chemistry (63)

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An X-ray flash illuminates a molecule. Credit: Raphael Jay

Topics: Chemistry, Climate Change, Green Tech, High Energy Physics, Research, X-rays

The use of short flashes of X-ray light brings scientists one big step closer to developing better catalysts to transform the greenhouse gas methane into a less harmful chemical. The result, published in the journal Science, reveals for the first time how carbon-hydrogen bonds of alkanes break and how the catalyst works in this reaction.

Methane, one of the most potent greenhouse gases, is being released into the atmosphere at an increasing rate by livestock farming and the unfreezing of permafrost. Transforming methane and longer-chain alkanes into less harmful and, in fact, useful chemicals would remove the associated threats and, in turn, make a huge feedstock for the chemical industry available. However, transforming methane necessitates, as a first step, the breaking of a C-H bond, one of the strongest chemical linkages in nature.

Forty years ago, molecular metal catalysts that can easily split C-H bonds were discovered. The only thing found to be necessary was a short flash of visible light to "switch on" the catalyst, and, as by magic, the strong C-H bonds of alkanes passing nearby are easily broken almost without using any energy. Despite the importance of this so-called C-H activation reaction, it remained unknown over the decades how that catalyst performs this function.

The research was led by scientists from Uppsala University in collaboration with the Paul Scherrer Institute in Switzerland, Stockholm University, Hamburg University, and the European XFEL in Germany. For the first time, the scientists were able to directly watch the catalyst at work and reveal how it breaks those C-H bonds.

In two experiments conducted at the Paul Scherrer Institute in Switzerland, the researchers were able to follow the delicate exchange of electrons between a rhodium catalyst and an octane C-H group as it gets broken. Using two of the most powerful sources of X-ray flashes in the world, the X-ray laser SwissFEL and the X-ray synchrotron Swiss Light Source, the reaction could be followed all the way from the beginning to the end. The measurements revealed the initial light-induced activation of the catalyst within 400 femtoseconds (0.0000000000004 seconds) to the final C-H bond breaking after 14 nanoseconds (0.000000014 seconds).

X-rays visualize how one of nature's strongest bonds breaks, Uppsala University, Phys.org.

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Organic Solar Cells...

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Prof. Li Gang invented a novel technique to achieve breakthrough efficiency with organic solar cells. Credit: Hong Kong Polytechnic University

Topics: Chemistry, Green Tech, Materials Science, Photonics, Research, Solar Power

Researchers from The Hong Kong Polytechnic University (PolyU) have achieved a breakthrough power-conversion efficiency (PCE) of 19.31% with organic solar cells (OSCs), also known as polymer solar cells. This remarkable binary OSC efficiency will help enhance these advanced solar energy device applications.

The PCE, a measure of the power generated from a given solar irradiation, is considered a significant benchmark for the performance of photovoltaics (PVs), or solar panels, in power generation. The improved efficiency of more than 19% that was achieved by the PolyU researchers constitutes a record for binary OSCs, which have one donor and one acceptor in the photoactive layer.

Led by Prof. Li Gang, Chair Professor of Energy Conversion Technology, and Sir Sze-Yen Chung, Endowed Professor in Renewable Energy at PolyU, the research team invented a novel OSC morphology-regulating technique by using 1,3,5-trichlorobenzene as a crystallization regulator. This new technique boosts OSC efficiency and stability.

The team developed a non-monotonic intermediated state manipulation (ISM) strategy to manipulate the bulk-heterojunction (BHJ) OSC morphology and simultaneously optimize the crystallization dynamics and energy loss of non-fullerene OSCs. Unlike the strategy of using traditional solvent additives, which is based on excessive molecular aggregation in films, the ISM strategy promotes the formation of more ordered molecular stacking and favorable molecular aggregation. As a result, the PCE was considerably increased, and the undesirable non-radiative recombination loss was reduced. Notably, non-radiative recombination lowers the light generation efficiency and increases heat loss.

Researchers achieve a record 19.31% efficiency with organic solar cells. Hong Kong Polytechnic University. Tech Explore

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Nano Sanitizer...

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The disinfectant powder is stirred in bacteria-contaminated water (upper left). The mixture is exposed to sunlight, which rapidly kills all the bacteria (upper right). A magnet collects the metallic powder after disinfection (lower right). The powder is then reloaded into another beaker of contaminated water, and the disinfection process is repeated (lower left). (Image credit: Tong Wu/Stanford University)

Topics: Biology, Chemistry, Environment, Materials Science, Nanotechnology

When exposed to sunlight, a low-cost, recyclable powder can kill thousands of waterborne bacteria per second. Stanford and SLAC scientists say the ultrafast disinfectant could be a revolutionary advance for 2 billion people worldwide without access to safe drinking water.

At least 2 billion people worldwide routinely drink water contaminated with disease-causing microbes.

Now, scientists at Stanford University and SLAC National Accelerator Laboratory have invented a low-cost, recyclable powder that kills thousands of waterborne bacteria per second when exposed to ordinary sunlight. According to the Stanford and SLAC team, the discovery of this ultrafast disinfectant could be a significant advance for nearly 30 percent of the world’s population with no access to safe drinking water. Their results are published in a May 18 study in Nature Water.

“Waterborne diseases are responsible for 2 million deaths annually, the majority in children under the age of 5,” said study co-lead author Tong Wu, a former postdoctoral scholar of materials science and engineering (MSE) at the Stanford School of Engineering. “We believe that our novel technology will facilitate revolutionary changes in water disinfection and inspire more innovations in this exciting interdisciplinary field.”

Conventional water-treatment technologies include chemicals, which can produce toxic byproducts, and ultraviolet light, which takes a relatively long time to disinfect and requires a source of electricity.

The new disinfectant developed at Stanford is a harmless metallic powder that works by absorbing both UV and high-energy visible light from the sun. The powder consists of nano-size flakes of aluminum oxide, molybdenum sulfide, copper, and iron oxide.

“We only used a tiny amount of these materials,” said senior author Yi Cui, the Fortinet Founders Professor of MSE and of Energy Science & Engineering in the Stanford Doerr School of Sustainability. “The materials are low cost and fairly abundant. The key innovation is that, when immersed in water, they all function together.”

New nontoxic powder uses sunlight to quickly disinfect contaminated drinking water, Mark Shwartz, Stanford News.

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A Charge for all Seasons...

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The new composition for fluorine-containing electrolytes promises to maintain high battery charging performance for future electric vehicles even at sub-zero temperatures. (Image by Shutterstock.)

Topics: Battery, Chemistry, Climate Change, Global Warming, Lithium, Materials Science

Scientists developed a new and safer electrolyte for lithium-ion batteries that work as well in sub-zero conditions as it does at room temperature.

Many owners of electric vehicles worry about how effective their batteries will be in very cold weather. Now new battery chemistry may have solved that problem.

In current lithium-ion batteries, the main problem lies in the liquid electrolyte. This key battery component transfers charge-carrying particles called ions between the battery’s two electrodes, causing the battery to charge and discharge. But the liquid begins to freeze at sub-zero temperatures. This condition severely limits the effectiveness of charging electric vehicles in cold regions and seasons.

To address that problem, a team of scientists from the U.S. Department of Energy’s (DOE) Argonne and Lawrence Berkeley national laboratories developed a fluorine-containing electrolyte that performs well even in sub-zero temperatures.

“Our research thus demonstrated how to tailor the atomic structure of electrolyte solvents to design new electrolytes for sub-zero temperatures.” — John Zhang, Argonne group leader.

“Our team not only found an antifreeze electrolyte whose charging performance does not decline at minus 4 degrees Fahrenheit, but we also discovered, at the atomic level, what makes it so effective,” said Zhengcheng ​“John” Zhang, a senior chemist and group leader in Argonne’s Chemical Sciences and Engineering division.

This low-temperature electrolyte shows promise of working for batteries in electric vehicles, as well as in energy storage for electric grids and consumer electronics like computers and phones.

An electric vehicle battery for all seasons, Joseph E. Harmon, Argonne National Labs

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TEG...

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The new self-powered thermoelectric generator device uses an ultra-broadband solar absorber (UBSA) to capture sunlight, which heats the generator. Simultaneously, another component called a planar radiative cooling emitter (RCE) cools part of the device by releasing heat. Credit: Haoyuan Cai, Jimei University

Topics: Alternate Energy, Battery, Chemistry, Energy, Materials Science, Thermodynamics

Researchers have developed a new thermoelectric generator (TEG) that can continuously generate electricity using heat from the sun and a radiative element that releases heat into the air. Because it works during the day or night and in cloudy conditions, the new self-powered TEG could provide a reliable power source for small electronic devices such as outdoor sensors.

"Traditional power sources like batteries are limited in capacity and require regular replacement or recharging, which can be inconvenient and unsustainable," said research team leader Jing Liu from Jimei University in China. "Our new TEG design could offer a sustainable and continuous energy solution for small devices, addressing the constraints of traditional power sources like batteries."

TEGs are solid-state devices that use temperature differences to generate electricity without moving parts. In the journal Optics Express, Liu and a multi-institutional team of researchers describe and demonstrate a new TEG that can simultaneously generate the heat and cold necessary to create a temperature difference large enough to generate electricity even when the sun isn't out. The passive power source is made of components that can easily be manufactured.

"The unique design of our self-powered thermoelectric generator allows it to work continuously, no matter the weather," said Liu. "With further development, our TEG has the potential to impact a wide range of applications, from remote sensors to wearable electronics, promoting a more sustainable and eco-friendly approach to powering our daily lives."

New passive device continuously generates electricity during the day or night, Optica/Tech Explore

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Strange Metals II...

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Credit: CC0 Public Domain

Topics: Applied Physics, Chemistry, Materials Science, Metamaterials, Quantum Mechanics

The behavior of so-called "strange metals" has long puzzled scientists—but a group of researchers at the University of Toronto may be one step closer to understanding these materials.

Electrons are discrete, subatomic particles that flow through wires like molecules of water flowing through a pipe. The flow is known as electricity, and it is harnessed to power and control everything from lightbulbs to the Large Hadron Collider.

In quantum matter, by contrast, electrons don't behave as they do in normal materials. They are much stronger, and the four fundamental properties of electrons—charge, spin, orbit, and lattice—become intertwined, resulting in complex states of matter.

"In quantum matter, electrons shed their particle-like character and exhibit strange collective behavior," says condensed matter physicist Arun Paramekanti, a professor in the U of T's Department of Physics in the Faculty of Arts & Science. "These materials are known as non-Fermi liquids, in which the simple rules break down."

Now, three researchers from the university's Department of Physics and Centre for Quantum Information & Quantum Control (CQIQC) have developed a theoretical model describing the interactions between subatomic particles in non-Fermi liquids. The framework expands on existing models and will help researchers understand the behavior of these "strange metals."

Their research was published in the journal Proceedings of the National Academy of Sciences (PNAS). The lead author is physics Ph.D. student Andrew Hardy, with co-authors Paramekanti and post-doctoral researcher Arijit Haldar.

"We know that the flow of a complex fluid like blood through arteries is much harder to understand than water through pipes," says Paramekanti. "Similarly, the flow of electrons in non-Fermi liquids is much harder to study than that in simple metals."

Hardy adds, "What we've done is construct a model, a tool, to study non-Fermi liquid behavior. And specifically, to deal with what happens when there is symmetry breaking, when there is a phase transition into a new type of system."

"Symmetry breaking" is the term used to describe a fundamental process found in all of nature. Symmetry breaks when a system—whether a droplet of water or the entire universe—loses its symmetry and homogeneity and becomes more complex.

Researchers develop new insight into the enigmatic realm of 'strange metals', Chris Sasaki, University of Toronto, Phys.org

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Green Transition...

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Photo: Getty Images

Topics: Battery, Chemistry, Climate Change, Economics, Global Warming

Welcome back to The Green Era, a weekly newsletter bringing you the news and trends in the world of sustainability. Click subscribe above to be notified of future editions.

The shift to renewable energy has caused consternation over the fate of workers in the fossil fuel industry. Those same concerns are hitting the automotive sector as U.S. demand for electric vehicles grows.

EVs require not just new assembly lines and parts but also factories to build the batteries that power them. The president of one of the biggest unions called the transition the largest in the industry’s history.

The automotive sector and its workers are not new to factory closures. The Great Recession brought the big three automakers to their knees, forcing the federal government to bail them out, leaving cities like Detroit and large swaths of the midwest with car workers out of a job.

This time could be different. Many factories are being converted and are investing in retraining their workers. The batteries and charging infrastructure required present another opportunity. Ford, General Motors, and Volkswagen are all building new battery manufacturing plants or expanding existing ones in Tennessee.

The EV transition is changing workers’ skills and state economies, Jordyn Dahl, LinkedIn

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Catalysis and Energy Savings…

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Credit: Pixabay/CC0 Public Domain

Topics: Chemistry, Computer Modeling, Environment, Materials Science

In an advance, they consider a breakthrough in computational chemistry research. University of Wisconsin–Madison chemical engineers have developed a model of how catalytic reactions work at the atomic scale. This understanding could allow engineers and chemists to develop more efficient catalysts and tune industrial processes—potentially with enormous energy savings, given that 90% of the products we encounter in our lives are produced, at least partially, via catalysis.

Catalyst materials accelerate chemical reactions without undergoing changes themselves. They are critical for refining petroleum products and for manufacturing pharmaceuticals, plastics, food additives, fertilizers, green fuels, industrial chemicals, and much more.

Scientists and engineers have spent decades fine-tuning catalytic reactions—yet because it's currently impossible to directly observe those reactions at the extreme temperatures and pressures often involved in industrial-scale catalysis, they haven't known exactly what is taking place on the nano and atomic scales. This new research helps unravel that mystery with potentially major ramifications for the industry.

In fact, just three catalytic reactions—steam-methane reforming to produce hydrogen, ammonia synthesis to produce fertilizer, and methanol synthesis—use close to 10% of the world's energy.

"If you decrease the temperatures at which you have to run these reactions by only a few degrees, there will be an enormous decrease in the energy demand that we face as humanity today," says Manos Mavrikakis, a professor of chemical and biological engineering at UW–Madison who led the research. "By decreasing the energy needed to run all these processes, you are also decreasing their environmental footprint."

New atomic-scale understanding of catalysis could unlock massive energy savings, Jason Daley, University of Madison-Wisconson

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Zombie CFCs...

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Researchers detected a surprising rise in levels of chlorofluorocarbons between 2010 and 2020 using a monitoring network that includes the Jungfraujoch research station in Switzerland. Credit: Shutterstock

 Topics: Chemistry, Civilization, Climate Change, Environment, Global Warming

From my resume: "I eliminated ozone-depleting materials using Failure Mode and Effects Analysis (FMEA) and Taguchi Methods of Quality Engineering - using an L16 Orthogonal Array - in the Poly Silicon etch substituting out CFCs in manufacturing processes." How I did it: I substituted our CFC with Sulfur Hexafluoride and Nitrogen (SF6/N2). On the negative photoresist product, the CFC over-etch was 50 seconds. For the positive photoresist, CFC had a 25-second process. I was able to reduce each product line to two seconds, increasing throughput, and the process increased die yields. It is possible to balance the positive impact of product improvement and the environment. I did it in the 90s, so the following report is disappointing.

*****

The Montreal Protocol, which banned most uses of ozone-destroying chemicals known as chlorofluorocarbons (CFCs) and called for their global phase-out by 2010, has been a great success story: Earth’s ozone layer is projected to recover by the 2060s.

So atmospheric chemists were surprised to see a troubling signal in recent data. They found that the levels of five CFCs rose rapidly in the atmosphere from 2010 to 2020. Their results are published today in Nature Geoscience1.

“This shouldn’t be happening,” says Martin Vollmer, an atmospheric chemist at the Swiss Federal Laboratories for Materials Science and Technology in Dübendorf, who helped to analyze data from an international network of CFC monitors. “We expect the opposite trend. We expect them to slowly go down.”

At current levels, these CFCs do not pose much threat to the ozone layer’s healing, said Luke Western, a chemist at the University of Bristol, UK, at an online press conference on 30 March. CFCs, once used as refrigerants and aerosols, can persist in the atmosphere for hundreds of years. Given that they are potent greenhouse gases, eliminating emissions of these CFCs will also have a positive impact on Earth’s climate. The collective annual warming effect of these five chemicals on the planet is equivalent to the emissions produced by a small country like Switzerland.

It’s highly likely that manufacturing plants are accidentally releasing three of the chemicals — CFC-113a, CFC-114a, and CFC-115 — while producing replacements for CFCs. When CFCs were phased out, hydrofluorocarbons (HFCs) were brought in as substitutes. But CFCs can crop up as unintended by-products during HFC manufacture. This accidental production is discouraged by the Montreal Protocol but not prohibited by it.

‘This shouldn’t be happening: levels of banned CFCs rising, Katherine Bourzac, Nature

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Green Homing...

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Divine light The Dean of Gloucester Cathedral, Stephen Lake, blesses the cathedral’s solar panels after the solar-energy firm MyPower installed them in November 2016. The array of PV panels generates just over 25% of the building’s electricity. (Courtesy: MyPower)

Topics: Alternate Energy, Applied Physics, Battery, Chemistry, Economics, Solar Power

With energy bills on the rise, plenty of people are interested in ditching the fossil fuels currently used to heat most UK homes. The question is how to make it happen, as Margaret Harris explains.

Deep beneath the flagstones of the medieval Bath Abbey church, a modern marvel with an ancient twist is silently making its presence felt. Completed in March 2021, the abbey’s heating system combines underfloor pipes with heat exchangers located seven meters below the surface. There, a drain built nearly 2000 years ago carries 1.1 million liters of 40 °C water every day from a natural hot spring into a complex of ancient Roman baths.

By tapping into this flow of warm water, the system provides enough energy to heat not only the abbey but also an adjacent row of Georgian cottages used for offices. No wonder the abbey’s rector praised it as “a sustainable solution for heating our beautiful historic church.”

But that wasn’t all. Once efforts to decarbonize the abbey’s heating were underway, officials in the £19.4m Bath Abbey Footprint project turned their attention to the building’s electricity. Like most churches, the abbey runs from east to west, giving its roof an extensive south-facing aspect. At the UK’s northerly latitudes, such roofs are bathed in sunlight for much of the day, making them ideal for solar photovoltaic (PV) panels. Gloucester Cathedral – an hour’s drive north of Bath – has already taken advantage of this favorable orientation, becoming – in 2016 – the UK’s first major ancient cathedral to have solar panels installed on its roof.

To find out if a similar set-up might be suitable at Bath Abbey, the Footprint project worked with Ph.D. students in the University of Bath-led Centre for Doctoral Training (CDT) in New and Sustainable Photovoltaics. In a feasibility study published in Energy Science & Engineering (2022 10 892), the students calculated that a well-designed array of PV panels could supply 35.7% of the abbey’s electricity, plus 4.6% that could be sold back to the grid on days when a surplus was generated. The array would pay for itself within about 13 years and generate a total profit of £139,000 ± £12,000 over its 25-year lifetime.

Home, green home: scientific solutions for cutting carbon and (maybe) saving money, Margaret Harris, Physics World

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Scanning With a Twist...

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How it works: illustration of the quantum twisting microscope in action. Electrons tunnel from the probe (inverted pyramid at the top) to the sample (bottom) in several places at once (green vertical lines) in a quantum-coherent manner. (Courtesy: Weizmann Institute of Science)

Topics: Chemistry, Entanglement, Materials Science, Nanotechnology, Quantum Mechanics

When the scanning tunneling microscope debuted in the 1980s, the result was an explosion in nanotechnology and quantum-device research. Since then, other types of scanning probe microscopes have been developed, and together they have helped researchers flesh out theories of electron transport. But these techniques probe electrons at a single point, thereby observing them as particles and only seeing their wave nature indirectly. Now, researchers at the Weizmann Institute of Science in Israel have built a new scanning probe – the quantum twisting microscope – that detects the quantum wave characteristics of electrons directly.

“It’s effectively a scanning probe tip with an interferometer at its apex,” says Shahal Ilani, the team leader. The researchers overlay a scanning probe tip with ultrathin graphite, hexagonal boron nitride, and a van der Waals crystal such as graphene, which conveniently flopped over the tip like a tent with a flat top about 200 nm across. The flat end is key to the device’s interferometer function.  Instead of an electron tunneling between one point in the sample and the tip, the electron wave function can tunnel across multiple points simultaneously.

“Quite surprisingly, we found that the flat end naturally pivots so that it is always parallel with the sample,” says John Birkbeck, the corresponding author of a paper describing this work. This is fortunate because any tilt would alter the tunneling distance and hence strength from one side of the plateau to the other. “It is the interference of these tunneling paths, as identified in the measured current, that gives the device its unique quantum-wave probing function,” says Birkbeck.

Scanning probe with a twist observes the electron’s wavelike behavior, Anna Demming, Physics World

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Like Mushrooms for Plastics...

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Credit: VTT Technical Research Centre of Finland

Topics: Biology, Biotechnology, Chemistry, Materials Science, Mechanical Engineering

A research group from VTT Technical Research Center of Finland has unlocked the secret behind the extraordinary mechanical properties and ultra-light weight of certain fungi. The complex architectural design of mushrooms could be mimicked and used to create new materials to replace plastics. The research results were published on February 22, 2023, in Science Advances.

VTT's research shows for the first time the complex structural, chemical, and mechanical features adapted throughout the course of evolution by Hoof mushroom (Fomes fomentarius). These features interplay synergistically to create a completely new class of high-performance materials.

Research findings can be used as a source of inspiration to grow from the bottom up the next generation of mechanically robust and lightweight, sustainable materials for various applications under laboratory conditions. These include impact-resistant implants, sports equipment, body armor, and exoskeletons for aircraft, electronics, or windshield surface coatings.

Mushrooms could help replace plastics in new high-performance ultra-light materials, VTT Technical Research Centre of Finland, Phys.org.

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Graphullerene...

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Credit: Nicoletta Barolini

Topics: Chemistry, Graphene, Materials Science, Modern Physics, Nanotechnology

Graphullerene, an atom-thin material made of linked fullerene subunits, gives scientists a new form of modular carbon to play with.

Carbon, in its myriad forms, has long captivated the scientific community. Besides being the primary component of all organic life on earth, material forms of carbon have earned their fair share of breakthroughs. In 1996, the Nobel Prize in Chemistry went to the discoverers of fullerene, a superatomic symmetrical structure of 60 carbon atoms shaped like a soccer ball; in 2010, researchers working with an ultra-strong, atom-thin version of carbon, known as graphene, won the Nobel Prize in Physics.

Today in work published in Nature, researchers led by Columbia chemists Xavier Roy, Colin Nuckolls, and Michael Steigerwald, with postdoc and first author Elena Meirzadeh have discovered a new version of carbon that sits somewhere in between fullerene and graphene: graphullerene. It’s a new two-dimensional form of carbon made up of layers of linked fullerenes peeled into ultrathin flakes from a larger graphullerite crystal—just like how graphene is peeled from graphite crystals (the same material found in pencils).

“It is amazing to find a new form of carbon,” said Nuckolls. “It also makes you realize that there is a whole family of materials that can be made in a similar way that will have new and unusual properties as a consequence of the information written into the superatomic building blocks.”

Columbia Chemists Discover a New Form of Carbon: Graphene’s “Superatomic” Cousin, Ellen Neff, Quantum.Columbia.edu

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Chip Act and Wave Surfing...

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Massive subsidies to regain the edge of the US semiconductor industry will not likely succeed unless progress is made in winning the global race of idea flow and monetization.

Topics: Applied Physics, Chemistry, Computer Science, Electrical Engineering, Semiconductor Technology

Intelligent use of subsidies for winning the global idea race is a must for gaining and regaining semiconductor edge.

The US semiconductor industry started with the invention of Bell Labs. Subsequently, it attained supremacy in semiconductor production due to the success of making computers better and cheaper. Notably, the rise of the PC wave made Intel and Silicon Valley seemingly unsinkable technology superpowers. But during the first two decades of the 21st century, America has lost it. The USA now relies on Asia to import the most advanced chips. Its iconic Intel is now a couple of technology generation behind Asia’s TSMC and Samsung.

Furthermore, China’s aggressive move has added momentum to America’s despair, triggering a chip war. But why has America lost the edge? Why does it rely on TSMC and Samsung to supply the most advanced chips to power iPhones, Data centers, and Weapons? Is it due to Asian Governments’ subsidies? Or is it due to America’s failure to understand dynamics, make prudent decisions and manage technology and innovation?

Invention and rise and fall of US semiconductor supremacy

In 1947, Bell Labs of the USA invented a semiconductor device—the Transistor. Although American companies developed prototypes of Transistor radios and other consumer electronic products, they did not immediately pursue them. But American firms were very fast in using the Transistor to reinvent computers—by changing the vacuum tube technology core. Due to weight advantage, US Airforce and NASA found transistors suitable for onboard computers. Besides, the invention of integrated circuits by Fairchild and Texas instruments accelerated the weight and size reduction of digital logic circuits. Consequentially, the use of semiconductors in building onboard computers kept exponentially growing. Hence, by the end of the 1960s, the US had become a powerhouse in logic circuit semiconductors. But America remained 2nd to Japan in global production, as Japanese companies were winning the race of consumer electronics by using transistors.

US Semiconductor–from invention, supremacy to despair, Rokon Zaman, The-Waves.org

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CEM and SEI...

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Panel A shows how the native SEI on Li metal is passivating to nitrogen, which means that no reactivity with Li metal is possible. Panel B shows that a proton donor like Ethanol will disrupt the SEI passivation and enable Li metal to react with nitrogen species. Panel C describes 3 potential mechanisms through which the proton donor can disrupt the SEI passivation. Credit: Steinberg et al.

Topics: Applied Physics, Battery, Chemistry, Climate Change, Environment

Ammonia (NH3), the chemical compound made of nitrogen and hydrogen, currently has many valuable uses, for instance, serving as a crop fertilizer, purifying agent, and refrigerant gas. In recent years, scientists have been exploring its potential as an energy carrier to reduce global carbon emissions and help tackle global warming.

Ammonia is produced via the Haber-Bosch process, a carbon-producing industrial chemical reaction that converts nitrogen and hydrogen into NH3. As this process is known to contribute heavily to global carbon emissions, electrifying ammonia synthesis would benefit our planet.

One of the most promising strategies for electrically synthesizing ammonia at ambient conditions is using lithium metal. However, some aspects of these processes, including the properties and role of lithium's passivation layer, known as the solid electrolyte interphase (SEI), remain poorly understood.

Researchers at the Massachusetts Institute of Technology (MIT), the University of California- Los Angeles (UCLA), and the California Institute of Technology have recently conducted a study closely examining the reactivity of lithium and its SEI, as this could enhance lithium-based pathways to electrically synthesize ammonia. Their observations, published in Nature Energy, were collected using a state-of-the-art imaging method known as cryogenic transmission electron microscopy.

Using cryogenic electron microscopy to study the lithium SEI during electrocatalysis, Ingrid Fadelli, Phys.org

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OPVs...

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V. ALTOUNIAN/SCIENCE

Topics: Alternate Energy, Applied Physics, Chemistry, Materials Science, Solar Power

As ultrathin organic solar cells hit new efficiency records, researchers see green energy potential in surprising places.

In November 2021, while the municipal utility in Marburg, Germany, was performing scheduled maintenance on a hot water storage facility, engineers glued 18 solar panels to the outside of the main 10-meter-high cylindrical tank. It’s not the typical home for solar panels, most of which are flat, rigid silicon and glass rectangles arrayed on rooftops or in solar parks. The Marburg facility’s panels, by contrast, are ultrathin organic films made by Heliatek, a German solar company. In the past few years, Heliatek has mounted its flexible panels on the sides of office towers, the curved roofs of bus stops, and even the cylindrical shaft of an 80-meter-tall windmill. The goal: expanding solar power’s reach beyond flat land. “There is a huge market where classical photovoltaics do not work,” says Jan Birnstock, Heliatek’s chief technical officer.

Organic photovoltaics (OPVs) such as Heliatek’s are more than 10 times lighter than silicon panels and in some cases cost just half as much to produce. Some are even transparent, which has architects envisioning solar panels, not just on rooftops, but incorporated into building facades, windows, and even indoor spaces. “We want to change every building into an electricity-generating building,” Birnstock says.

Heliatek’s panels are among the few OPVs in practical use, and they convert about 9% of the energy in sunlight to electricity. But in recent years, researchers around the globe have come up with new materials and designs that, in small, lab-made prototypes, have reached efficiencies of nearly 20%, approaching silicon and alternative inorganic thin-film solar cells, such as those made from a mix of copper, indium, gallium, and selenium (CIGS). Unlike silicon crystals and CIGS, where researchers are mostly limited to the few chemical options nature gives them, OPVs allow them to tweak bonds, rearrange atoms, and mix in elements from across the periodic table. Those changes represent knobs chemists can adjust to improve their materials’ ability to absorb sunlight, conduct charges, and resist degradation. OPVs still fall short of those measures. But, “There is an enormous white space for exploration,” says Stephen Forrest, an OPV chemist at the University of Michigan, Ann Arbor.

Solar Energy Gets Flexible, Robert F. Service, Science Magazine

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The Nobel Prize in Chemistry 2022...

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Topics: Chemistry, Nobel Laureate, Nobel Prize

The Nobel Prize in Chemistry 2022 was awarded jointly to Carolyn R. Bertozzi, Morten Meldal, and K. Barry Sharpless "for the development of click chemistry and bioorthogonal chemistry"

The 2022 Nobel Prize in Chemistry is about making the difficult simple. Barry Sharpless and Morten Meldal have laid the foundations for a functional form of chemistry – click chemistry – where molecular building blocks quickly and efficiently snap into each other. Carolyn Bertozzi has taken click chemistry to a new dimension and brought it into living organisms.

Chemists have long been driven by the desire to be able to build increasingly complicated molecules. In pharmaceutical research, it has often been about being able to artificially recreate natural molecules that have healing properties. This has led to many admirable molecular constructions, which unfortunately are also generally time-consuming and very expensive to produce.

- This year's chemistry prize is about not fussing about it so much and instead starting from the easy and simple. Even if you choose a simple route, you can build advanced and useful molecules, says Johan Åqvist, chairman of the Nobel Committee for Chemistry.

Source: https://www.kva.se/nyheter/nobelpriset-i-kemi-2022/

The Nobel Prize in Chemistry 2022. NobelPrize.org. Nobel Prize Outreach AB 2022. Wed. 5 Oct 2022. < https://www.nobelprize.org/prizes/chemistry/2022/summary/ >

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5 Elements...

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(Credit: concept w/Shutterstock)

Topics: Chemistry, Nobel Laureate, Nobel Prize

Currently, there are 118 elements on the periodic table. If a new element is discovered, naming it involves several factors. Elements can be named after how they were obtained, their attributes, the compound they were isolated from, and places they were discovered. However, they can also be named after the people who found them. Fifteen elements have been named after scientists — here are five of them.

1. Curium (Cm)

2. Fermium (Fm)

3. Meitnerium (Mt)

4. Nobelium (No)

5. Oganesson (Og)

5 Elements Named in Honor of Notable Scientists, Allison Futterman, Discovery Magazine

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WASP-39b and CO2...

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Researchers detected carbon dioxide in WASP-39b’s atmosphere when the exoplanet crossed in front of its star. The data plot shows a telltale blip where infrared wavelengths from the star’s light were absorbed by carbon dioxide on the exoplanet. Credit: NASA, ESA, CSA, Leah Hustak (STScI), Joseph Olmsted (STScI)

Topics: Astrophysics, Chemistry, ESA, Exoplanets, James Webb Space Telescope, NASA

The James Webb Space Telescope — already famous for its mesmerizing images of the cosmos — has done it again. The telescope has captured the first unambiguous evidence of carbon dioxide in the atmosphere of a planet outside the Solar System.

The finding not only provides tantalizing hints about how the exoplanet formed but is also a harbinger for what’s to come as Webb studies more and more alien worlds. It was reported in a manuscript posted on the preprint server arXiv1, ahead of peer review, and is expected to be published in Nature in the coming days. (Nature’s news team is independent of its journals team.)

The discovery is presented in a data plot with none of the luster of Webb’s previous images — which showed galaxies locked in a cosmic dance and radiant clouds in a stellar nursery. But Jessie Christiansen, an astronomer at the NASA Exoplanet Science Institute at the California Institute of Technology in Pasadena, describes the data as “gorgeous”.

The plot, or spectrum, reveals detailed information about the atmosphere of the exoplanet WASP-39b, called a hot Jupiter by scientists because it has a diameter similar to Jupiter’s but orbits its star much more closely than Mercury orbits the Sun, making it incredibly hot. The planet, which is more than 200 parsecs from Earth, was initially discovered during ground-based observations2 and later detected by NASA’s Spitzer Space Telescope, which operated between 2003 and 2020. Data from the latter suggested3 that WASP-39b’s atmosphere might contain carbon dioxide, but they were inconclusive.

Webb telescope spots CO2 on exoplanet for first time: what it means for finding alien life, Sharron Hall, Nature

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Perovskite and Maxima...

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The effective mass of the electrons can be derived from the curvature around the maxima of the ARPES measurement data (image, detail). (Courtesy: HZB)

Topics: Alternate Energy, Applied Physics, Battery, Chemistry, Civilization, Climate Change

A longstanding explanation for why perovskite materials make such good solar cells has been cast into doubt thanks to new measurements. Previously, physicists ascribed the favorable optoelectronic properties of lead halide perovskites to the behavior of quasiparticles called polarons within the material’s crystal lattice. Now, however, detailed experiments at Germany’s BESSY II synchrotron revealed that no large polarons are present. The work sheds fresh light on how perovskites can be optimized for real-world applications, including light-emitting diodes, semiconductor lasers, and radiation detectors as well as solar cells.

Lead halide perovskites belong to a family of crystalline materials with an ABXstructure, where A is cesium, methylammonium (MA), or formamidinium (FA); B is lead or tin; and X is chlorine, bromine, or iodine. They are promising candidates for thin-film solar cells and other optoelectronic devices because their tuneable bandgaps enable them to absorb light over a broad range of wavelengths in the solar spectrum. Charge carriers (electrons and holes) also diffuse through them over long distances. These excellent properties give perovskite solar cells a power conversion efficiency of more than 18%, placing them on a par with established solar-cell materials such as silicon, gallium arsenide, and cadmium telluride.

Researchers are still unsure, however, exactly why charge carriers travel so well in perovskites, especially since perovskites contain far more defects than established solar-cell materials. One hypothesis is that polarons – composite particles made up of an electron surrounded by a cloud of ionic phonons, or lattice vibrations – act as screens, preventing charge carriers from interacting with the defects.

Charge-transport mystery deepens in promising solar-cell materials, Isabelle Dumé, Physics World

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