chemistry (60)

PV Caveats...

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 Graphical abstract. Credit: Joule (2024). DOI: 10.1016/j.joule.2024.01.025

Topics: Applied Physics, Chemistry, Energy, Green Tech, Materials Science, Photovoltaics

 

The energy transition is progressing, and photovoltaics (PV) is playing a key role in this. Enormous capacities are to be added over the next few decades. Experts expect several tens of terawatts by the middle of the century. That's 10 to 25 solar modules for every person. The boom will provide clean, green energy. But this growth also has its downsides.

 

Several million tons of waste from old modules are expected by 2050—and that's just for the European market. Even if today's PV modules are designed to last as long as possible, they will end up in landfill at the end of their life, and with them some valuable materials.

 

"Circular economy recycling in photovoltaics will be crucial to avoiding waste streams on a scale roughly equivalent to today's global electronic waste," explains physicist Dr. Marius Peters from the Helmholtz Institute Erlangen-Nürnberg for Renewable Energies (HI ERN), a branch of Forschungszentrum Jülich.

 

Today's solar modules are only suitable for this to a limited extent. The reason for this is the integrated—i.e., hardly separable—structure of the modules, which is a prerequisite for their long service life. Even though recycling is mandatory in the European Union, PV modules are, therefore, difficult to reuse in a circular way.

 

The current study by Dr. Ian Marius Peters, Dr. Jens Hauch, and Prof Christoph Brabec from HI ERN shows how important it is for the rapid growth of the PV industry to recycle these materials. "Our vision is to move away from a design for eternity towards a design for the eternal cycle," says Peters "This will make renewable energy more sustainable than any energy technology before.

 

The consequences of the PV boom: Study analyzes recycling strategies for solar modules, Forschungszentrum Juelich

 

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Plastics and Infarctions...

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Plastic chokes a canal in Chennai, India. Credit: R. Satish Babu/AFP via Getty

Topics: Applied Physics, Biology, Chemistry, Environment, Medicine

People who had tiny plastic particles lodged in a key blood vessel were more likely to experience heart attack, stroke or death during a three-year study.

Plastics are just about everywhere — food packaging, tyres, clothes, water pipes. And they shed microscopic particles that end up in the environment and can be ingested or inhaled by people.

Now, the first data of their kind show a link between these microplastics and human health. A study of more than 200 people undergoing surgery found that nearly 60% had microplastics or even smaller nanoplastics in a main artery1. Those who did were 4.5 times more likely to experience a heart attack, a stroke, or death in the approximately 34 months after the surgery than were those whose arteries were plastic-free.

“This is a landmark trial,” says Robert Brook, a physician-scientist at Wayne State University in Detroit, Michigan, who studies the environmental effects on cardiovascular health and was not involved with the study. “This will be the launching pad for further studies across the world to corroborate, extend, and delve into the degree of the risk that micro- and nanoplastics pose.”

But Brook, other researchers and the authors themselves caution that this study, published in The New England Journal of Medicine on 6 March, does not show that the tiny pieces caused poor health. Other factors that the researchers did not study, such as socio-economic status, could be driving ill health rather than the plastics themselves, they say.

Landmark study links microplastics to serious health problems, Max Kozlov, Nature.

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Recycling Green Plastics...

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Credit: Cell Reports Physical Science (2024). DOI: 10.1016/j.xcrp.2024.101783

Topics: Biochemistry, Chemistry, Polymer Science, Polymers

Scientists at King's College London have developed an innovative solution for recycling single-use bioplastics commonly used in disposable items such as coffee cups and food containers.

The novel method of chemical recycling, published in Cell Reports Physical Science, uses enzymes typically found in biological laundry detergents to "depolymerize"—or break down—landfill-bound bioplastics. Rapidly converting the items into soluble fragments within just 24 hours, the process achieves full degradation of the bioplastic polylactic acid (PLA). The approach is 84 times faster than the 12-week-long industrial composting process used for recycling bioplastic materials.

This discovery offers a widespread recycling solution for single-use PLA plastics, as the team of chemists at King's found that in a further 24 hours at a temperature of 90°C, the bioplastics break down into their chemical building blocks. Once converted into monomers—single molecules—the materials can be turned into equally high-quality plastic for multiple reuse.

The problem with 'green' plastics

Current rates of plastic production outstrip our ability to dispose of it sustainably. According to Environmental Action, it is estimated that in 2023 alone, more than 68 million tons of plastic globally ended up in natural environments due to the imbalance between the huge volumes of plastics produced and our current capacity to manage and recycle plastic at the end of its life. A recent OECD report predicted that the amount of plastic waste produced worldwide will almost triple by 2060, with around half ending up in landfills and less than a fifth recycled.

An enzyme used in laundry detergent can recycle single-use plastics within 24 hours, King's College London.

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Limit Shattered...

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TSMC is building Two New Facilities to Accommodate 2nm Chip Production

Topics: Applied Physics, Chemistry, Electrical Engineering, Materials Science, Nanoengineering, Semiconductor Technology

 

Realize that Moore’s “law” isn’t like Newton’s Laws of Gravity or the three laws of Thermodynamics. It’s simply an observation based on experience with manufacturing silicon processors and the desire to make money from the endeavor continually.

 

As a device engineer, I had heard “7 nm, and that’s it” so often that it became colloquial folklore. TSMC has proven itself a powerhouse once again and, in our faltering geopolitical climate, made itself even more desirable to mainland China in its quest to annex the island, sadly by force if necessary.

 

Apple will be the first electronic manufacturer to receive chips built by Taiwan Semiconductor Manufacturing Company (TSMC) using a two-nanometer process. According to Korea’s DigiTimes Asia, inside sources said that Apple is "widely believed to be the initial client to utilize the process." The report noted that TSMC has been increasing its production capacity in response to “significant customer orders.” Moreover, the report added that the company has recently established a production expansion strategy aimed at producing 2nm chipsets based on the Gate-all-around (GAA) manufacturing process.

 

The GAA process, also known as gate-all-around field-effect transistor (GAA-FET) technology, defies the performance limitations of other chip manufacturing processes by allowing the transistors to carry more current while staying relatively small in size.

 

Apple to jump queue for TSMC's industry-first 2-nanometer chips: Report, Harsh Shivam, New Delhi, Business Standard.

 

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Fast Charger...

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Significant Li plating capacity from Si anode. a, Li discharge profile in a battery of Li/graphite–Li5.5PS4.5Cl1.5 (LPSCl1.5)–LGPS–LPSCl1.5–SiG at current density 0.2 mA cm–2 at room temperature. Note that SiG was made by mixing Si and graphite in one composite layer. Inset shows the schematic illustration of stages 1–3 based on SEM and EDS mapping, which illustrate the unique Li–Si anode evolution in solid-state batteries observed experimentally in Figs. 1 and 2. b, FIB–SEM images of the SiG anode at different discharge states (i), (ii), and (iii) corresponding to points 1–3 in a, respectively. c, SEM–EDS mapping of (i), (ii), and (iii), corresponding to SEM images in b, where carbon signal (C) is derived from graphite, oxygen (O) and nitrogen (N) signals are from Li metal reaction with air and fluorine (F) is from the PTFE binder. d, Discharge profile of battery with cell construction Li-1M LiPF6 in EC/DMC–SiG. Schematics illustrate typical Si anode evolution in liquid-electrolyte batteries. e, FIB–SEM image (i) of SiG anode following discharge in the liquid-electrolyte battery shown in d; zoomed-in image (ii). Credit: Nature Materials (2024). DOI: 10.1038/s41563-023-01722-x

Topics: Applied Physics, Battery, Chemistry, Climate Change, Electrical Engineering, Mechanical Engineering

Researchers from the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have developed a new lithium metal battery that can be charged and discharged at least 6,000 times—more than any other pouch battery cell—and can be recharged in a matter of minutes.

The research not only describes a new way to make solid-state batteries with a lithium metal anode but also offers a new understanding of the materials used for these potentially revolutionary batteries.

The research is published in Nature Materials.

"Lithium metal anode batteries are considered the holy grail of batteries because they have ten times the capacity of commercial graphite anodes and could drastically increase the driving distance of electric vehicles," said Xin Li, Associate Professor of Materials Science at SEAS and senior author of the paper. "Our research is an important step toward more practical solid-state batteries for industrial and commercial applications."

One of the biggest challenges in the design of these batteries is the formation of dendrites on the surface of the anode. These structures grow like roots into the electrolyte and pierce the barrier separating the anode and cathode, causing the battery to short or even catch fire.

These dendrites form when lithium ions move from the cathode to the anode during charging, attaching to the surface of the anode in a process called plating. Plating on the anode creates an uneven, non-homogeneous surface, like plaque on teeth, and allows dendrites to take root. When discharged, that plaque-like coating needs to be stripped from the anode, and when plating is uneven, the stripping process can be slow and result in potholes that induce even more uneven plating in the next charge.

Solid-state battery design charges in minutes and lasts for thousands of cycles, Leah Burrows, Harvard John A. Paulson School of Engineering and Applied Sciences, Tech Xplore

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10x > Kevlar...

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Scientists have developed amorphous silicon carbide, a strong and scalable material with potential uses in microchip sensors, solar cells, and space exploration. This breakthrough promises significant advancements in material science and microchip technology. An artist’s impression of amorphous silicon carbide nanostrings testing to its limit tensile strength. Credit: Science Brush

Topics: Applied Physics, Chemistry, Materials Science, Nanomaterials, Semiconductor Technology

A new material that doesn’t just rival the strength of diamonds and graphene but boasts a yield strength ten times greater than Kevlar, renowned for its use in bulletproof vests.

Researchers at Delft University of Technology, led by assistant professor Richard Norte, have unveiled a remarkable new material with the potential to impact the world of material science: amorphous silicon carbide (a-SiC).

Beyond its exceptional strength, this material demonstrates mechanical properties crucial for vibration isolation on a microchip. Amorphous silicon carbide is particularly suitable for making ultra-sensitive microchip sensors.

The range of potential applications is vast, from ultra-sensitive microchip sensors and advanced solar cells to pioneering space exploration and DNA sequencing technologies. The advantages of this material’s strength, combined with its scalability, make it exceptionally promising.

Researchers at Delft University of Technology, led by assistant professor Richard Norte, have unveiled a remarkable new material with the potential to impact the world of material science: amorphous silicon carbide (a-SiC).

The researchers adopted an innovative method to test this material’s tensile strength. Instead of traditional methods that might introduce inaccuracies from how the material is anchored, they turned to microchip technology. By growing the films of amorphous silicon carbide on a silicon substrate and suspending them, they leveraged the geometry of the nanostrings to induce high tensile forces. By fabricating many such structures with increasing tensile forces, they meticulously observed the point of breakage. This microchip-based approach ensures unprecedented precision and paves the way for future material testing.

Why the focus on nanostrings? “Nanostrings are fundamental building blocks, the foundation that can be used to construct more intricate suspended structures. Demonstrating high yield strength in a nanostring translates to showcasing strength in its most elemental form.”

10x Stronger Than Kevlar: Amorphous Silicon Carbide Could Revolutionize Material Science, Delft University Of Technology

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Scandium and Superconductors...

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Scandium is the only known elemental superconductor to have a critical temperature in the 30 K range. This phase diagram shows the superconducting transition temperature (Tc) and crystal structure versus pressure for scandium. The measured results on all the five samples studied show consistent trends. (Courtesy: Chinese Phys. Lett. 40 107403)

Topics: Applied Physics, Chemistry, Condensed Matter Physics, Materials Science, Superconductors, Thermodynamics

Scandium remains a superconductor at temperatures above 30 K (-243.15 Celsius, -405.67 Fahrenheit), making it the first element known to superconduct at such a high temperature. The record-breaking discovery was made by researchers in China, Japan, and Canada, who subjected the element to pressures of up to 283 GPa – around 2.3 million times the atmospheric pressure at sea level.

Many materials become superconductors – that is, they conduct electricity without resistance – when cooled to low temperatures. The first superconductor to be discovered, for example, was solid mercury in 1911, and its transition temperature Tc is only a few degrees above absolute zero. Several other superconductors were discovered shortly afterward with similarly frosty values of Tc.

In the late 1950s, the Bardeen–Cooper–Schrieffer (BCS) theory explained this superconducting transition as the point at which electrons overcome their mutual electrical repulsion to form so-called “Cooper pairs” that then travel unhindered through the material. But beginning in the late 1980s, a new class of “high-temperature” superconductors emerged that could not be explained using BCS theory. These materials have Tc above the boiling point of liquid nitrogen (77 K), and they are not metals. Instead, they are insulators containing copper oxides (cuprates), and their existence suggests it might be possible to achieve superconductivity at even higher temperatures.

The search for room-temperature superconductors has been on ever since, as such materials would considerably improve the efficiency of electrical generators and transmission lines while also making common applications of superconductivity (including superconducting magnets in particle accelerators and medical devices like MRI scanners) simpler and cheaper.

Scandium breaks temperature record for elemental superconductors, Isabelle Dumé, Physics World

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Cooling Circuitry...

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Illustration of a UCLA-developed solid-state thermal transistor using an electric field to control heat movement. Credit: H-Lab/UCLA

Topics: Applied Physics, Battery, Chemistry, Electrical Engineering, Energy, Thermodynamics

A new thermal transistor can control heat as precisely as an electrical transistor can control electricity.

From smartphones to supercomputers, electronics have a heat problem. Modern computer chips suffer from microscopic “hotspots” with power density levels that exceed those of rocket nozzles and even approach that of the sun’s surface. Because of this, more than half the total electricity burned at U.S. data centers isn’t used for computing but for cooling. Many promising new technologies—such as 3-D-stacked chips and renewable energy systems—are blocked from reaching their full potential by errant heat that diminishes a device’s performance, reliability, and longevity.

“Heat is very challenging to manage,” says Yongjie Hu, a physicist and mechanical engineer at the University of California, Los Angeles. “Controlling heat flow has long been a dream for physicists and engineers, yet it’s remained elusive.”

But Hu and his colleagues may have found a solution. As reported last November in Science, his team has developed a new type of transistor that can precisely control heat flow by taking advantage of the basic chemistry of atomic bonding at the single-molecule level. These “thermal transistors” will likely be a central component of future circuits and will work in tandem with electrical transistors. The novel device is already affordable, scalable, and compatible with current industrial manufacturing practices, Hu says, and it could soon be incorporated into the production of lithium-ion batteries, combustion engines, semiconductor systems (such as computer chips), and more.

Scientists Finally Invent Heat-Controlling Circuitry That Keeps Electronics Cool, Rachel Newur, Scientific American

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All-Solid-State Batteries...

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 Comparison of cathode volume changes in all-solid-state cells under low-pressure operation. Credit: Korea Institute of Science and Technology

 

Topics: Batteries, Chemistry, Climate Change, Lithium, Materials Science, Nanomaterials

Often referred to as the "dream batteries," all-solid-state batteries are the next generation of batteries that many battery manufacturers are competing to bring to market. Unlike lithium-ion batteries, which use a liquid electrolyte, all components, including the electrolyte, anode, and cathode, are solid, reducing the risk of explosion, and are in high demand in markets ranging from automobiles to energy storage systems (ESS).

However, devices that maintain the high pressure (10s of MPa) required for stable operation of all-solid-state batteries have problems that reduce the battery performance, such as energy density and capacity, and must be solved for commercialization.

Dr. Hun-Gi Jung and his team at the Energy Storage Research Center at the Korea Institute of Science and Technology (KIST) have identified degradation factors that cause rapid capacity degradation and shortened lifespan when operating all-solid-state batteries at pressures similar to those of lithium-ion batteries. The research is published in the journal Advanced Energy Materials.

Unlike previous studies, the researchers confirmed for the first time that degradation can occur inside the cathode as well as outside, showing that all-solid-state batteries can be operated reliably even in low-pressure environments.

In all-solid-state batteries, the cathode and anode have a volume change during repeated charging and discharging, resulting in interfacial degradation, such as side reaction and contact loss between active materials and solid electrolytes, which increase the interfacial resistance and worsen cell performance.

To solve this problem, external devices are used to maintain high pressure, but this has the disadvantage of reducing energy density as the weight and volume of the battery increase. Research is being conducted on the inside of the all-solid-state cell to maintain the performance of the cell, even in low-pressure environments.

Investigation of the degradation mechanism for all-solid-state batteries takes another step toward commercialization, National Research Council of Science and Technology.

 

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Chemistry...

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Topics: Chemistry, Nanomaterials, Nanotechnology, Nobel Laureate, Nobel Prize

Prize announcement. NobelPrize.org. Nobel Prize Outreach AB 2023. Wed. 4 Oct 2023. < https://www.nobelprize.org/prizes/chemistry/2023/prize-announcement/ >

4 October 2023

The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Chemistry 2023 to

Moungi G. Bawendi
Massachusetts Institute of Technology (MIT), Cambridge, MA, USA

Louis E. Brus
Columbia University, New York, NY, USA

Alexei I. Ekimov
Nanocrystals Technology Inc., New York, NY, USA

“for the discovery and synthesis of quantum dots”

They planted an important seed for nanotechnology

The Nobel Prize in Chemistry 2023 rewards the discovery and development of quantum dots, nanoparticles so tiny that their size determines their properties. These smallest components of nanotechnology now spread their light from televisions and LED lamps and can also guide surgeons when they remove tumor tissue, among many other things.

Everyone who studies chemistry learns that an element’s properties are governed by how many electrons it has. However, when matter shrinks to nano-dimensions, quantum phenomena arise; these are governed by the size of the matter. The Nobel Laureates in Chemistry 2023 have succeeded in producing particles so small that their properties are determined by quantum phenomena. The particles, which are called quantum dots, are now of great importance in nanotechnology.

“Quantum dots have many fascinating and unusual properties. Importantly, they have different colors depending on their size,” says Johan Åqvist, Chair of the Nobel Committee for Chemistry.

Physicists had long known that, in theory, size-dependent quantum effects could arise in nanoparticles, but at that time, it was almost impossible to sculpt in nanodimensions. Therefore, few people believed that this knowledge would be put to practical use.

However, in the early 1980s, Alexei Ekimov succeeded in creating size-dependent quantum effects in colored glass. The color came from nanoparticles of copper chloride, and Ekimov demonstrated that the particle size affected the color of the glass via quantum effects.

A few years later, Louis Brus was the first scientist in the world to prove size-dependent quantum effects in particles floating freely in a fluid.

In 1993, Moungi Bawendi revolutionized the chemical production of quantum dots, resulting in almost perfect particles. This high quality was necessary for them to be utilized in applications.

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Polluting the Pristine...

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The sea floor near Australia’s Casey station in Antarctica has been found to have levels of pollution comparable to those in Rio de Janeiro’s harbor. Credit: Torsten Blackwood/AFP via Getty

Topics: Antarctica, Biology, Chemistry, Environment, Physics, Research

Antarctica is often described as one of the most pristine places in the world, but it has a dirty secret. Parts of the sea floor near Australia’s Casey research station are as polluted as the harbor in Rio de Janeiro, Brazil, according to a study published in PLoS ONE in August.

The contamination is likely to be widespread across Antarctica’s older research stations, says study co-author Jonathan Stark, a marine ecologist at the Australian Antarctic Division in Hobart. “These contaminants accumulate over long time frames and don’t just go away,” he says.

Stark and his colleagues found high concentrations of hydrocarbons — compounds found in fuels — and heavy metals, such as lead, copper, and zinc. Many of the samples were also loaded with polychlorinated biphenyls, highly carcinogenic chemical compounds that were common before their international ban in 2001.

When the researchers compared some of the samples with data from the World Harbor Project — an international collaboration that tracks large urban waterways — they found that lead, copper, and zinc levels in some cases were similar to those seen in parts of Sydney Harbour and Rio de Janeiro over the past two decades.

Widespread pollution

The problem of pollution is not unique to Casey station, says Ceisha Poirot, manager of policy, environment, and safety at Antarctica New Zealand in Christchurch. “All national programs are dealing with this issue,” she says. At New Zealand’s Scott Base — which is being redeveloped — contamination left from past fuel spills and poor waste management has been detected in soil and marine sediments. More of this historical pollution will emerge as the climate warms, says Poirot. “Things that were once frozen in the soil are now becoming more mobile,” she says.

Most of Antarctica’s contamination is due to historically poor waste management. In the old days, waste was often just dumped a small distance from research stations, says Terence Palmer, a marine scientist at Texas A&M University–Corpus Christi.

Research stations started to get serious about cleaning up their act in 1991. In that year, an international agreement known as the Protocol on Environmental Protection to the Antarctic Treaty, or the Madrid Protocol, was adopted. This designated Antarctica as a “natural reserve, devoted to peace and science,” and directed nations to monitor environmental impacts related to their activities. But much of the damage had already been done — roughly two-thirds of Antarctic research stations were built before 1991.

Antarctic research stations have polluted a pristine wilderness, Gemma Conroy, Nature.

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Quantum Slow Down...

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Topics: Chemistry, Computer Science, Quantum Computer, Quantum Mechanics

Scientists at the University of Sydney have, for the first time, used a quantum computer to engineer and directly observe a process critical in chemical reactions by slowing it down by a factor of 100 billion times.

Joint lead researcher and Ph.D. student Vanessa Olaya Agudelo said, "It is by understanding these basic processes inside and between molecules that we can open up a new world of possibilities in materials science, drug design, or solar energy harvesting.

"It could also help improve other processes that rely on molecules interacting with light, such as how smog is created or how the ozone layer is damaged."

Specifically, the research team witnessed the interference pattern of a single atom caused by a common geometric structure in chemistry called a "conical intersection."

Conical intersections are known throughout chemistry and are vital to rapid photochemical processes such as light harvesting in human vision or photosynthesis.

Chemists have tried to directly observe such geometric processes in chemical dynamics since the 1950s, but it is not feasible to observe them directly, given the extremely rapid timescales involved.

To get around this problem, quantum researchers in the School of Physics and the School of Chemistry created an experiment using a trapped-ion quantum computer in a completely new way. This allowed them to design and map this very complicated problem onto a relatively small quantum device—and then slow the process down by a factor of 100 billion. Their research findings are published August 28 in Nature Chemistry.

"In nature, the whole process is over within femtoseconds," said Olaya Agudelo from the School of Chemistry. "That's a billionth of a millionth—or one quadrillionth—of a second.

"Using our quantum computer, we built a system that allowed us to slow down the chemical dynamics from femtoseconds to milliseconds. This allowed us to make meaningful observations and measurements.

"This has never been done before."

Joint lead author Dr. Christophe Valahu from the School of Physics said, "Until now, we have been unable to directly observe the dynamics of 'geometric phase'; it happens too fast to probe experimentally.

"Using quantum technologies, we have addressed this problem."

Scientists use a quantum device to slow down simulated chemical reactions 100 billion times. University of Sydney, Phys.org.

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Beyond Heisenberg Compensators...

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The central role of HFIP: a solvent component that solvates POM. a. 1,1,1,3,3,3-Hexafluoro-2-propanol (HFIP): an effective solvent for polyoxymethylene (POM), the clustering of HFIP enabled the decrease of σ*OH energy38. b. Images of an undivided cell before (left) and after (right) the electrolysis. c. Reaction profile of POM bulk electrolysis at 3.5 V (60 °C), 0.1 M LiClO4 in CH3CN: HFIP (26:4). Credit: Nature Communications (2023). DOI: 10.1038/s41467-023-39362-z

Topics: Chemistry, Green Tech, Materials Science, Star Trek

A group of researchers at the University of Illinois Urbana-Champaign demonstrated a way to use the renewable energy source of electricity to recycle a form of plastic that's growing in use but more challenging to recycle than other popular forms of plastic.

In their study recently published in Nature Communications, they share their innovative process that shows the potential for harnessing renewable energy sources in the shift toward a circular plastics economy.

"We wanted to demonstrate this concept of bringing together renewable energy and a circular plastic economy," said Yuting Zhou, a postdoctoral associate, and co-author, who worked on this groundbreaking research with two professors in chemistry at Illinois, polymer expert Jeffrey Moore and electrochemistry expert Joaquín Rodríguez-López.

The project was conceived by Moore, who had experience working with Poly(phthalaldehyde), a form of polyacetal. Polyoxymethylene (POM) is a high-performance acetal resin that is used in a variety of industries, including automobiles and electronics. A thermoplastic, it can be shaped and molded when heated and hardens upon cooling with a high degree of strength and rigidity, making it an attractive lighter alternative to metal in some applications, like mechanical gears in automobiles. It is produced by various chemical firms with slightly different formulas and names, including Delrin by DuPont.

When recycling, those highly crystalline properties of POM make it difficult to break down. It can be melted and molded again, but POM's original material properties are lost, limiting the usefulness of the recycled material.

"When the polymer was in use as a product, it was not a pure polymer. It will also have other chemicals like coloring additives and antioxidants. So, if you simply melt it and remold it, the material properties are always lost," Zhou explained.

The Illinois research team's method uses electricity, which can be drawn from renewable sources, and takes place at room temperature.

This electro-mediated process deconstructs the polymer, breaking it down into monomers—the molecules that are bonded to other identical molecules to form polymers.

A recycling study demonstrates new possibilities for a circular plastics economy powered by renewable energy, Tracy Crane, University of Illinois at Urbana-Champaign.

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Cartoon Network...

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Mick Fleetwood's Maui Restaurant destroyed in Maui fire. Allison Rapp, Ultimate Classic Rock

Topics: Battery, Chemistry, Civics, Civilization, Climate Change, Democracy, Existentialism

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The Herculoids were a Hanna-Barbara cartoon that only ran for two seasons, from 1967 to 1969. From ages five to seven, I didn't demand much from my Saturday morning viewing pleasure: good guys, bad guys, action, good guys pummel bad guys, in this case, casting them off the planet. We landed on the Moon in their last year of air (it's a shame that history is now controversial). Dr. King and Robert Kennedy were assassinated In Medias Res. My understanding of Physics and STEM came much later.

Zandor, Tara, and Domo were the human protagonists defending planet "Amzot" (the writers threw spaghetti at the wall on this name). In a tepid reboot, they called it Quasar, a little more astrophysical but nonetheless kooky. They had a laser ray dragon (Zot), a rock ape (Igo), and a ten-legged rhino/triceratops hybrid that shot energy rocks from his snout (Tondro, the Terrific, because, yeah). Gloop and Gleep were human-sized, protoplasmic creatures called "the formless, fearless wonders," with eyes, and Gleep, was somehow the "son" of Gloop, without genitalia or gender (go with the bit?). The humans also shot energy rocks from slingshots at the foes too dumb to leave Zandor and his jungle planet alone. If the rocks were made of Lithium, they shouldn't have lasted too long: one of its properties is its volatility in oxygenated atmospheres.

In 1967, I would have been five years old and not too demanding of my visual entertainment on Saturday Morning Cartoons, as this old form pastime was called.

Taking a few courses in Physics drives a probing question and observation:

 

Where were the flocks of laser ray dragons, the congress of rock apes, the herds of rhino/triceratops hybrids, and what marshy bog did the "formless, fearless wonders" ascend from? It seemed Zot, Igo, Tondro, Gloop, and Gleep were the only ones of their kind.

In "Sarko: The Arkman," Sarko kidnaps Domo, Igo, and Tondro for his "collection" on another planet. Zandor rides Zot with Gloop to ANOTHER PLANET without the need of a spaceship, escape velocity, pressurized spacesuits, protection from radiation, or the friction of reentry to Sarko's world. Even if the planet was in the same orbital plane as Amzot, it didn't appear to take him long, and he wasn't bruised by a single meteor during the trip nor tanned from radiation burns (or dead). Gleep clones five copies of himself to protect Tara then turns up in a scene making himself a pillow on Sarko's world to catch Domo. Zot flew escort to Sarko's ship on the way back to Amzot again, with no loss of life. Did you follow all that?

Five-year-olds don't need Physics lessons, just a simple plot, a lot of action, and taking care of "evil-doers" before you play outside after Saturday cartoons.

It's magical thinking, but not a way to run human society.

 

"The human understanding is no dry light but receives an infusion from the will and affections; whence proceed sciences which may be called 'sciences as one would.' For what a man had rather were true, he more readily believes. Therefore, he rejects difficult things from impatience of research; sober things because they narrow hope; the deeper things of nature, from superstition; the light of experience, from arrogance and pride; things not commonly believed, out of the deference to the opinion of the vulgar. Numberless, in short, are the ways, and sometimes imperceptible, in which the affections color and infect the understanding."

Sir Francis Bacon, NOVUM ORGANON (1620)

 

Maui is a dystopian hellscape. It is now the deadliest wildfire in American history: until the next one. Reuters reports the cause of the fire is unknown, but 85% of all wildfires are caused by humans, as is the anthropogenic climate disruption that helped light the match. Hurricane Dora energized the spread, fanning the flames across the island that was experiencing a drought. Part of Maui's problem is prior to the predictions of climate scientists coming true in recent real-time, Maui never had to prepare for drought conditions or massive wildfires. Did I mention the island chain is surrounded by the Pacific Ocean?

Maui was the Capitol of the old kingdom of Hawaii before colonization. It was a tourist attraction and the seat of culture. Maui is the place where the Hula dance and the Samoan language were reconstituted and practiced. A 150-year-old banyan tree burned in the flames. It will survive IF the roots survived the savage flames.

 

"Some 271 structures were destroyed or damaged, the Honolulu Star-Advertiser said, citing official reports from the U.S. Civil Air Patrol and Maui Fire Department." Reuters

 

There is a throughline from Hurricane Katrina in Louisiana and Hurricane Dora in Maui. That throughline is climate change, gestated into the climate crisis, birthed into climate catastrophe. In eighteen years, we have shuffled, obfuscated, and kicked the can down the road right into our children's and grandchildren's future. We have allowed political operators and lobbyists for the fossil fuels industry to quote their "science as one would": "It's summer." "There is no climate change." "It's a (fill in the blank) hoax." "How can there be global warming if New York is blanketed in snow?"

The tobacco and fossil fuels industry used the same researchers and same lawyers to sway public opinion and sell their products. It is a myopic concentration on quarterly profits, not looking at the damage to the planet beneath them going forward. If Adam Smith's capitalism is our "salvation," there should be market-based solutions to ensure a functional civilization as corporations pursue profits and bought and paid-for politicians pursue policies that sustain both commerce and civilization.

Otherwise, their vulgar opinions have not offered solutions nor modeled societal collapse.

The Guardian reported from the National Academy of Science that more than 50% of life is in the soil beneath us. Life on Earth may survive our own hubris. It likely won't be intelligent or anything resembling human civilization.

Cartoon Network Physics is only good for five-year-olds on Saturday morning cartoons. There are no laser dragons, rock apes, rhino/triceratops-hybrids, and energy rocks to deploy to our rescue. It fails humanity in the long term. "Sciences as one would" has led us to this precipice. "Sciences as one acknowledges" will lead us away from it.

Note: The blog will resume Monday - Friday postings on August 21st (traveling for work).

 

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Tunnel Falls...

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Chip off the old block: Intel’s Tunnel Falls chip is based on silicon spin qubits, which are about a million times smaller than other qubit types. (Courtesy: Intel Corporation)

Topics: Applied Physics, Chemistry, Electrical Engineering, Quantum Computer, Quantum Mechanics

Intel – the world’s biggest computer-chip maker – has released its newest quantum chip and has begun shipping it to quantum scientists and engineers to use in their research. Dubbed Tunnel Falls, the chip contains a 12-qubit array and is based on silicon spin-qubit technology.

The distribution of the quantum chip to the quantum community is part of Intel’s plan to let researchers gain hands-on experience with the technology while at the same time enabling new quantum research.

The first quantum labs to get access to the chip include the University of Maryland, Sandia National Laboratories, the University of Rochester, and the University of Wisconsin-Madison.

The Tunnel Falls chip was fabricated on 300 mm silicon wafers in Intel’s “D1” transistor fabrication facility in Oregon, which can carry out extreme ultraviolet lithography (EUV) and gate and contact processing techniques.

Intel releases 12-qubit silicon quantum chip to the quantum community, Martijn Boerkamp, Physics World.

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Straining Moore...

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Topics: Applied Physics, Chemistry, Computer Science, Electrical Engineering, Materials Science, Nanotechnology, Quantum Mechanics, Semiconductor Technology

Gordon Moore, the co-founder of Intel who died earlier this year, is famous for forecasting a continuous rise in the density of transistors that we can pack onto semiconductor chips. James McKenzie looks at how “Moore’s law” is still going strong after almost six decades but warns that further progress is becoming harder and ever more expensive to sustain.

When the Taiwan Semiconductor Manufacturing Company (TSMC) announced last year that it was planning to build a new factory to produce integrated circuits, it wasn’t just the eye-watering $33bn price tag that caught my eye. What also struck me is that the plant, set to open in 2025 in the city of Hsinchu, will make the world’s first “2-nanometer” chips. Smaller, faster, and up to 30% more efficient than any microchip that has come before, TSMC’s chips will be sold to the likes of Apple – the company’s biggest customer – powering everything from smartphones to laptops.

But our ability to build such tiny, powerful chips shouldn’t surprise us. After all, the engineer Gordon Moore – who died on 24 March this year, aged 94 – famously predicted in 1965 that the number of transistors we can squeeze onto an integrated circuit ought to double yearly. Writing for the magazine Electronics (38 114), Moore reckoned that by 1975 it should be possible to fit a quarter of a million components onto a single silicon chip with an area of one square inch (6.25 cm2).

Moore’s prediction, which he later said was simply a “wild extrapolation”, held true, although, in 1975, he revised his forecast, predicting that chip densities would double every two years rather than every year. What thereafter became known as “Moore’s law” proved amazingly accurate, as the ability to pack ever more transistors into a tiny space underpinned the almost non-stop growth of the consumer electronics industry. In truth, it was never an established scientific “law” but more a description of how things had developed in the past as well as a roadmap that the semiconductor industry imposed on itself, driving future development.

Moore's law: further progress will push hard on the boundaries of physics and economics, James McKenzie, Physics World

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Magnetic Chirality...

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An RNA-making molecule crystallizes on magnetite, which can bias the process toward a single chiral form. S. FURKAN OZTURK

Topics: Biology, Biotechnology, Chemistry, Magnetism, Materials Science

In 1848, French chemist Louis Pasteur discovered that some molecules essential for life exist in mirror-image forms, much like our left and right hands. Today, we know biology chooses just one of these “chiral” forms: DNA, RNA, and their building blocks are all right-handed, whereas amino acids and proteins are all left-handed. Pasteur, who saw hints of this selectivity, or “homochirality,” thought magnetic fields might somehow explain it, but its origin has remained one of biology’s great mysteries. Now, it turns out Pasteur may have been onto something.

In three new papers, researchers suggest magnetic minerals common on early Earth could have caused key biomolecules to accumulate on their surface in just one mirror image form, setting off positive feedback that continued to favor the same form. “It’s a real breakthrough,” says Jack Szostak, an origin of life chemist at the University of Chicago who was not involved with the new work. “Homochirality is essential to get biology started, and this is [a possible]—and I would say very likely—solution.”

Chemical reactions are typically unbiased, yielding equal amounts of right- and left-handed molecules. But life requires selectivity: Only right-handed DNA, for example, has the correct twist to interact properly with other chiral molecules. To get [life], “you’ve got to break the mirror, or you can’t pull it off,” says Gerald Joyce, an origin of life chemist and president of the Salk Institute for Biological Studies.

Over the past century, researchers have proposed various mechanisms for skewing the first biomolecules, including cosmic rays and polarized light. Both can cause an initial bias favoring either right- or left-handed molecules, but they don’t directly explain how this initial bias was amplified to create the large reservoirs of chiral molecules likely needed to make the first cells. An explanation that creates an initial bias is a good start but “not sufficient,” says Dimitar Sasselov, a physicist at Harvard University and a leader of the new work.

‘Breakthrough’ could explain why life molecules are left- or right-handed, Robert F. Service, Science.org.

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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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