst brings us steps closer to turning CO2 into new, renewable solar fuels through artificial photosynthesis.”
The work was made possible by combining a new imaging technique called operando 4D electrochemical liquid-cell STEM (scanning transmission electron microscopy) with a soft X-ray probe to investigate the same sample environment: copper nanoparticles in liquid. First author Yao Yang, a UC Berkeley Miller postdoctoral fellow, conceived the groundbreaking approach under the guidance of Peidong Yang while working toward his Ph.D. in chemistry at Cornell University.
Credit: Thor Swift/Berkeley Lab
(From left to right): Julian Feijoo, Jianbo Jin, Cheng Wang, Peidong Yang, Yao Yang, Inwhan Roh, and Maria Fonseca Guzman at the Advanced Light Source.
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Artist’s rendering of a copper nanoparticle as it evolves during CO2 electrolysis: Copper nanoparticles (left) combine into larger metallic copper “nanograins” (right) within seconds of the electrochemical reaction, reducing CO2 into new multicarbon products.
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Credit: Thor Swift/Berkeley Lab
Yao Yang (center) loads a sample into the soft X-ray scattering chamber as Cheng Wang (left) and Peidong Yang (right) observe at the RSoXS Beamline (Beamline 11.0.1.2) at the Advanced Light Source.
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Scientists who study artificial photosynthesis materials and reactions have wanted to combine the power of an electron probe with X-rays, but the two techniques typically can’t be performed by the same instrument.
Electron microscopes (such as STEM or TEM) use beams of electrons and excel at characterizing the atomic structure in parts of a material. In recent years, 4D STEM (or “2D raster of 2D diffraction patterns using scanning transmission electron microscopy”) instruments, such as those at Berkeley Lab’s Molecular Foundry, have pushed the boundaries of electron microscopy even further, enabling scientists to map out atomic or molecular regions in a variety of materials, from hard metallic glass to soft, flexible films.
On the other hand, soft (or lower-energy) X-rays are useful for identifying and tracking chemical reactions in real time in an operando, or real-world, environment.
But now, scientists can have the best of both worlds. At the heart of the new technique is an electrochemical “liquid cell” sample holder with remarkable versatility. A thousand times thinner than a human hair, the device is compatible with both STEM and X-ray instruments.
The electrochemical liquid cell’s ultrathin design allows reliable imaging of delicate samples while protecting them from electron beam damage. A special electrode custom-designed by co-author Cheng Wang, a staff scientist at Berkeley Lab’s Advanced Light Source, enabled the team to conduct X-ray experiments with the electrochemical liquid cell. Combining the two allows researchers to comprehensively characterize electrochemical reactions in real time and at the nanoscale.
Getting granular
During 4D-STEM experiments, Yao Yang and team used the new electrochemical liquid cell to observe copper nanoparticles (ranging in size from 7 nanometers to 18 nanometers) evolve into active nanograins during CO2 electrolysis – a process that uses electricity to drive a reaction on the surface of an electrocatalyst.
The experiments revealed a surprise: copper nanoparticles combined into larger metallic copper “nanograins” within seconds of the electrochemical reaction.
To learn more, the team turned to Wang, who pioneered a technique known as “resonant soft X-ray scattering (RSoXS) for soft materials,” at the Advanced Light Source more than 10 years ago.
With help from Wang, the research team used the same electrochemical liquid cell, but this time during RSoXS experiments, to determine whether copper nanograins facilitate CO2 reduction. Soft X-rays are ideal for studying how copper electrocatalysts evolve during CO2 reduction, Wang explained. By using RSoXS, researchers can monitor multiple reactions between thousands of nanoparticles in real time, and accurately identify chemical reactants and products.
The RSoXS experiments at the Advanced Light Source – along with additional evidence gathered at Cornell High Energy Synchrotron Source (CHESS) – proved that metallic copper nanograins serve as active sites for CO2 reduction. (Metallic copper, also known as copper(0), is a form of the element copper.)
During CO2 electrolysis, the copper nanoparticles change their structure during a process called “electrochemical scrambling.” The copper nanoparticles’ surface layer of oxide degrades, creating open sites on the copper surface for CO2 molecules to attach, explained Peidong Yang. And as CO2 “docks” or binds to the copper nanograin surface, electrons are then transferred to CO2, causing a reaction that simultaneously produces ethylene, ethanol, and propanol along with other multicarbon products.
“The copper nanograins essentially turn into little chemical manufacturing factories,” Yao Yang said.
Further experiments at the Molecular Foundry, the Advanced Light Source, and CHESS revealed that size matters. All of the 7-nanometer copper nanoparticles participated in CO2 reduction, whereas the larger nanoparticles did not. In addition, the team learned that only metallic copper can efficiently reduce CO2 into multicarbon products. The findings have implications for “rationally designing efficient CO2 electrocatalysts,” Peidong Yang said.
The new study also validated Peidong Yang’s findings from 2017: That the 7-nanometer-sized copper nanoparticles require low inputs of energy to start CO2 reduction. As an electrocatalyst, the 7-nanometer copper nanoparticles required a record-low driving force that is about 300 millivolts less than typical bulk copper electrocatalysts. The best-performing catalysts that produce multicarbon products from CO2 typically operate at high driving force of 1 volt.
The copper nanograins could potentially boost the energy efficiency and productivity of some catalysts designed for artificial photosynthesis, a field of research that aims to produce solar fuels from sunlight, water, and CO2. Currently, researchers within the Department of Energy-funded Liquid Sunlight Alliance (LiSA) plan to use the copper nanograin catalysts in the design of future solar fuel devices.
“The technique’s ability to record real-time movies of a chemical process opens up exciting opportunities to study many other electrochemical energy conversion processes. It’s a huge breakthrough, and it would not have been possible without Yao and his pioneering work,” Peidong Yang said.
Researchers from Berkeley Lab, UC Berkeley, and Cornell University contributed to the work. Other authors on the paper include co-first authors Sheena Louisa and Sunmoon Yu, former UC Berkeley Ph.D. students in Peidong Yang’s group, along with Jianbo Jin, Inwhan Roh, Chubai Chen, Maria V. Fonseca Guzman, Julian Feijóo, Peng-Cheng Chen, Hongsen Wang, Christopher Pollock, Xin Huang, Yu-Tsuan Shao, Cheng Wang, David A. Muller, and Héctor D. Abruña.
Parts of the experiments were performed by Yao Yang at Cornell under the supervision of Héctor Abruña, professor of chemistry and chemical biology, and David A. Muller, professor of engineering.
This work was supported by the DOE Office of Science.
The Molecular Foundry and Advanced Light Source are user facilities at Berkeley Lab.
Source: Lawrence Berkeley National Laboratory
health and wellness
Lactose intolerance is actually the human norm – but racism, the US government and business interests have made it into a condition
Lactose intolerance is the global human norm, but Western dietary standards, government policies and commercial interests helped frame it as a medical deficiency.
Hilary Smith, University of Denver
Lactose intolerance makes drinking milk or eating ice cream a literal pain. For some people, eating a dairy treat can lead to bloating, nausea and diarrhea. You might’ve experienced its effects yourself. If so, you may think of lactose intolerance as a defect rather than the norm.
But did you know that most people in the world today are lactose intolerant – and that the condition itself was invented in the 1960s?
“Surely you mean discovered, not invented,” I hear you saying. I don’t. As a historian who has traced the origins of nutrition-science ideas, I have chosen the word “invented” on purpose.
Inventing lactose intolerance
Variations in people’s ability to digest lactose first came to scientists’ attention after American dairy producers found a way to rid themselves of a postwar milk surplus. To offload what they couldn’t sell, they looked to the government to intervene. And it did, buying the excess and embedding it in school lunches and other places with publicly funded meals.
Suddenly, many people who had not habitually drunk milk were consuming it regularly, including not only some Americans but also people overseas. Part of that same milk surplus found its way into school lunches in places such as Japan and Taiwan in the 1950s as the American government began to sell milk to allies during the Cold War.
Many of the groups drinking milk regularly for the first time did not like it. In fact, it made them feel sick. Intrigued, scientists set up experiments to figure out why. In a 1966 study comparing how Black and white people incarcerated in Baltimore metabolized lactose, researchers found that Black participants had lower levels of lactase – the enzyme that breaks down lactose – in their guts.
To the white scientists conducting this study, the trouble that the Black prisoners had digesting milk looked like an “inborn error of metabolism.” They assumed that the normal human state was lactose tolerance and that the lactose intolerant had inherited a genetic mutation.
It was only after years more work with research participants of many races that experts realized that, as one National Institutes of Health official put it in 1981, “lactose intolerance is a normal physiological condition, shared by every adult animal except for certain ethnic and racial groups in man.” People of northern European descent, it turned out, were the weird ones. It was their ancestors who had passed down a genetic mutation – one that made them able to digest milk after infancy.
In short, what scientists discovered in the 1960s was that different bodies process milk differently. What they invented was the idea that lactose intolerance is a defect. Accepting that framing would mean nearly two-thirds of the human population – the estimated prevalence of lactose intolerance worldwide – is defective.
Instead of acknowledging that dairy-free diets can be healthy, people innovated ways to overcome this supposed disability so everyone could consume more.
Nutritional imperialism
Lactose intolerance is one example of what I call nutritional imperialism: a way of thinking that treats white diets as the norm and everyone else’s as an aberration.
Nutritional imperialism was common in the 20th century, when scientists thought that not only milk-rich but also meat-heavy diets were best; they considered diets outside of the United States and Europe too vegetarian. Some also argued that wheat flour, not rice, ought to be the universal staple.
The same bias applied to bodies. Besides faulty lactose digestion, nonwhite bodies were accused of other failures, too, such as aldehyde dehydrogenase deficiency, an inability to digest alcohol quickly. The less technical term for this may be more familiar: Asian flush.
Such differences might have been thought of as variety, just another way of being human. Instead, each became a deficiency.
Many people today have inherited and perpetuated this way of thinking without knowing it, including those who are deemed deficient by it. In 1959, the director of Japan’s nutrition bureau declared that “rice-eating peoples” such as the Japanese were “resigned and passive” and could correct this by imitating Western diets and switching to wheat.
Today, the most prominent scientist promoting the idea that Asian flush is a disease is a geneticist of Taiwanese descent who started a research consortium to study “the most common human enzymopathy in the world.”
The Chinese Nutrition Society placed a tall glass of milk next to its 2022 Food Guide Plate – never mind estimates that the vast majority of Han Chinese, the largest ethnic group in China and worldwide, are lactose intolerant.
Turning sickness back into difference
Science that pathologizes difference helps racism persist.
In recent years, white supremacists have embraced the concept of lactose intolerance as a distinguishing debility of nonwhite people. Social media users have copied and pasted a map of the geographic distribution of lactose tolerance originally published in the scientific journal Nature into racist chat threads on the online discussion forum 4chan.
In 2017, internet trolls disrupted an anti-racist art installation with neo-Nazi chants and messily downed jugs of milk to accentuate their white identity.
Turning a lactose-digestion difference into a deficiency has done more to reinforce narratives of racial hierarchy than to improve public health. So here’s a suggestion: If you enjoy eating dairy, keep doing it; if you don’t, don’t – and know that there is nothing wrong with you.
Hilary Smith, Professor of History, University of Denver
This article is republished from The Conversation under a Creative Commons license. Read the original article.
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News
FAA Certifies Boeing 737-7: What It Means for Airlines and the 737 MAX Program
The FAA has certified Boeing’s new 737-7, clearing the smallest 737 MAX variant for service as Boeing and Southwest prepare for first deliveries.
The U.S. Federal Aviation Administration has certified Boeing’s new 737-7, granting the company an amended type certificate that clears the smallest member of the 737 MAX family for commercial service. The milestone closes a multi-year certification effort and puts the focus on execution: Boeing and launch customer Southwest Airlines say preparations are underway to support first deliveries.
For STM Daily News readers, the headline isn’t just “another plane gets approved.” It’s a signal that Boeing has now cleared a key MAX variant designed for long-range flexibility in a smaller footprint—an aircraft type airlines can use to open or defend routes where demand is strong, but not strong enough to justify a larger narrowbody.
What FAA certification means
An amended type certificate means the FAA has approved the 737-7’s design as compliant with commercial aviation regulations. In practical terms, certification allows airlines to place the aircraft into revenue service once deliveries begin and operator-specific steps—training, manuals, maintenance programs, and entry-into-service planning—are completed.
Boeing also said the FAA updated Boeing Production Certificate No. 700 (PC 700) to include the 737-7, supporting production and delivery activities.
Why the 737-7 matters in the MAX lineup
Boeing positions the 737-7 as the smallest and longest-range member of the 737 MAX family. The company says it typically seats 135 to 160 passengers in a two-class configuration and offers a range of up to 3,800 nautical miles (7,040 km). That combination matters because it gives airlines more options to fly longer “thin” routes—markets where frequency and reach matter more than packing in additional seats.
Boeing also highlights performance for operations out of high-altitude airports and in hot climates, where takeoff performance and payload-range tradeoffs can shape fleet decisions.
Efficiency claims: fuel, emissions, and noise
Boeing says the 737-7, like other 737 MAX jets, reduces fuel use and CO2 emissions by 20% and cuts the noise footprint by 50% compared to the airplanes it typically replaces. For airlines, those improvements typically show up in two ways:
- Route economics: lower fuel burn can improve margins on longer sectors and reduce exposure to fuel-price swings.
- Operational constraints: quieter aircraft can help with airport noise requirements and community pressure, while lower emissions support sustainability targets.
Inside the certification effort
Boeing said the certification program began in 2018 and included more than 1,000 hours of flight and ground testing, extensive system safety analysis, and human factors reviews. The company also noted an updated engine anti-ice system to address a potential condition discovered during flight testing.
Boeing Commercial Airplanes President and CEO Stephanie Pope called the certification “important” validation of the airplane’s design and the work of the MAX development team. Mike Sinnett, senior vice president of Product Strategy, Product Development and Development Programs, said Boeing held regular discussions with the FAA and that the process has sharpened the company’s understanding of current regulatory requirements—knowledge Boeing expects will accelerate future development with a renewed emphasis on human factors, safety, and quality.
What to watch next
With certification complete, the next phase is about delivery timing and real-world deployment.
- First deliveries to Southwest: Boeing and Southwest are preparing for delivery of the first airplane, including updates to final configuration.
- Production stability: certification removes a major hurdle, but supply chain health and production cadence will determine how quickly the 737-7 shows up in airline schedules.
- The 737-10 timeline: Boeing reiterated it is working to certify the 737-10 this year, keeping attention on how quickly the final MAX variant clears regulatory review.
The bigger MAX picture
Boeing said the 737 MAX family order book stands at more than 7,200 airplanes, with more than 2,300 delivered through the end of June 2026. The 737-7’s certification adds another deliverable product to that portfolio—one aimed at airlines that want long range without stepping up to a larger gauge.
Bottom line
FAA certification of the 737-7 is a meaningful milestone for Boeing and for airlines looking for a smaller narrowbody with long-range capability. The real test now is operational: turning certification into on-time deliveries and reliable entry into service—while the industry watches Boeing’s push to certify the 737-10.
Related Links
- Boeing 737 MAX family overview (manufacturer background/specs): https://www.boeing.com/commercial/737max/
- FAA Aircraft Certification (how type certification works): https://www.faa.gov/aircraft/air_cert/
- FAA Airworthiness Directives (regulatory actions database): https://www.faa.gov/regulations_policies/airworthiness_directives
- Southwest Airlines newsroom (launch customer context / fleet updates): https://www.swamedia.com/
- Boeing Commercial Airplanes newsroom (for follow-ups and official updates): https://boeing.mediaroom.com/news-releases?item=130821
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Source:
Boeing (PRNewswire), Aug. 3, 2026 — “U.S. FAA certifies new Boeing 737-7 airplane.”
Nature
What in the Heck Is a Sweat Bee? Turns Out, My Wife Wasn’t Making It Up
My wife Rebecca said she thought a sweat bee stung her. I thought she was making it up. Turns out, sweat bees are very real—and their strange name actually makes perfect sense.
It started with a conversation with my wife, Rebecca.
She mentioned that she thought she’d been stung by something called a “sweat bee.”
My immediate reaction was basically:
“What in the heck is a sweat bee?”
I’ll admit it. For a moment, I thought she was making the whole thing up. 😂
A sweat bee? Really?
It sounded like one of those names somebody invents when they don’t know what actually stung them.
“It wasn’t a regular bee. It was a… uh… sweat bee!”
So naturally, I asked ChatGPT the same question: What in the heck is a sweat bee?
Well, Rebecca gets this round.
Sweat bees are absolutely real.
And Yes, They’re Interested in Your Sweat
Sweat bees belong primarily to the Halictidae family, a large group of generally small bees found around the world.
Some are rather ordinary-looking little insects, while others are surprisingly flashy, sporting metallic shades of green, blue, bronze or gold.
But here’s where they earned that wonderfully unfortunate name.
Some sweat bees are attracted to human perspiration.
They’re not after you because they’re angry, and they’re certainly not tiny vampire bees. They’re interested in the salt and minerals in your sweat.
In other words, after you’ve been outside working, gardening, exercising or simply trying to survive a hot summer afternoon, a sweat bee may look at you and think:
“Hey! Free electrolytes!”
Wait…They Can Sting Too?
Unfortunately for Rebecca, there’s another part of her story that checks out.
Female sweat bees can sting.
They’re generally not aggressive and aren’t flying around looking for people to attack. But if one gets trapped against your skin, squeezed or swatted, it may defend itself.
Their sting is generally considered relatively mild compared with those of many other bees and wasps—but “relatively mild” probably isn’t much consolation when you’re the person who just got stung.
So, Rebecca, I officially withdraw my skepticism.
Mostly.
Don’t Declare War on Them
As annoying as having a tiny bee land on your sweaty arm might be, sweat bees are actually beneficial insects.
They’re important pollinators, visiting wildflowers, garden plants and agricultural crops and carrying pollen from flower to flower.
So if one lands on you, gently brushing or blowing it away is probably a better idea than swatting it against your skin.
And that’s today’s unexpected nature lesson.
Sweat bees are real.
They really are attracted to sweat.
The females really can sting.
And, perhaps most importantly…
My wife was right.
There. I said it.
I’m sure I’ll never hear the end of this one. 😂
Related Links
- University of Arizona Cooperative Extension — Arizona Bee Identification Guide — A useful Arizona-focused guide that includes sweat bees and explains their appearance, size, nesting behavior and attraction to salt in perspiration.
- USDA Natural Resources Conservation Service — Native Bees and Their Favorite Flowers — More information about native pollinators and the important role sweat bees play around wildflowers.
- USDA Forest Service — Bee Basics — A broader guide to North American bees, including the colorful metallic members of the sweat bee family.
- Smithsonian National Museum of Natural History — Sweat Bee — See an actual female sweat bee specimen (Augochlorella aurata) and its scientific classification.
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