Tag Archives: nickel

The million-mile battery promised by Tesla is here

Elon Musk promised a battery that could take an e-vehicle a million miles and last for years at a time. Jeff Dahn, one of the pioneers of the modern lithium-ion batteries, has now delivered on that promise.

Image credits Paul Brennan.

In a new paper, Dahn announced that the company will soon be in possession of a battery that would make its robot taxis and long-haul electric trucks viable. Dahn is a Professor in the Department of Physics & Atmospheric Science and the Department of Chemistry at Dalhousie University, as well as a research partner of Tesla.

Charge for days

“Cells of this type should be able to power an electric vehicle for over one million miles and last at least two decades in grid energy storage” Dahn says.

Dahn’s research group is recognized as one of the most renowned and prestigious worldwide in the field of electrochemistry. Their new paper details the new power cell they created and a benchmark of its capabilities for further research.

The power cell is constructed using a nickel-rich NCM (nickel-cobalt-manganese) alloy for its cathode. The team explains that the alloy they used, known as NCM 523 (50% Nickel, 20% Cobalt, 30% Manganese), is stable and an excellent reference and starting point for further developments. Other elements that the team tested include graphite anodes, and different mixes of solvents, additives, and salt for the electrolyte solutions

All in all, the cells have a specific capacity (the ratio of energy storage ability to weight) 20% higher than that of the cathodes used in Li-ion batteries that power today’s mobile electronic devices. What’s more, the findings can be turned into useable batteries right away.

“However, since the goal of the study was to provide a reliable benchmark and reference for Li-ion battery technology, the specific energy density of the batteries described is not the highest compared to what can be really reached by advanced Li-ion batteries,” says Doron Aurbach the batteries and energy storage technical editor for the journal that published the study.

“Based on the study, Li-ion batteries will soon be developed that make driving over 500 kilometers (over 300 miles) from charge to charge possible.”

The paper “A Wide Range of Testing Results on an Excellent Lithium-Ion Cell Chemistry to be used as Benchmarks for New Battery Technologies” has been published in the Journal of The Electrochemical Society.

Metallic wood.

Researcher devise ‘metallic wood’ that’s stronger than titanium but could float on water

A team of US researchers has developed a light, but incredibly strong new material — they’re calling it metallic wood. This material, despite being a porous sheet of nickel, is as strong as titanium but four to five times lighter.

Metallic wood.

A microscopic sample of the researchers’ “metallic wood.”
Image credits University of Pennsylvania.

The way atoms stack in a lump of metal determines how strong that metal is — but we can’t (yet) produce such objects. For example, a sample of perfectly-stacked titanium would be ten times as strong as any titanium we can create today. This comes down to random defects that form in the manufacturing process, impacting the metal’s overall properties.  Materials researchers have been trying to exploit this phenomenon by taking an architectural approach, controlling the metal’s nanoscale layout to unlock the mechanical properties that arise at the nanoscale, where defects have reduced impact.

In a new study, researchers at the University of Pennsylvania’s School of Engineering and Applied Science, the University of Illinois at Urbana-Champaign, the Middle East Technical University in Turkey, and the University of Cambridge have designed a new material in which every atom is carefully laid out in its correct place, leading to a surprisingly high strength-to-weight ratio.

Woody metal

“The reason we call it metallic wood is not just its density, which is about that of wood, but its cellular nature,” says lead author James Pikul, Assistant Professor in the Department of Mechanical Engineering and Applied Mechanics at Penn Engineering.

“Cellular materials are porous; if you look at wood grain, that’s what you’re seeing — parts that are thick and dense and made to hold the structure, and parts that are porous and made to support biological functions, like transport to and from cells.”

The team writes that the material’s porous nature and the self-assembly process in which it’s created make it akin to wood and similar natural materials. Their metallic wood is made up of dense, strong metallic struts surrounding empty pores. The design operates “at the length scales where the strength of struts approaches the theoretical maximum,” Pikul explains.

Pikul’s team started with tiny plastic spheres of a few hundred nanometers in diameter, which they suspended in water. As the water slowly evaporated, the spheres stacked onto each other into an orderly, crystalline framework. The spheres were electroplated with nickel, then dissolved — leaving behind a network of metallic struts.

Material production process.

The fabrication process for a unit cell of the material. (b–g) Cross section SEM images of the (nickel inverse opal) material.

Each strut is around 10 nanometers wide, which is roughly the length of 100 nickel atoms, they explain. The team favored this production method over other techniques like 3D-printing as it’s easier to scale up.

“We’ve known that going smaller gets you stronger for some time,” Pikul says, “but people haven’t been able to make these structures with strong materials that are big enough that you’d be able to do something useful. Most examples made from strong materials have been about the size of a small flea, but with our approach, we can make metallic wood samples that are 400 times larger.”

“We’ve made foils of this metallic wood that are on the order of a square centimeter, or about the size of a playing die side,” he adds. “To give you a sense of scale, there are about 1 billion nickel struts in a piece that size.”

Because some 70% of the material is empty space, it has extremely low density in relation to its strength. It’s just a tad less dense than water, meaning a block of this material could float while still being stronger than most metal alloys today.

In a somewhat ironic twist, this process of creating metallic wood (which is metal in a wood-like configuration) is the opposite of how researchers at the University of Maryland created superdense wood (which is wood in a metal-like configuration).

The team is now focusing on expanding the production process to commercially relevant sizes. The materials used aren’t particularly rare or expensive on their own, but the infrastructure needed to carry out the production process is currently very limited. If that infrastructure is developed, however, the team is confident that their metallic wood can be produced more quickly and cheaply than their prototype sample.

A larger production base would also allow the team to further test their creation. Since they’ve only produced a tiny sample in the lab, the team is limited in what macroscale tests it can run on the material.

“We don’t know, for example, whether our metallic wood would dent like metal or shatter like glass.” Pikul says. “Just like the random defects in titanium limit its overall strength, we need to get a better understand of how the defects in the struts of metallic wood influence its overall properties.”

Another exciting possibility is merging the metallic wood with other materials to tailor it to a wide range of applications. Infusing it with anode and cathode materials, for example, would essentially turn the metallic wood into a very solid battery.

“The long-term interesting thing about this work is that we enable a material that has the same strength properties of other super high-strength materials but now it’s 70 percent empty space,” Pikul says.

“And you could one day fill that space with other things, like living organisms or materials that store energy.”

For example, the material could be used to produce smart prosthetics that store their own power — which would be pretty sweet.

The paper “High strength metallic wood from nanostructured nickel inverse opal materials” has been published in the journal Nature.

City smoke.

Prolonged exposure to Los Angeles Bay air induces dangerous mutations in the brains of rats

Mice trials suggest that city air may be even worse for your health than previously thought.

City smoke.

Image credits Johannes Plenio.

Prolonged exposure to fine particulate matter sourced air in the Los Angeles bay area does not do the brains of mice a lot of good. According to a new study published by researchers from the Cedars-Sinai Medical Center, a non-profit hospital in Los Angeles, it triggered inflammation and the appearance of cancer-associated genes in the animal’s neurons.

Brain trouble

The fact that air pollution is linked to a wide range of diseases isn’t exactly news by now — quite on the contrary. The adverse effects air pollution has on health have been widely documented and reported on. However, one new (and not exactly encouraging) discovery the team made is that certain materials in coarse air pollution — particularly nickel — may have a role promoting genetic changes that underpin the development of diseases such as cancer.

“This study, which looked at novel data gathered in the Los Angeles area, has significant implications for the assessment of air quality in the region, particularly as people are exposed to air pollution here for decades,” said lead author Julia Ljubimova, director of the Nanomedicine Research Center at Cedars-Sinai.

The team worked with one hundred mice — separated in groups of 6 to 10 animals. Each group was exposed to coarse (PM2.5–10: 2.5–10 µm in diameter), fine (PM<2.5: <2.5 µm), or ultrafine particles (UFPM: <0.15 µm) sourced from ambiental air in Riverside, California. Each type of particulate matter was analyzed using atomic emission spectroscopy, so the team had an idea of how much nickel, cobalt, and zinc they contained.

PM exposure lasted for 5 hours daily, 4 days per week for either two weeks (short exposure), one to three months (intermediate), or 12 months (long). One cohort of rats served as control and was kept in the same exposure chambers, for the same duration as the rats in the other groups, but was exposed to filtered air.

Afterward, the team analyzed the brains of each group to see how much of each metal had accumulated and whether this build-up had any effect on the organs’ health.

Metal build-up

They report that all three metals accumulated following intermediate-or-longer exposure. RNA sequencing revealed that intermediate exposure to PM2.5–10, which also correlated to nickel accumulation in the brain, triggered the expression of EGR2 — the early growth response gene 2 which regulates inflammatory processes — and of RAC1 — a gene that has the potential to cause cancer. The team believes the observed effects are a cumulative effect of exposure to the metals and certain toxins present in the air recovered from the Los Angeles Basin.

Furthermore, they report that coarse particulate matter from air pollution entered the body via two mechanisms. Trace metals and other pollutants could pass into the bloodstream from air inhaled through the lungs, later making their way to the brain. Alternatively, some of them could pass directly through mucosa in the nose, from where they had a much more direct pathway to the brain.

The study’s main limitations are that it only involved animal models — so the observed effects may carry over identically to humans — and that it only used a local ‘blend’ of pollutants — so the results may not be universally valid. Ljubimova notes that while the results may be unique to the Los Angeles Basin area, they do reinforce previous findings regarding the health consequences of exposure to air pollution in major cities.

Considering that most of humanity today lives with “unsafe” levels of air pollution, the findings are even more troubling.

“Our modern society is becoming increasingly urbanized and exposed to air pollution,” she says. “This trend underscores the need for additional research on the biology of air-pollution-induced organ damage, along with a concerted effort aimed at reducing ambient air pollution levels.”

The paper “Coarse particulate matter (PM2.5–10) in Los Angeles Basin air induces expression of inflammation and cancer biomarkers in rat brains” has been published in the journal Scientific Reports.

Hydrogen sign.

Solar fuels just years away, propelled by breakthrough in catalyst research

New research from Caltech could bring an economically-viable solar fuel to the market in the next few years.

Hydrogen sign.

Image credits Zero Emission Resource Organisation / Flickr.

One of the holy grails of renewable energy researchers which they have been pursuing for decades, is the brewing of economically-viable solar fuel. It sounds like something you drill out of the core of a star, but in reality, it’s both much more useful and less dramatic than that: “solar fuels” are chemical compounds which can be used to store solar energy.

Most of the recent research performed in this field focused on splitting water into its constituent parts (hydrogen and oxygen) using only sunlight. It’s easy to see why — hydrogen produced this way would be a clean, cheap, easy-to-produce and generally widely-available fuel. It could be used to power solar cells, motor vehicles, or even spin the turbines of power plants. One of it’s most attractive qualities is that it would be virtually endless and produces zero emissions: the only reactionary product of a hydrogen engine (which burns the gas, i.e. combines it back with oxygen) would be plain old water.

We’re actually pretty close to having the solar fuels we so desire, the only thing we’re missing is the “cheap” part. Back in 2014, a team of Caltech researchers led by Professor Harry developed a water-splitting catalyst from layers of nickel and iron. It worked pretty well for a prototype, showing that it has potential and could be scaled-up. However, while the catalyst clearly worked, nobody knew exactly how it did so. The working theory was that the nickel layers were somehow responsible for the material’s water-splitting ability.

Catalyst model chemical structure.

Ball-and-stick model of the catalyst’s molecular structure. Iron atoms are blue, nickel is green, oxygen is shown in red and hydrogen in white.
Image credits Caltech.

To get to the bottom of things, a team led by Bryan Hunter from Caltech’s Resnick Institute created an experiment during which the catalyst was starved of water, and observed how it behaved.

“When you take away some of the water, the reaction slows down, and you are able to take a picture of what’s happening during the reaction,” Bryan says.

The experiment revealed that the spot where water gets broken down on the catalyst — called its “active site” — wasn’t nickel, but iron atoms. The results are “very different” from what researchers expected to find, Hunter says. However, that isn’t a bad thing. Our initial hypothesis was a dud, but now that we know exactly how the alloy works — meaning we won’t waste time researching the wrong avenues.

“Now we can start making changes to this material to improve it.”

Gray believes the discovery will be a “game changer” in the field of solar fuels, alerting people that iron is “particularly good” for this type of applications. As we now know what we should look for, we can go on to the next step — which is finding out how to make such processes unfold faster and more efficient, which translates to lower costs of the final fuel.

“I wouldn’t be at all shocked if people start using these catalysts in commercial applications in four or five years.”

The paper “Trapping an Iron(VI) Water Splitting Intermediate in Nonaqueous Media” has been published in the journal Joule.

New species of metal-eating plant discovered in the Philippines

Scientists from the Philippines have discovered a new plant with an unusual lifestyle – it eats nickel for a living.

The new species is called Rinorea niccolifera, and it’s a part of the same genus as violets and pansies – but it has few things in common with those plants. Rinorea niccolifera‘s preferred food is nickel, accumulating up to 18,000 ppm of the metal in its leaves without itself being poisoned. 18,000 ppm is just a fancier way of saying 1.8% – which is quite an impressive figure!

Metal hyper accumulation in the plant kingdom is not unique in the plant kingdom, but it is extremely rare – in the case of nickel, it’s even more so. Throughout the world, only about 450 species are known for hyper accumulation of any kind – which, when you consider the total number of vascular plants (about 300,000 species), is not that much at all.

The new species, according to Dr Marilyn Quimado, one of the lead scientists of the research team, was discovered on the western part of Luzon Island in the Philippines. That area is particularly known for its abundance of heavy metals in the soils, which is why the plant evolved this way.

Potential applications

“Hyperacccumulator plants have great potentials for the development of green technologies, for example, ‘phytoremediation’ and ‘phytomining'”, explains Dr Augustine Doronila of the School of Chemistry, University of Melbourne, who is also co-author of the report.

It’s tempting to jump the gun and start thinking about using plants for metal exploitation (phytomining) – but that’s not really how it works. Plants have, of course, shallow roots, which would only allow for a surface exploitation, which is not really economically feasible. Even for gold sterile waste, scientists haven’t been able to make it work (though they’re getting pretty close) – and for a less valuable metal, like nickel, there’s virtually no chance.

But that doesn’t mean that this remarkable trait can’t be used in phytoremediation – using plants to clear out pollution. If you have a landmass that’s polluted with nickel, then Rinorea niccolifera might be a good bet. I’m sure we’ll be reading more studies about this plant pretty soon.

Ancient Egyptians had alien jewelry

This ancient Egyptian trinket may not look like much, but it hides a very interesting story. Researchers have found that the 5,000-year-old iron bead is actually made from a meteorite.

egyptian bead

The nickel rich areas (blue) suggest its meteoritic origin.

The nickel rich areas (blue) suggest its meteoritic origin.

 

Archaeologists have found iron objects in ancient Egypt, dating them to 2-3 millennia BC. But the earliest evidence of smelting only appeared much later after that, so how could they obtain these objects?

The result, published on 20 May in Meteoritics & Planetary Science, not only details this spectacular object, but also explains how ancient Egyptians obtained iron millennia before the earliest evidence of iron smelting in the region, solving the long standing archaeological mystery. It could also suggest (though that’s still debatable) that they regarded meteorites highly as they developed their religion.

“The sky was very important to the ancient Egyptians,” says Joyce Tyldesley, an Egyptologist at the University of Manchester, UK, and a co-author of the paper. “Something that falls from the sky is going to be considered as a gift from the gods.”

Using microscopy and computed tomography, Diane Johnson, a meteorite scientist at the Open University in Milton Keynes, UK, and her colleagues analyzed the object. Microscopy alone showed that it has a content in nickel of over 30%, which alone suggests that it came from a meteorite. acking up this result, the team observed that the metal had a distinctive crystalline structure called a Widmanstätten pattern. Widmanstätten patterns, also called Thomson structures, are unique figures of long nickel-iron crystals found only in meteorites.

Widmanstätten pattern example.

Widmanstätten pattern example.

But they took things one step further – using computed tomography (CT scan), they found that the object was created by hammering a fragment of iron from the meteorite into a thin plate, then bending it into a tube. They then re-created a 3D model of the object.

So what does this mean for the entire Egyptian culture? The object is dated 3,300 BC, and the first signs of smelting occur almost 3 millennia after, in 600 BC. It is known that back then, iron was associated with royalty and even dinivity. So where do meteorites stand? Some archaeologists believe Egyptians thought of them as fragments from the gods, descending from the sky as gifts. But was this technique common, or was it nothing more than an accident?

Johnson says that she would love to check other iron artefacts, but it remains to be seen if museums will actually allow her to do so – hopefully, they will.

Reference: Nature doi:10.1038/nature.2013.13091