Global Warming Is ‘Fundamentally’ Changing The Structure of Oceans

Climate change has wrought major changes to ocean stability faster than previously thought, according to a study published recently, raising alarms over its role as a global thermostat and the marine life it supports. The research published in the journal Nature looked at 50 years of data and followed the way in which surface waterdecouples” from the deeper oceanClimate change has disrupted ocean mixing, a process that helps store away most of the world’s excess heat and a significant proportion of CO2.

Water on the surface is warmer – and therefore less dense – than the water below, a contrast that is intensified by climate changeGlobal warming is also causing massive amounts of fresh water to flush into the seas from melting ice sheets and glaciers, lowering the salinity of the upper layer and further reducing its density. This increasing contrast between the density of the ocean layers makes mixing harder, so oxygen, heat and carbon are all less able to penetrate to the deep seas.

Similar to a layer of water on top of oil, the surface waters in contact with the atmosphere mix less efficiently with the underlying ocean,” said lead author Jean-Baptiste Sallee of Sorbonne University and France’s CNRS national scientific research center. He said while scientists were aware that this process was under way, “we here show that this change has occurred at a rate much quicker than previously thought: more than six times quicker.

Source: https://www.sciencealert.com/

How To Make EV Hydrogen Fuel Cells Last More

An international research team led by the University of Bern has succeeded in developing an electrocatalyst for hydrogen fuel cells which, in contrast to the catalysts commonly used today, does not require a carbon carrier and is therefore much more stable. The new process is industrially applicable and can be used to further optimize fuel cell powered vehicles without CO₂ emissionsFuel cells are gaining in importance as an alternative to battery-operated electromobility in heavy traffic, especially since hydrogen is a CO₂-neutral energy carrier if it is obtained from renewable sources.

For efficient operation, fuel cells need an electrocatalyst that improves the electrochemical reaction in which electricity is generated. The platinum-cobalt nanoparticle catalysts used as standard today have good catalytic properties and require only as little as necessary rare and expensive platinum. In order for the catalyst to be used in the fuel cell, it must have a surface with very small platinum-cobalt particles in the nanometer range, which is applied to a conductive carbon carrier material. Since the small particles and also the carbon in the fuel cell are exposed to corrosion, the cell loses efficiency and stability over time.

An international team led by Professor Matthias Arenz from the Department of Chemistry and Biochemistry (DCB) at the University of Bern has now succeeded in using a special process to produce an electrocatalyst without a carbon carrier, which, unlike existing catalysts, consists of a thin metal network and is therefore more durable.

The catalyst we have developed achieves high performance and promises stable fuel cell operation even at higher temperatures and high current density,” says Matthias Arenz.

The results have been published in Nature Materials.

Source: https://www.unibe.ch/

Thin Heat Shield For Superfast Aircraft

The world of aerospace increasingly relies on carbon fiber reinforced polymer composites to build the structures of satellites, rockets and jet aircraft. But the life of those materials is limited by how they handle heat.

A team of FAMU-FSU College of Engineering researchers from Florida State University’s High-Performance Materials Institute (HPMI) is developing a design for a heat shield that better protects those extremely fast machines. Their work will be published in the November edition of Carbon .

Right now, our flight systems are becoming more and more high-speed, even going into hypersonic systems, which are five times the speed of sound,” said Professor Richard Liang, director of HPMI. “When you have speeds that high, there’s more heat on a surface. Therefore, we need a much better thermal protection system.”

The team used carbon nanotubes, which are linked hexagons of carbon atoms in the shape of a cylinder, to build the heat shields. Sheets of those nanotubes are also known as “buckypaper,” a material with incredible abilities to conduct heat and electricity that has been a focus of study at HPMI. By soaking the buckypaper in a resin made of a compound called phenol, the researchers were able to create a lightweight, flexible material that is also durable enough to potentially protect the body of a rocket or jet from the intense heat it faces while flying.

Existing heat shields are often very thick compared to the base they protect, said Ayou Hao, a research faculty member at HPMI. This design lets engineers build a very thin shield, like a sort of skin that protects the aircraft and helps support its structure. After building heat shields of varying thicknesses, the researchers put them to the test.

One test involved applying a flame to the samples to see how they prevented heat from reaching the carbon fiber layer they were meant to protect. After that, the researchers bent the samples to see how strong they remained. They found the samples with sheets of buckypaper were better than control samples at dispersing heat and keeping it from reaching the base layer. They also stayed strong and flexible compared to control samples made without protective layers of nanotubes.

That flexibility is a helpful quality. The nanotubes are less vulnerable to cracking at high temperatures compared to ceramics, a typical heat shield material. They’re also lightweight, which is helpful for engineers who want to reduce the weight of anything on an aircraft that doesn’t help the way it flies.

Artificial Muscle

Wearing a flower brooch that blooms before your eyes sounds like magic. KAIST researchers have made it real with robotic muscles. Researchers have developed an ultrathin, artificial muscle for soft robotics. The advancement, recently reported in the journal Science Robotics, was demonstrated with a robotic blooming flower brooch, dancing robotic butterflies and fluttering tree leaves on a kinetic art piece.

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The robotic equivalent of a muscle that can move is called an actuator. The actuator expands, contracts or rotates like muscle fibers using a stimulus such as electricity. Engineers around the world are striving to develop more dynamic actuators that respond quickly, can bend without breaking, and are very durable. Soft, robotic muscles could have a wide variety of applications, from wearable electronics to advanced prosthetics.

The team from KAIST’s Creative Research Initiative Center for Functionally Antagonistic Nano-Engineering developed a very thin, responsive, flexible and durable artificial muscle. The actuator looks like a skinny strip of paper about an inch long. They used a particular type of material called MXene, which is class of compounds that have layers only a few atoms thick.

Their chosen MXene material (T3C2Tx) is made of thin layers of titanium and carbon compounds. It was not flexible by itself; sheets of material would flake off the actuator when bent in a loop. That changed when the MXene was “ionically cross-linked” — connected through an ionic bond — to a synthetic polymer. The combination of materials made the actuator flexible, while still maintaining strength and conductivity, which is critical for movements driven by electricity.

Their particular combination performed better than others reported. Their actuator responded very quickly to low voltage, and lasted for more than five hours moving continuously. To prove the tiny robotic muscle works actuator into wearable art: an origami-inspired brooch mimics how a narcissus, the team incorporated the flower unfolds its petals when a small amount of electricity is applied. They also designed robotic butterflies that move their wings up and down, and made the leaves of a tree sculpture flutter.

Wearable robotics and kinetic art demonstrate how robotic muscles can have fun and beautiful applications,” said Il-Kwon Oh, lead paper author and professor of mechanical engineering. “It also shows the enormous potential for small, artificial muscles for a variety of uses, such as haptic feedback systems and active biomedical devices.”

Source: https://www.kaist.ac.kr/

Electric Ice Cream Van

Nissan has partnered with the famous Mackies of Scotland to create a rather sweet concept vehicle. The electric vehicle pioneers and the ice cream brand have collaborated to create an all-electric ice cream van for “Clean Air Day” in the U.K. on June 20th, which demonstrates how a “Sky to Scoopapproach can remove carbon dependence at every stage of “the ice cream journey.”

Going green is nothing new for Mackies, which powers its family-owned dairy farm by renewable wind and solar energy, but most ice cream vans across Britain are powered by diesel engines which stay running even when the van is stopped to power the fridges and freezers onboard. In fact, some U.K. towns and cities are even looking to ban ice cream vans – which is a preposterous thought, even for someone like me who can’t eat ice cream. Nissan‘s new concept provides something of a solution to the impending doom of the good old ice cream van, reducing its carbon footprint while keeping kids happy and parents predictably out of pocket.

The ice cream van concept is based on Nissan‘s all-electric e-NV200 light commercial vehicle, which combines a zero-emission drivetrain, second-life battery storage and renewable solar energy generation for the home as well.

Ice cream is enjoyed the world over, but consumers are increasingly mindful of the environmental impact of how we produce such treats, and the ‘last mile’ of how they reach us,” said Kalyana Sivagnanam, managing director, Nissan Motor (GB) Ltd.

This project is a perfect demonstration of Nissan’s Intelligent Mobility strategy, applying more than a decade of EV experience and progress in battery technology to create cleaner solutions for power on the go – in ways customers might not expect. “By eliminating harmful tailpipe emissions, and increasing our use of renewable energy, we can help make this a better world for everyone.”

Source: https://www.motor1.com/

How To Create Electricity From Snowfall

Researchers from University of California at Los Angeles (UCLA) and colleagues have designed a new device that creates electricity from falling snow. The first of its kind, this device is inexpensive, small, thin and flexible like a sheet of plastic.

The device can work in remote areas because it provides its own power and does not need batteries,” said senior author Richard Kaner, who holds UCLA’s Dr. Myung Ki Hong Endowed Chair in Materials Innovation. “It’s a very clever device — a weather station that can tell you how much snow is falling, the direction the snow is falling, and the direction and speed of the wind.”

The researchers call it a snow-based triboelectric nanogenerator, or snow TENG. A triboelectric nanogenerator, which generates charge through static electricity, produces energy from the exchange of electrons.

Static electricity occurs from the interaction of one material that captures electrons and another that gives up electrons,” said Kaner, who is also a distinguished professor of chemistry and biochemistry, and of materials science and engineering, and a member of the California NanoSystems Institute at UCLA. “You separate the charges and create electricity out of essentially nothing.”

Snow is positively charged and gives up electrons. Silicone — a synthetic rubber-like material that is composed of silicon atoms and oxygen atoms, combined with carbon, hydrogen and other elements — is negatively charged. When falling snow contacts the surface of silicone, that produces a charge that the device captures, creating electricity.

Snow is already charged, so we thought, why not bring another material with the opposite charge and extract the charge to create electricity?” said co-author Maher El-Kady, a UCLA assistant researcher of chemistry and biochemistry.

While snow likes to give up electrons, the performance of the device depends on the efficiency of the other material at extracting these electrons,” he added. “After testing a large number of materials including aluminum foils and Teflon, we found that silicone produces more charge than any other material.”

Findings about the device are published in the journal Nano Energy.

Source: https://newsroom.ucla.edu/

Ruthenium-based Catalyst Outperforms Platinum To Produce Hydrogen

A novel ruthenium-based catalyst developed at UC Santa Cruz has shown markedly better performance than commercial platinum catalysts in alkaline water electrolysis for hydrogen production. The catalyst is a nanostructured composite material composed of carbon nanowires with ruthenium atoms bonded to nitrogen and carbon to form active sites within the carbon matrix.

The electrochemical splitting of water to produce hydrogen is a crucial step in the development of hydrogen as a clean, environmentally friendly fuel (for car or heating system). Much of the effort to reduce the cost and increase the efficiency of this process has focused on finding alternatives to expensive platinum-based catalysts. At UC Santa Cruz, researchers led by Shaowei Chen, professor of chemistry and biochemistry, have been investigating catalysts made by incorporating ruthenium and nitrogen into carbon-based nanocomposite materials. Their new findings, published February 7 in Nature Communications, not only demonstrate the impressive performance of their ruthenium-based catalyst but also provide insights into the mechanisms involved, which may lead to further improvements.

Electron microscopy of carbon nanowires co-doped with ruthenium and nitrogen shows ruthenium nanoparticles decorating the surface of the nanowires. Elemental mapping analysis shows individual ruthenium atoms within the carbon matrix (red arrows, below).

 

 

 

 

 

 

 

 

This is a clear demonstration that ruthenium can have remarkable activity in catalyzing the production of hydrogen from water,” Chen said. “We also characterized the material on the atomic scale, which helped us understand the mechanisms, and we can use these results for the rational design and engineering of ruthenium-based catalysts.

Electron microscopy and elemental mapping analysis of the material showed ruthenium nanoparticles as well as individual ruthenium atoms within the carbon matrix. Surprisingly, the researchers found that the main sites of catalytic activity were single ruthenium atoms rather than ruthenium nanoparticles.

Source: https://news.ucsc.edu/

Could Spruce Forests Offset Global Warming?

Researchers from the University of Lund in Sweden,  are measuring terpene particles emitted by spruce/fir forests, which are believed to have a cooling effect on the climate. They believe that planting more of this type of forest could help offset global warmingPlanting spruce forests could increase the carbon uptake. They would release aerosol particles which have a cooling effect on the earth.

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We saw that in the 1990s there was a big eruption of a volcano called Mount Pinatubo. It released an enormous amount of atmospheric particles into the air. Then the global climate was cooled for two years. And that’s how the atmospheric particles are acting on the climate. That’s one example of how the terpenes can cool the climate via atmospheric particles,” says Adam Kristensson, Nuclear physicist at the Lund University. Various of air samples  are being tested through solution reacting with carbon to find out if carbon comes from natural sources or fossil fuel burning.

Source: https://www.reuters.com/

How To Charge In Seconds 3D Batteries

The world is a big place, but it’s gotten smaller with the advent of technologies that put people from across the globe in the palm of one’s hand. And as the world has shrunk, it has also demanded that things happen ever faster – including the time it takes to charge an electronic device.

A cross-campus collaboration led by Ulrich Wiesner, Professor of Engineering in the Department of Materials Science at Cornell University, addresses this demand with a novel energy storage device architecture that has the potential for lightning-quick charges.

The group’s idea: Instead of having the batteries’ anode and cathode on either side of a nonconducting separator, intertwine the components in a self-assembling, 3D gyroidal structure, with thousands of nanoscale pores filled with the components necessary for energy storage and delivery.

A rendering of the 3D battery architecture (top; not to scale) with interpenetrating anode (grey, with minus sign), separator (green), and cathode (blue, plus sign), each about 20 nanometers in size. Below are their respective molecular structures

This is truly a revolutionary battery architecture,” said Wiesner, whose group’s paper, “Block Copolymer Derived 3-D Interpenetrating Multifunctional Gyroidal Nanohybrid for Electrical Energy Storage,” was published in Energy and Environmental Science, a publication of the Royal Society of Chemistry.

This three-dimensional architecture basically eliminates all losses from dead volume in your device,” Wiesner said. “More importantly, shrinking the dimensions of these interpenetrated domains down to the nanoscale, as we did, gives you orders of magnitude higher power density. In other words, you can access the energy in much shorter times than what’s usually done with conventional battery architectures.”

How fast is that? Wiesner said that, due to the dimensions of the battery’s elements being shrunk down to the nanoscale, “by the time you put your cable into the socket, in seconds, perhaps even faster, the battery would be charged.”

The architecture for this concept is based on block copolymer self-assembly, which the Wiesner group has employed for years in other devices, including a gyroidal solar cell and a gyroidal superconductor. Joerg Werner, Ph.D. ’15, lead author on this work, had experimented with self-assembling filtration membranes, and wondered if the same principles could be applied to carbon materials for energy storage.

Source: http://news.cornell.edu/

Perovskite Solar Cells One Giant Step Closer To The Market

Harnessing energy from the sun, which emits immensely powerful energy from the center of the solar system, is one of the key targets for achieving a sustainable energy supplyLight energy can be converted directly into electricity using electrical devices called solar cells. To date, most solar cells are made of silicon, a material that is very good at absorbing light. But silicon panels are expensive to produce.

Scientists have been working on an alternative, made from perovskite structures. True perovskite, a mineral found in the earth, is composed of calcium, titanium and oxygen in a specific molecular arrangement. Materials with that same crystal structure are called perovskite structuresPerovskite structures work well as the light-harvesting active layer of a solar cell because they absorb light efficiently but are much cheaper than silicon. They can also be integrated into devices using relatively simple equipment. For instance, they can be dissolved in solvent and spray coated directly onto the substrate.

Materials made from perovskite structures could potentially revolutionize solar cell devices, but they have a severe drawback: they are often very unstable, deteriorating on exposure to heat. This has hindered their commercial potential. The Energy Materials and Surface Sciences Unit at the Okinawa Institute of Science and Technology Graduate University (OIST), led by Prof. Yabing Qi, has developed devices using a new perovskite material that is stable, efficient and relatively cheap to produce, paving the way for their use in the solar cells of tomorrow. This material has several key features:

  • First, it is completely inorganic – an important shift, because organic components are usually not thermostable and degrade under heat. Since solar cells can get very hot in the sun, heat stability is crucial. By replacing the organic parts with inorganic materials, the researchers made the perovskite solar cells much more stable..  “The solar cells are almost unchanged after exposure to light for 300 hours,” says Dr. Zonghao Liu, an author on the paper.
  • Second feature: Inorganic perovskite solar cells tend to have lower light absorption than organic-inorganic hybrids, however, but the OIST researchers doped their new cells with manganese in order to improve their performance. Manganese changes the crystal structure of the material, boosting its light harvesting capacity.  “Just like when you add salt to a dish to change its flavor, when we add manganese, it changes the properties of the solar cell,” says Liu.
  • Thirdly, in these solar cells, the electrodes that transport current between the solar cells and external wires are made of carbon, rather than of the usual gold. Such electrodes are significantly cheaper and easier to produce, in part because they can be printed directly onto the solar cells. Fabricating gold electrodes, on the other hand, requires high temperatures and specialist equipment such as a vacuum chamber.

The findings are published in Advanced Energy Materials. Postdoctoral scholars Dr. Jia Liang and Dr. Zonghao Liu made major contributions to this work.

Source: https://www.oist.jp/