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‘Goldene’ is a gilded cousin of graphene that is one atom thick

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An abstract computer illustration of a web of connected golden points of light.

Researchers have synthesized sheets of gold that are one atom thick.Credit: imaginima/Getty

Goldene is a cousin of graphene, the single-atom-thick sheet of carbon first discovered in 2004 — but made of gold. Goldene is roughly 400 times as thin as the thinnest commercial gold leaf, and might find use as a catalyst, or in light-sensing devices.

Nature | 4 min read

Reference: Nature Synthesis paper

GOLD MINING. Graphic shows the method researchers used to create goldene – a single layer of interconnected gold atoms.

Source: Adapted from Ref. 1.

Researchers in Canada are thrilled by “the largest investment in graduate students and postdocs in over 21 years”, says Kaitlin Kharas, a PhD student and executive director of the campaign group Support Our Science.

The 2024 Canadian federal budget gave:

• whopping increases to stipends for masters and PhD students and postgraduate researchers

• an extra Can$1.8 billion over five years in core funding for the three federal research councils

• more than Can$2 billion for the AI sector in Canada

Nature | 4 min read

The queens of some species of bumblebee can survive after being underwater for one week, which could help them withstand floods when they hibernate underground. An experimental accident revealed the possibility, and tests on 126 common eastern bumblebee (Bombus impatiens) queens confirmed that most can survive immersion for up to 7 days. The findings hint that other bee species could also have built-in flood resilience. “This seems to be one small aspect of climate change that we need not worry about,” says bee researcher Dave Goulson.

The Guardian | 4 min read

Reference: Biology Letters paper

Hundreds of artefacts sheltered by a lava-tube cave in what is now Saudi Arabia show that herders and their livestock used the cave on and off for the past 10,000 years. The region near the Umm Jirsan cave was once lush and green. Now, wind and scorching heat mean that, across the surface of Saudi Arabia, “the fossil record is just horrendous”, says zooarchaeologist and study co-author Mathew Stewart. But an 88,000-year-old finger bone described in 2018 — one of the oldest human fossils found outside Africa — hints at the region’s hidden history.

Nature | 4 min read

Reference: PLoS One paper

Four people standing in a tunnel with an arch-shaped roof made of basalt.

Inside the Umm Jirsan lava-tube cave, researchers have found evidence of human occupation dating back 10,000 years.Credit: Green Arabia Project

Features & opinion

During the pandemic, sewage provided a critical source of data for monitoring the spread of SARS-CoV-2. In Hong Kong, routine wastewater tests traced the virus to a single apartment block where no COVID had been reported — ultimately uncovering nine active cases. Now “every day, we come up with new things that we can interrogate wastewater for”, says public-health researcher Ted Smith — including signs of drug misuse, antimicrobial resistance and exposure to air pollution. Wastewater research coordinator Bernd Manfred Gawlik calls wastewater the “dirty blood of the city”, and compares sewage sampling to blood testing. “We are now only starting to understand” how to diagnose this “blood” at the collective level, he says.

Nature | 12 min read

Corporate lobbyists with vested interests in fossil fuels should be kept at arm’s length from negotiations for a global plastics treaty, writes ecotoxicologist Martin Wagner. The number of lobbyists from chemical and oil companies outnumbered scientists four to one in the previous round of talks. Their presence threatens to weaken the treaty by casting doubt on plastics research or demanding cumbersome risk assessments for individual component chemicals, says Wagner. Scientists also need better access to the talks for them to be meaningful, argues a Nature editorial.

Nature World View | 5 min read | & Nature Editorial | 5 min read

Countries are introducing some of the toughest restrictions ever on tobacco use and vaping — especially among young people. New laws in the United Kingdom, Australia and France could save thousands of lives and billions of dollars, say scientists. Many nations are banning disposable vapes that don’t contain tobacco but still deliver nicotine, which can raise blood pressure and disrupt brain development. “This policy push should see the upswing in youth vaping contained and reversed,” says epidemiologist Tony Blakely.

Nature | 6 min read

QUOTE OF THE DAY

In Kenya, this traditional adage reflects a modern reality: herders are replacing cattle with milk-producing camels to adapt to climate change. (The Washington Post | 12 min read)

Today we’re reeling from the sight of what is probably an ancient hominid jaw bone encased in a stone tile. A Reddit user, who’s also a dentist, spotted the mandible in his parents’ new travertine floor. This type of limestone often contains fossils, notes paleoanthropologist John Hawks. “This naturally raises a broader question: How many other people have installed travertine with hominin fossils inside?”

Let me know about what telltale hearts you’ve got hidden under the floorboards — plus any other feedback on this newsletter — at [email protected].

Thanks for reading,

Flora Graham, senior editor, Nature Briefing

With contributions by Gemma Conroy, Sarah Tomlin and Katharine Sanderson

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this gilded cousin of graphene is also one atom thick

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It is the world’s thinnest gold leaf: a gossamer sheet of gold just one atom thick. Researchers have synthesized1 the long-sought material, known as goldene, which is expected to capture light in ways that could be useful in applications such as sensing and catalysis.

Goldene is a gilded cousin of graphene, the iconic atom-thin material made of carbon that was discovered in 2004. Since then, scientists have identified hundreds more of these 2D materials. But it has been particularly difficult to produce 2D sheets of metals, because their atoms have always tended to cluster together to make nanoparticles instead.

Researchers have previously reported single-atom-thick layers of tin2 and lead3 stuck to various substances, and they have produced gold sheets sandwiched between other materials. But “we submit that goldene is the first free-standing 2D metal, to the best of our knowledge”, says materials scientist Lars Hultman at Linköping University in Sweden, who is part of the team behind the new research. Crucially, the simple chemical method used to make goldene should be amenable to larger-scale production, the researchers reported in Nature Synthesis on 16 April1.

“I’m very excited about it,” says Stephanie Reich, a solid-state physicist and materials scientist at the Free University of Berlin, who was not involved in the work. “People have been thinking for quite some time how to take traditional metals and make them into really well-ordered 2D monolayers.”

In 2022, researchers at New York University Abu Dhabi (NYUAD) said that they had produced goldene, but the Linköping team contends that the prior material probably contained multiple atomic layers, on the basis of the electron microscopy images and other data that were published in ACS Applied Materials and Interfaces4. Reich agrees that the 2022 study failed to prove that the material was singler-layer goldene. The principal authors of the NYUAD study did not respond to Nature’s questions about their work.

Golden age

To prepare goldene, the Linköping researchers started with a material containing atomic monolayers of silicon sandwiched between titanium carbide. When they added gold on top of this sandwich, it diffused into the structure and exchanged places with the silicon to create a trapped atom-thick layer of gold (see ‘Gold mining’). They then etched away the titanium carbide to release free-standing goldene sheets that were up to 100 nanometres wide, and roughly 400 times as thin as the thinnest commercial gold leaf, Hultman estimates.

GOLD MINING. Graphic shows the method researchers used to create goldene – a single layer of interconnected gold atoms.

Source: Adapted from Ref. 1.

That etching process used a solution of alkaline potassium ferricyanide known as Murukami’s reagent. “What’s so fascinating is that it’s a 100-year-old recipe used by Japanese smiths to decorate ironwork,” Hultman says. The researchers also added surfactant molecules — compounds that formed a protective barrier between goldene and the surrounding liquid — to stop the sheets from sticking together.

The Linköping team suggests that goldene might be useful in applications in which gold nanoparticles already show promise. Light can generate waves in the sea of electrons at a gold nanoparticle’s surface, which can channel and concentrate that energy. This strong response to light has been harnessed in gold photocatalysts to split water to produce hydrogen, for instance. Goldene could open up opportunities in areas such as this, Hultman says, but its properties need to be investigated in more detail first.

“I think the research is really interesting,” says Graham Hutchings, a chemist at the University of Cardiff, UK, who develops gold catalysts. But he worries that any residual traces of iron from Murukami’s reagent might hamper the development of goldene as a catalyst. “I would think that potential contamination with iron is going to cause a few problems in applications,” he says.

For now, the Linköping researchers are seeking better ways to sieve goldene from the solution used to make it, and to grow larger flakes of the material. They are also exploring whether their method can be used to make monolayers of other catalytic metals, including iridium, platinum and palladium.

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Weird new electron behaviour in stacked graphene thrills physicists

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Illustration showing four graphene layers.

Electrons in stacked sheets of staggered graphene collectively act as though they have fractional charges at ultra-low temperatures.Credit: Ramon Andrade 3DCiencia/Science Photo Library

Minneapolis, Minnesota

Last May, a team led by physicists at the University of Washington in Seattle observed something peculiar. When the scientists ran an electrical current across two atom-thin sheets of molybdenum ditelluride (MoTe2), the electrons acted in concert, like particles with fractional charges. Resistance measurements showed that, rather than the usual charge of –1, the electrons behaved similar to particles with charges of –2/3 or –3/5, for instance. What was truly odd was that the electrons did this entirely because of the innate properties of the material, without any external magnetic field coaxing them. The researchers published the results a few months later, in August1.

That same month, this phenomenon, known as the fractional quantum anomalous Hall effect (FQAHE), was also observed in a completely different material. A team led by Long Ju, a condensed-matter physicist at the Massachusetts Institute of Technology (MIT) in Cambridge, saw the effect when they sandwiched five layers of graphene between sheets of boron nitride. They published their results in February this year2 — and physicists are still buzzing about it.

At the American Physical Society (APS) March Meeting, held in Minneapolis, Minnesota, from 3 to 8 March, Ju presented the team’s findings, which haven’t yet been replicated by other researchers. Attendees, including Raquel Queiroz, a theoretical physicist at Columbia University in New York City, said that they thought the results were convincing, but were scratching their heads over the discovery. “There is a lot we don’t understand,” Queiroz says. Figuring out the exact mechanism of the FQAHE in the layered graphene will be “a lot of work ahead of theorists”, she adds.

Although the FQAHE might have practical applications down the line — fractionally charged particles are a key requirement for a certain type of quantum computer — the findings are capturing physicists’ imagination because they are fundamentally new discoveries about how electrons behave.

“I don’t know anyone who’s not excited about this,” says Pablo Jarillo-Herrero, a condensed-matter physicist at MIT who was not involved with the studies. “I think the question is whether you’re so excited that you switch all your research and start working on it, or if you’re just very excited.”

Strange maths

Strange behaviour by electrons isn’t new.

In some materials, usually at temperatures near absolute zero, electrical resistance becomes quantized. Specifically it’s the material’s transverse resistance that does this. (An electrical current encounters opposition to its flow in both the same direction as the current — called longitudinal resistance — and in the perpendicular direction — what’s called transverse resistance.)

Quantized ‘steps’ in the transverse resistance occur at multiples of electron charge: 1, 2, 3 and so on. These plateaus are the result of a strange phenomenon: the electrons maintain the same transverse resistance even as charge density increases. That’s a little like vehicles on a highway moving at the same speed, even with more traffic. This is known as the quantum Hall effect.

In a different set of materials, with less disorder, the transverse resistance can even display plateaus at fractions of electron charge: 2/5, 3/7 and 4/9, for example. The plateaus take these values because the electrons collectively act like particles with fractional charges — hence the fractional quantum Hall effect (FQHE).

Key to both phenomena is a strong external magnetic field, which prevents electrons from crashing into each other and enables them to interact.

A photo of the team. From left to right: Long Ju, Postdoc Zhengguang Lu, visiting undergraduate Yuxuan Yao, graduate student Tonghang Hang.

(Left to right) Long Ju, Zhengguang Lu, Yuxuan Yao and Tonghang Hang are all part of the team at MIT that demonstrated the FQAHE in layered graphene.Credit: Jixiang Yang

The FQHE, discovered in 1982, revealed the richness of electron behaviour. No longer could physicists think of electrons as single particles; in delicate quantum arrangements, the electrons could lose their individuality and act together to create fractionally charged particles. “I think people don’t appreciate how different [the fractional] is from the integer quantum Hall effect,” says Ashvin Vishwanath, a theoretical physicist at Harvard University in Cambridge. “It’s a new world.”

Over the next few decades, theoretical physicists came up with models to explain the FQHE and predict its effects. During their exploration, a tantalizing possibility appeared: perhaps a material could exhibit resistance plateaus without any external magnetic field. The effect, now dubbed the quantum anomalous Hall effect — ‘anomalous’, for the lack of a magnetic field — was finally observed in thin ferromagnetic films by a team at Tsinghua University in Beijing, in 20123.

Carbon copy

Roughly a decade later, the University of Washington team reported the FQAHE for the first time1, in a specially designed 2D material: two sheets of MoTe2 stacked on top of one another and offset by a twist.

This arrangement of MoTe2 is known as a moiré material. Originally used to refer to a patterned textile, the term has been appropriated by physicists to describe the patterns in 2D materials created from atom-thin lattices when they are stacked and then twisted, or staggered atop one another. The slight offset between atoms in different layers of the material shifts the hills and valleys of its electric potential. And it effectively acts like a powerful magnetic field, taking the place of the one needed in the quantum Hall effect and the FQHE.

Xiaodong Xu, a condensed-matter physicist at the University of Washington, talked about the MoTe2 discovery at the APS meeting. Theory hinted that the FQAHE would appear in the material at about a 1.4º twist angle. “We spent a year on it, and we didn’t see anything,” Xu told Nature.

Anomalous behaviour. Graphic showing the details of new moire material.

Source: Adapted from Ref. 2.

Then, the researchers tried a larger angle — a twist of about 4º. Immediately, they began seeing signs of the effect. Eventually, they measured the electrical resistance and spotted the signature plateaus of the FQAHE. Soon after, a team led by researchers at Shanghai Jiao Tong University in China replicated the results4.

Meanwhile at MIT, Ju was perfecting his technique, sandwiching graphene between layers of boron nitride. Similar to graphene, the sheets of boron nitride that Ju’s team used were a mesh of atoms linked together in a hexagonal pattern. Its lattice has a slightly different size than graphene; the mismatch creates a moiré pattern (see ‘Anomalous behaviour’).

Last month, Ju published a report2 about seeing the characteristic plateaus. “It is a really amazing result,” Xu says. “I’m very happy to see there’s a second system.” Since then, Ju says that he’s also seen the effect when using four and six layers of graphene.

Both moiré systems have their pros and cons. MoTe2 exhibited the effect at a few Kelvin, as opposed to 0.1 Kelvin for the layered graphene sandwich. (Low temperatures are required to minimize disorder in the systems.) But graphene is a cleaner and higher-quality material that is easier to measure. Experimentalists are now trying to replicate the results in graphene and find other materials that behave similarly.

Moiré than bargained for

Theorists are relatively comfortable with the MoTe2 results, for which the FQAHE was partly predicted. But Ju’s layered graphene moiré was a shock to the community, and researchers are still struggling to explain how the effect happens. “There’s no universal consensus on what the correct theory is,” Vishwanath says. “But they all agree that it’s not the standard mechanism.” Vishwanath and his colleagues posted a preprint proposing a theory that the moiré pattern might not be that important to the FQAHE5.

One reason to doubt the importance of the moiré is the location of the electrons in the material: most of the activity is in the topmost layer of graphene, far away from the moiré pattern between the graphene and boron nitride at the bottom of the sandwich that is supposed to most strongly influence the electrons. But B. Andrei Bernevig, a theoretical physicist at Princeton University in New Jersey, and a co-author of another preprint proposing a mechanism for the FQAHE in the layered graphene6, urges caution about theory-based calculations, because they rely on currently unverified assumptions. He says that the moiré pattern probably matters, but less than it does in MoTe2.

For theorists, the uncertainty is exciting. “There are people who would say that everything has been seen in the quantum Hall effect,” Vishwanath says. But these experiments, especially the one using the layered graphene moiré, show that there are still more mysteries to uncover.

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3M Thinsulate graphene heated vest with 5 zone intelligent heating

3M Thinsulate graphene heated vest with 5 zone intelligent heating

The Heatou graphene heated vest is ideal for cold weather activities featuring a professional-grade graphene shell. This shell gives the vest waterproof, windproof, and abrasion-resistant properties. It’s this graphene shell that ensures the vest can withstand the harshest of weather conditions, from biting winds to heavy downpours, while also resisting wear and tear from frequent use.

Inside this graphene shell, the vest is equipped with advanced carbon nanotube heating elements. Carbon nanotubes, known for their high thermal conductivity, are used here to provide consistent, efficient heating. These elements work in conjunction with 3M™ Featherless Thinsulate™ Insulation, a synthetic material designed to mimic the warming properties of down but with the added benefit of retaining heat even when wet. This combination of advanced materials results in a vest that provides consistent warmth, even in extremely cold conditions.

Despite its high-tech interior, the Heatou heated vest remains lightweight and breathable. The design is such that it doesn’t compromise on comfort or mobility, making it ideal for a range of activities, from casual walks to more strenuous outdoor pursuits.

One of the standout features of this vest is its individualized temperature control. This allows the wearer to adjust the heat to their comfort level, with three temperature settings available: 45℃ (GREEN), 55℃ (BLUE), and 65℃ (RED). This level of control ensures the wearer stays warm without overheating, providing a comfortable experience throughout. Early bird bargains are now available for the modern project from roughly $97 or £82 (depending on current exchange rates).

“Dislike the winter chill? Always grappling with bulky, unwieldy clothing that fails to keep you warm. It’s a constant source of frustration during outdoor activities. Heatou takes graphene-enhanced clothing to a whole new level of modern sustainability and style, surpassing the warmth of traditional synthetic insulation. Our vests are lightweight, versatile, durable, and breathable, ensuring comfort all year round.”

Powering this vest is a customized 10,000mAh power bank, which can be added when purchasing the product. This power bank ensures the vest’s heating elements can operate for extended periods, providing consistent warmth throughout the day. The effectiveness of the graphene heated vest is not diminished by wind speeds. Even in wind speeds of up to 50 miles/80 kilometers per hour, the vest’s graphene fabric technology performs effectively. This is a testament to the vest’s robust design and the exceptional properties of graphene.

Heatou 3M Thinsulate graphene heated vest

The vest’s carbon nanotube technology links its eight heating panels, providing higher thermal conductivity and speed, and achieving a conversion efficiency of over 95%. This high efficiency means that almost all the energy supplied to the vest is converted into heat, minimizing energy waste.

The heated vest eliminates the need for bulky layers. Thanks to the graphene layer and precise three-zone temperature control, the vest adjusts to the wearer’s sensations, providing the right amount of warmth as needed. This means that, even in cold weather, the wearer can maintain comfort and mobility without being encumbered by multiple layers of clothing.

The Heatou graphene heated vest is a cutting-edge piece of heated clothing that combines graphene technology, advanced heating elements, and top-quality insulation to provide consistent, adjustable warmth. Its robust design ensures it can withstand harsh weather conditions, while its lightweight and breathable nature ensures comfort. Whether for casual wear or outdoor activities, this vest is a versatile addition to any wardrobe.

Assuming that the Heatou funding campaign successfully raises its required pledge goal and the project completion progresses smoothly, worldwide shipping is expected to take place sometime around December 2023. To learn more about the Heatou 3M Thinsulate graphene heated vest project observe the promotional video below.

For a complete list of all available pledges, stretch goals, extra media and technical overview for the 3M Thinsulate graphene heated vest, jump over to the official Heatou crowd funding campaign page by navigating to the link below.

Source : Kickstarter

Disclaimer: Participating in Kickstarter campaigns involves inherent risks. While many projects successfully meet their goals, others may fail to deliver due to numerous challenges. Always conduct thorough research and exercise caution when pledging your hard-earned money.

Filed Under: Gadgets News, Top News





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UZE Graphene waterproof heated jacket with 4 heat zones

UZE Graphene waterproof heated jacket with 4 heat zones

UZE has once again taken to Kickstarter for its third crowdfunding campaign, which is already successfully blasted past its required pledge goal with still 26 days remaining. The companies latest innovation is the UZE Heated Jacket, designed for all four seasons, and equipped with four graphene heat zones and three different heat settings. All controllable from a single button positioned on the chest of the jacket.

Graphene, a single layer of carbon arranged in a two-dimensional honeycomb lattice, is renowned for its excellent thermal conductivity properties. UZE has harnessed this property to create a jacket that provides customizable warmth across four distinct zones. This feature, combined with three adjustable heat settings (mild, moderate, or intense), ensures that wearers can tailor their jacket’s heat to their comfort level. Early bird pledges are now available for the state-of-the-art project from roughly $349 or £287 (depending on current exchange rates).

UZE heated jacket heat pads

The UZE Heated Jacket is not just about warmth, it is also about adaptability. The jacket’s modular design allows wearers to customize their look and function. This flexibility extends to the jacket’s power source, the UZE Power Bank. This power bank not only provides up to 10 hours of heat but also charges 10 times faster than typical heated jacket power banks. This rapid charge feature ensures that users are never left out in the cold.

Heated jacket with 4 heat zones

UZE’s commitment to durability and versatility is evident in the construction of the UZE Heated Jacket. The jacket is made from UZEShield fabric, a material that is both water and windproof. This fabric remains touch dry even after heavy rainfall, reducing the need for consumers to purchase multiple jackets each year. This feature, combined with the jacket’s four-season design, makes the UZE Heated Jacket a practical investment for those looking to streamline their wardrobe.

UZE heated jacket design and styling

The UZE Heated Jacket’s design is not only functional but also user-friendly. The jacket features a magnetic closure system for easy fastening and pockets designed for easy access to essentials like bank cards, key cards, and ski passes. It even has dedicated slots for a fast-charging power bank, sunglasses, and a keychain holder. These features underscore UZE’s commitment to creating products that are as practical as they are innovative.

Assuming that the UZE funding campaign successfully raises its required pledge goal and production progresses smoothly, worldwide shipping is expected to take place sometime around December 2023. To learn more about the UZE Graphene waterproof heated jacket project preview the promotional video below.

Other articles we have written that you may find of interest on the subject of UZE products :

UZE Graphene waterproof jacket

The UZE Heated Jacket represents a significant step forward in the realm of wearable tech. Its innovative use of graphene heat zones, combined with its customizable heat settings and modular design, make it a versatile and practical addition to any wardrobe. Whether you’re an outdoor enthusiast looking for a durable, all-season jacket, or a tech-savvy consumer interested in the latest wearable tech, the UZE Heated Jacket is worth considering.

UZE heated jacket controls

For a complete list of all available pledges, stretch goals, extra media and functionality overview for the Graphene waterproof heated jacket, jump over to the official UZE crowd funding campaign page by navigating to the link below.

Source : Kickstarter

Disclaimer: Participating in Kickstarter campaigns involves inherent risks. While many projects successfully meet their goals, others may fail to deliver due to numerous challenges. Always conduct thorough research and exercise caution when pledging your hard-earned money.

Filed Under: Design News, Top News





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Disclosure: Some of our articles include affiliate links. If you buy something through one of these links, timeswonderful may earn an affiliate commission. Learn about our Disclosure Policy.