Category Archives: energy

Tamarind shells turned into carbon nanosheets for supercapacitors

Fro anyone who needs a shot of happiness, this is a very happy scientist,

Caption: Assistant Professor (Steve) Cuong Dang, from NTU’s School of Electrical and Electronic Engineering, who led the study, displaying pieces of tamarind shell, which were integral to the study. Credit to NTU Singapore

A July 14, 2021 news item on ScienceDaily describes the source of assistant professor (Steve) Cuong Dang’s happiness,

Shells of tamarind, a tropical fruit consumed worldwide, are discarded during food production. As they are bulky, tamarind shells take up a considerable amount of space in landfills where they are disposed as agricultural waste.

However, a team of international scientists led by Nanyang Technological University, Singapore (NTU Singapore) has found a way to deal with the problem. By processing the tamarind shells which are rich in carbon, the scientists converted the waste material into carbon nanosheets, which are a key component of supercapacitors – energy storage devices that are used in automobiles, buses, electric vehicles, trains, and elevators.

The study reflects NTU’s commitment to address humanity’s grand challenges on sustainability as part of its 2025 strategic plan, which seeks to accelerate the translation of research discoveries into innovations that mitigate our impact on the environment.

A July 14, 2021 NTU press release (also here [scroll down to click on the link to the full press release] and on EurekAlert but published July 13, 2021), which originated the news item, delves further into the topic,

he team, made up of researchers from NTU Singapore, the Western Norway University of Applied Sciences in Norway, and Alagappa University in India, believes that these nanosheets, when scaled up, could be an eco-friendly alternative to their industrially produced counterparts, and cut down on waste at the same time.

Assistant Professor (Steve) Cuong Dang, from NTU’s School of Electrical and Electronic Engineering, who led the study, said: “Through a series of analysis, we found that the performance of our tamarind shell-derived nanosheets was comparable to their industrially made counterparts in terms of porous structure and electrochemical properties. The process to make the nanosheets is also the standard method to produce active carbon nanosheets.”

Professor G. Ravi, Head, Department of Physics, who co-authored the study with Asst Prof Dr R. Yuvakkumar, who are both from Alagappa University, said: “The use of tamarind shells may reduce the amount of space required for landfills, especially in regions in Asia such as India, one of the world’s largest producers of tamarind, which is also grappling with waste disposal issues.”

The study was published in the peer-reviewed scientific journal Chemosphere in June [2021].

The step-by-step recipe for carbon nanosheets

To manufacture the carbon nanosheets, the researchers first washed tamarind fruit shells and dried them at 100°C for around six hours, before grinding them into powder.

The scientists then baked the powder in a furnace for 150 minutes at 700-900 degrees Celsius in the absence of oxygen to convert them into ultrathin sheets of carbon known as nanosheets.

Tamarind shells are rich in carbon and porous in nature, making them an ideal material from which to manufacture carbon nanosheets.

A common material used to produce carbon nanosheets are industrial hemp fibres. However, they require to be heated at over 180°C for 24 hours – four times longer than that of tamarind shells, and at a higher temperature. This is before the hemp is further subjected to intense heat to convert them into carbon nanosheets.

Professor Dhayalan Velauthapillai, Head of the research group for Advanced Nanomaterials for Clean Energy and Health Applications at Western Norway University of Applied Sciences, who participated in the study, said: “Carbon nanosheets comprise of layers of carbon atoms arranged in interconnecting hexagons, like a honeycomb. The secret behind their energy storing capabilities lies in their porous structure leading to large surface area which help the material to store large amounts of electric charges.”

The tamarind shell-derived nanosheets also showed good thermal stability and electric conductivity, making them promising options for energy storage.

The researchers hope to explore larger scale production of the carbon nanosheets with agricultural partners. They are also working on reducing the energy needed for the production process, making it more environmentally friendly, and are seeking to improve the electrochemical properties of the nanosheets.

The team also hopes to explore the possibility of using different types of fruit skins or shells to produce carbon nanosheets.

Here’s a link to and a citation for the paper,

Cleaner production of tamarind fruit shell into bio-mass derived porous 3D-activated carbon nanosheets by CVD technique for supercapacitor applications by V. Thirumal, K. Dhamodharan, R. Yuvakkumar, G. Ravi, B. Saravanakumar, M. Thambidurai, Cuong Dang, Dhayalan Velauthapillai. Chemosphere Volume 282, November 2021, 131033 DOI: https://doi.org/10.1016/j.chemosphere.2021.131033 Available online 2 June 2021.

This paper is behind a paywall.

Because we could all do with a little more happiness these days,

Caption: (L-R) Senior Research Fellow Dr Thambidurai Mariyappan, also from NTU’s School of Electrical and Electronic Engineering, who was part of the study, and Asst Prof Dang, holding up tamarind pods. Credit to NTU Singapore

General Fusion moves headquarters to Vancouver Airport (sort of)

Nuclear energy is not usually of much interest to me but there is a Canadian company doing some interesting work in that area. So, before getting to the news about the company’s move, here’s a general description of fusion energy and how General Fusion (the company) is approaching the clean energy problem, from a June 18, 2021 posting by Bob McDonald on the Canadian Broadcasting Corporation’s (CBC) Quirks and Quarks blog (Note: Links have been removed),

Vancouver-based fusion energy company General Fusion has entered an agreement with the United Kingdom Atomic Energy Authority to build a nuclear fusion demonstration plant to be operational in 2025. It will take a unique approach to generating clean energy.   

There is an industry joke that fusion energy has been 20 years away for 50 years. The quest to produce clean energy by duplicating the processes happening at the centre of the sun has been a difficult and expensive challenge.

It has yet to be accomplished on anything like a commercial scale. That is partly because on Earth the fusion process involves handling materials at extreme pressures and temperatures many times hotter than the surface of the sun.

The nuclear technology that has provided electricity for decades around the world relies on fission, which splits heavy atoms such as uranium into lighter elements, releasing energy. However, this produces hazardous and durable radioactive waste that must be stored, and more catastrophically has led to major accidents at Chernobyl and Fukushima.

Fusion is the opposite of fission. Lighter elements such as hydrogen are heated and compressed to fuse into heavier ones. This releases energy, but with a much smaller legacy of radioactive waste, and no risk of meltdown.

The world’s largest fusion reactor experiment, ITER (Latin for “the way”) [International Thermonuclear Experimental Reactor] is currently under construction in southern France. It’s a massive international collaboration developing on fusion technology that’s been been explored since it was invented in the Soviet Union in the 1950s. It involves a doughnut-shaped metallic chamber called a tokamak that is surrounded by incredibly powerful superconducting magnets. 

An electrically charged gas, or plasma, will be injected into the chamber where the magnets hold it, compressed and suspended, so it does not touch the walls and burn through them. The plasma will be heated to the unbelievable temperature of 150 million C, when fusion begins to take place.

And therein lies the problem. So far, experimental fusion reactors have required more energy to heat the plasma to start the fusion reaction than can be harvested from the reaction itself. Size is part of the problem. Demonstration reactors are small and meant to test equipment and materials, not produce power. ITER is supposed to be large enough to produce 10 times as much power as is required to heat up its plasma.

And that’s the holy grail of fusion: to produce enough power that the nuclear fusion reaction can become self-sustaining.

General Fusion takes a completely different approach by using mechanical pressure to contain and heat the plasma, rather than gigantic electromagnets. A series of powerful pistons surround a container of liquid metal with the hydrogen plasma in the centre. The pistons mechanically squeeze the liquid on all sides at once, heating the fuel by compression the way fuel in a diesel engine is compressed and heated in a cylinder until it ignites. 

Exciting, eh? If you have time, you may want to read McDonald’s June 18, 2021 posting for a few more details about General Fusion’s technology and for some embedded images.

At one point I was under the impression that General Fusion was involved with ITER but that seems to have been a misunderstanding on my part.

I first wrote about General Fusion in a December 2, 2011 posting titled: Burnaby-based company (Canada) challenges fossil fuel consumption with nuclear fusion. (For those unfamiliar with the Vancouver area, there’s the city of Vancouver and there’s Vancouver Metro, which includes the city of Vancouver and others in the region. Burnaby is part of Metro Vancouver; General Fusion is moving to Sea Island (near Vancouver Airport), in Richmond, which is also in Metro Vancouver.) Kenneth Chan’s October 20, 2021 article for the Daily Hive gives more detail about General Fusion’s new facilities (Note: A link has been removed),

The new facility will span two buildings at 6020 and 6082 Russ Baker Way, near YVR’s [Vancouver Airport] South Terminal. This includes a larger building previously used for aircraft engine maintenance and repair.

The relocation process could start before the end of 2021, allowing the company to more than quadruple its workforce over the coming years. Currently, it employs about 140 people.

The Sea Island [in Richmond] facility will house its corporate offices, primary fusion technology development division, and many of its engineering laboratories. This new facility provides General Fusion with the ability to build a new demonstration prototype to support the commercialization of its magnetized target fusion technology.

The company’s research and development into practical fusion technology as a zero-carbon power solution to address the world’s growing energy needs, while fighting climate change, is supported by the federal governments of Canada, US, and UK.

General Fusion is backed by dozens of large global private investors, including Bezos Expeditions, which is the personal investment entity for Amazon founder Jeff Bezos. It has raised a total of about USD$200 million in financing to date.

“British Columbia is at the centre of a thriving, world-class technology innovation ecosystem, just the right place for us to continue investing in our growing workforce and the future of our company,” said Christofer Mowry, CEO of General Fusion, in a statement.

Earlier this year, YVR also indicated it is considering allowing commercial and industrial developments on several hundred acres of under-utilized parcels of land next to the north and south runways, for uses that complement airport activities. This would also provide the airport with a new source of revenue, after major financial losses from the years-long impact of COVID-19.

You can find General Fusion here and you can find ITER here.

The coolest paint

It’s the ‘est’ of it all. The coolest, the whitest, the blackest … Scientists and artists are both pursuing the ‘est’. (More about the pursuit later in this posting.)

In this case, scientists have developed the coolest, whitest paint yet. From an April 16, 2021 news item on Nanowerk,

In an effort to curb global warming, Purdue University engineers have created the whitest paint yet. Coating buildings with this paint may one day cool them off enough to reduce the need for air conditioning, the researchers say.

In October [2020], the team created an ultra-white paint that pushed limits on how white paint can be. Now they’ve outdone that. The newer paint not only is whiter but also can keep surfaces cooler than the formulation that the researchers had previously demonstrated.

“If you were to use this paint to cover a roof area of about 1,000 square feet, we estimate that you could get a cooling power of 10 kilowatts. That’s more powerful than the central air conditioners used by most houses,” said Xiulin Ruan, a Purdue professor of mechanical engineering.

Caption: Xiulin Ruan, a Purdue University professor of mechanical engineering, holds up his lab’s sample of the whitest paint on record. Credit: Purdue University/Jared Pike

This is nicely done. Researcher Xiulin Ruan is standing close to a structure that could be said to resemble the sun while in shirtsleeves and sunglasses and holding up a sample of his whitest paint in April (not usually a warm month in Indiana).

An April 15, 2021 Purdue University news release (also on EurkeAlert), which originated the news item, provides more detail about the work and hints about its commercial applications both civilian and military,

The researchers believe that this white may be the closest equivalent of the blackest black, “Vantablack,” [emphasis mine; see comments later in this post] which absorbs up to 99.9% of visible light. The new whitest paint formulation reflects up to 98.1% of sunlight – compared with the 95.5% of sunlight reflected by the researchers’ previous ultra-white paint – and sends infrared heat away from a surface at the same time.

Typical commercial white paint gets warmer rather than cooler. Paints on the market that are designed to reject heat reflect only 80%-90% of sunlight and can’t make surfaces cooler than their surroundings.

The team’s research paper showing how the paint works publishes Thursday (April 15 [2021]) as the cover of the journal ACS Applied Materials & Interfaces.

What makes the whitest paint so white

Two features give the paint its extreme whiteness. One is the paint’s very high concentration of a chemical compound called barium sulfate [emphasis mine] which is also used to make photo paper and cosmetics white.

“We looked at various commercial products, basically anything that’s white,” said Xiangyu Li, a postdoctoral researcher at the Massachusetts Institute of Technology who worked on this project as a Purdue Ph.D. student in Ruan’s lab. “We found that using barium sulfate, you can theoretically make things really, really reflective, which means that they’re really, really white.”

The second feature is that the barium sulfate particles are all different sizes in the paint. How much each particle scatters light depends on its size, so a wider range of particle sizes allows the paint to scatter more of the light spectrum from the sun.

“A high concentration of particles that are also different sizes gives the paint the broadest spectral scattering, which contributes to the highest reflectance,” said Joseph Peoples, a Purdue Ph.D. student in mechanical engineering.

There is a little bit of room to make the paint whiter, but not much without compromising the paint.”Although a higher particle concentration is better for making something white, you can’t increase the concentration too much. The higher the concentration, the easier it is for the paint to break or peel off,” Li said.

How the whitest paint is also the coolest

The paint’s whiteness also means that the paint is the coolest on record. Using high-accuracy temperature reading equipment called thermocouples, the researchers demonstrated outdoors that the paint can keep surfaces 19 degrees Fahrenheit cooler than their ambient surroundings at night. It can also cool surfaces 8 degrees Fahrenheit below their surroundings under strong sunlight during noon hours.

The paint’s solar reflectance is so effective, it even worked in the middle of winter. During an outdoor test with an ambient temperature of 43 degrees Fahrenheit, the paint still managed to lower the sample temperature by 18 degrees Fahrenheit.

This white paint is the result of six years of research building on attempts going back to the 1970s to develop radiative cooling paint as a feasible alternative to traditional air conditioners.

Ruan’s lab had considered over 100 different materials, narrowed them down to 10 and tested about 50 different formulations for each material. Their previous whitest paint was a formulation made of calcium carbonate, an earth-abundant compound commonly found in rocks and seashells.

The researchers showed in their study that like commercial paint, their barium sulfate-based paint can potentially handle outdoor conditions. The technique that the researchers used to create the paint also is compatible with the commercial paint fabrication process.

Patent applications for this paint formulation have been filed through the Purdue Research Foundation Office of Technology Commercialization. This research was supported by the Cooling Technologies Research Center at Purdue University and the Air Force Office of Scientific Research [emphasis mine] through the Defense University Research Instrumentation Program (Grant No.427 FA9550-17-1-0368). The research was performed at Purdue’s FLEX Lab and Ray W. Herrick Laboratories and the Birck Nanotechnology Center of Purdue’s Discovery Park.

Here’s a link to and a citation for the paper,

Ultrawhite BaSO4 Paints and Films for Remarkable Daytime Subambient Radiative Cooling by Xiangyu Li, Joseph Peoples, Peiyan Yao, and Xiulin Ruan. ACS Appl. Mater. Interfaces 2021, XXXX, XXX, XXX-XXX DOI: https://doi.org/10.1021/acsami.1c02368 Publication Date:April 15, 2021 © 2021 American Chemical Society

This paper is behind a paywall.

Vantablack and the ongoing ‘est’ of blackest

Vantablack’s 99.9% light absorption no longer qualifies it for the ‘blackest black’. A newer standard for the ‘blackest black’ was set by the US National Institute of Standards and Technology at 99.99% light absorption with its N.I.S.T. ultra-black in 2019, although that too seems to have been bested.

I have three postings covering the Vantablack and blackest black story,

The third posting (December 2019) provides a brief summary of the story along with what was the latest from the US National Institute of Standards and Technology. There’s also a little bit about the ‘The Redemption of Vanity’ an art piece demonstrating the blackest black material from the Massachusetts Institute of Technology, which they state has 99.995% (at least) absorption of light.

From a science perspective, the blackest black would be useful for space exploration.

I am surprised there doesn’t seem to have been an artistic rush to work with the whitest white. That impression may be due to the fact that the feuds get more attention than quiet work.

Dark side to the whitest white?

Andrew Parnell, research fellow in physics and astronomy at the University of Sheffield (UK), mentions a downside to obtaining the material needed to produce this cooling white paint in a June 10, 2021 essay on The Conversation (h/t Fast Company), Note: Links have been removed,

… this whiter-than-white paint has a darker side. The energy required to dig up raw barite ore to produce and process the barium sulphite that makes up nearly 60% of the paint means it has a huge carbon footprint. And using the paint widely would mean a dramatic increase in the mining of barium.

Parnell ends his essay with this (Note: Links have been removed),

Barium sulphite-based paint is just one way to improve the reflectivity of buildings. I’ve spent the last few years researching the colour white in the natural world, from white surfaces to white animals. Animal hairs, feathers and butterfly wings provide different examples of how nature regulates temperature within a structure. Mimicking these natural techniques could help to keep our cities cooler with less cost to the environment.

The wings of one intensely white beetle species called Lepidiota stigma appear a strikingly bright white thanks to nanostructures in their scales, which are very good at scattering incoming light. This natural light-scattering property can be used to design even better paints: for example, by using recycled plastic to create white paint containing similar nanostructures with a far lower carbon footprint. When it comes to taking inspiration from nature, the sky’s the limit.

Technology for mopping up oil spills

It’s a little disheartening to write about technology for mopping up oils spills as there doesn’t to be much improvement in the situation as Adele Peters notes in her June 4, 2021 article (A decade after Deepwater Horizon, we’re still cleaning up oil spills the same way) for Fast Company (Note: Links have been removed),

Off the coastline of Sri Lanka, where a burning cargo ship has been spilling toxic chemicals and plastic pellets over the past two weeks, the government is preparing for the next possible stage of the disaster: As the ship sinks, it may also spill some of the hundreds of tons of oil in its fuel tanks.

The government is readying oil dispersants, booms, and oil skimmers, all tools that were used in the massive Deepwater Horizon oil spill in the Gulf of Mexico in 2010. They didn’t work perfectly then—more than 1,000 miles of shoreline were polluted—and more than a decade later, they’re still commonly used. But solutions that might work better are under development, including reusable sponges that can suck up oil both on the surface and underwater.

Dispersants, one common tool now, are chemicals designed to break up the oil into tiny droplets so that, in theory, microorganisms in the water can break down the oil more easily. But at least one study found that dispersant could harm those organisms. Deep-sea coral also appears to suffer more from the mix of dispersant and oil than oil alone. Booms are designed to contain oil on the surface so it can be scraped off with a skimmer, but that only works if the water’s relatively calm, and it doesn’t deal with oil below the surface. The oil on the surface can also be burned, but it creates a plume of thick black smoke. “That does get rid of the oil from the water, but then it turns a water pollution problem into an air pollution problem,” says Seth Darling, a senior scientist at Argonne National Laboratory who developed an alternative called the Oleo Sponge [emphasis mine].

… a team from two German universities that developed a system of wood chips that can be dropped in the water to collect oil even in rough weather, when current tools don’t work well. The system is ready for deployment if a spill happens in the Baltic Sea. Another earlier-stage solution proposes using a robot to detect and capture oil.

I’m glad to see at least one new oil spill cleanup technology being readied for deployment in Peters’ June 4, 2021 article, we should be preparing for more spills as the Arctic melts and plans are made to develop new shipping routes.

Amongst other oil spill cleanup technologies, Peters mentions the ‘Oleo Sponge’, which was featured here in a March 30, 2017 posting when researchers were looking for investors to commercialize the product. According to Peters the oleo sponge hasn’t yet made it to market; it’s a fate many of these technologies are destined to meet. Meanwhile, scientists continue to develop new methods and techniques for mopping up oil spills as safely as possible. For example, there’s an oil spill sucking robot mentioned in my October 30, 2020 posting, which features yet another article by Peters.

In the summer of 2020 there were two major oil spills, one in the Russian Arctic and one in an ecologically sensitive area near Mauritius. For more about those events, there’s an August 14, 2020 posting, which starts with news of an oil spill technology featuring dog fur and then focuses primarily on the oil spill in the Russian Arctic with a brief mention of the spill near Mauritius in June 2020 (scroll down to the ‘Exceptionally warm weather’ subhead and see the paragraph above it for the mention and a link to a story).

Carbon nanotubes can scavenge energy from environment to generate electricity

A June 7, 2021 news item on phys.org announces research into a new method for generating electricity (Note: A link has been removed),

MIT [Massachusetts Institute of Technology] engineers have discovered a new way of generating electricity using tiny carbon particles that can create a current simply by interacting with liquid surrounding them.

The liquid, an organic solvent, draws electrons out of the particles, generating a current that could be used to drive chemical reactions or to power micro- or nanoscale robots, the researchers say.

“This mechanism is new, and this way of generating energy is completely new,” says Michael Strano, the Carbon P. Dubbs Professor of Chemical Engineering at MIT. “This technology is intriguing because all you have to do is flow a solvent through a bed of these particles. This allows you to do electrochemistry, but with no wires.”

A June 7, 2021 MIT news release (also on EurekAlert), which generated the news item, delves further into the research,

In a new study describing this phenomenon, the researchers showed that they could use this electric current to drive a reaction known as alcohol oxidation — an organic chemical reaction that is important in the chemical industry.

Strano is the senior author of the paper, which appears today [June 7, 2021] in Nature Communications. The lead authors of the study are MIT graduate student Albert Tianxiang Liu and former MIT researcher Yuichiro Kunai. Other authors include former graduate student Anton Cottrill, postdocs Amir Kaplan and Hyunah Kim, graduate student Ge Zhang, and recent MIT graduates Rafid Mollah and Yannick Eatmon.

Unique properties

The new discovery grew out of Strano’s research on carbon nanotubes — hollow tubes made of a lattice of carbon atoms, which have unique electrical properties. In 2010, Strano demonstrated, for the first time, that carbon nanotubes can generate “thermopower waves.” When a carbon nanotube is coated with layer of fuel, moving pulses of heat, or thermopower waves, travel along the tube, creating an electrical current.

That work led Strano and his students to uncover a related feature of carbon nanotubes. They found that when part of a nanotube is coated with a Teflon-like polymer, it creates an asymmetry that makes it possible for electrons to flow from the coated to the uncoated part of the tube, generating an electrical current. Those electrons can be drawn out by submerging the particles in a solvent that is hungry for electrons.

To harness this special capability, the researchers created electricity-generating particles by grinding up carbon nanotubes and forming them into a sheet of paper-like material. One side of each sheet was coated with a Teflon-like polymer, and the researchers then cut out small particles, which can be any shape or size. For this study, they made particles that were 250 microns by 250 microns.

When these particles are submerged in an organic solvent such as acetonitrile, the solvent adheres to the uncoated surface of the particles and begins pulling electrons out of them.

“The solvent takes electrons away, and the system tries to equilibrate by moving electrons,” Strano says. “There’s no sophisticated battery chemistry inside. It’s just a particle and you put it into solvent and it starts generating an electric field.”

Particle power

The current version of the particles can generate about 0.7 volts of electricity per particle. In this study, the researchers also showed that they can form arrays of hundreds of particles in a small test tube. This “packed bed” reactor generates enough energy to power a chemical reaction called an alcohol oxidation, in which an alcohol is converted to an aldehyde or a ketone. Usually, this reaction is not performed using electrochemistry because it would require too much external current.

“Because the packed bed reactor is compact, it has more flexibility in terms of applications than a large electrochemical reactor,” Zhang says. “The particles can be made very small, and they don’t require any external wires in order to drive the electrochemical reaction.”

In future work, Strano hopes to use this kind of energy generation to build polymers using only carbon dioxide as a starting material. In a related project, he has already created polymers that can regenerate themselves using carbon dioxide as a building material, in a process powered by solar energy. This work is inspired by carbon fixation, the set of chemical reactions that plants use to build sugars from carbon dioxide, using energy from the sun.

In the longer term, this approach could also be used to power micro- or nanoscale robots. Strano’s lab has already begun building robots at that scale, which could one day be used as diagnostic or environmental sensors. The idea of being able to scavenge energy from the environment to power these kinds of robots is appealing, he says.

“It means you don’t have to put the energy storage on board,” he says. “What we like about this mechanism is that you can take the energy, at least in part, from the environment.”

Here’s a link to and a citation for the paper,

Solvent-induced electrochemistry at an electrically asymmetric carbon Janus particle by Albert Tianxiang Liu, Yuichiro Kunai, Anton L. Cottrill, Amir Kaplan, Ge Zhang, Hyunah Kim, Rafid S. Mollah, Yannick L. Eatmon & Michael S. Strano. Nature Communications volume 12, Article number: 3415 (2021) DOI: https://doi.org/10.1038/s41467-021-23038-7Published 07 June 2021

This paper is open access.

Salt ‘creatures’ could help unclog industrial pipes

I love the video (wish the narrator had a more conversational style rather than the ‘read aloud’ style so many of us adopted in school),

Joel Goldberg’s April 28, 2021 news article (short read) in Science magazine online describes the research (Note: A link has been removed),

Behold the salt monsters. These twisted mineral crystals—formed from the buildup of slightly salty water in power plant pipes—come in many shapes and sizes. But the tiny monsters are a big problem: Each year, they cost the world’s power plants at least $100 billion because workers have to purge the pipes and scrub the crystals from filters.

Now, a solution may be at hand. Engineers can reduce the damage by coating the insides of the pipes with textured, water-repellant [hydrophobic] surfaces …

Here’s a link to and a citation for the paper,

Crystal critters: Self-ejection of crystals from heated, superhydrophobic surfaces by Samantha A. McBride, Henri-Louis Girard, and Kripa K. Varanasi. Science Advances 28 Apr 2021: Vol. 7, no. 18, eabe6960 DOI: 10.1126/sciadv.abe6960

This paper is open access. As research papers go, this is quite readable, from the Introduction (Note: Links have been removed),

Many of the uses for water are intimately familiar to us. Drinking water, wash water, water for agriculture, and even water used for recreation have an omnipresent and essential impact on our lives. However, water’s impact and importance extend far beyond these everyday uses. In many developed countries, thermoelectric power production is one of the largest sources of water consumption (1), where it is used to cool reactors and transport heat. In 2015, 41% of all surface water withdrawals in the United States went toward cooling in thermoelectric power plants (2). Thermoelectric power accounts for 90% of all electricity generated within the United States and encompasses many forms of power production, including nuclear, coal, natural gas, and oil.

There you go.

Litus, a University of Calgary spin-off company, and its lithium extraction process

This company is very secretive. Other than some information about the technology everything else is a mystery. From an April 28, 2021 news item on mining.com,

Litus announced the launching of LiNC, a patent-pending lithium extraction solution initially developed at the University of Calgary in Alberta, Canada.

In a press release, the company said that the nanotechnology composite material within LiNC has very strong ionic affinity and lithium selectivity in the presence of high concentrations of competing ions such as sodium, magnesium and calcium. 

According to Litus, its technology is able to efficiently and sustainably extract more lithium from brine sources than similar methods.

“Demand for lithium is growing at a rate that current production methods and technologies simply can’t meet. Through the application of LiNC, mining companies have an opportunity to not only increase the reserves and production of their existing assets but should be able to open up new sources of lithium that have been either uneconomic or too environmentally sensitive to be practical with previous extraction technology,” the firm’s statement reads.

There is another company which also extracts lithium from the brine in oil wells; their claim to fame is a ‘greener’ extraction method (see my February 23, 2021 posting about Summit Nanotech, which is also located in Calgary, Alberta.)

Getting back to the mysterious Litus,I found this on the About Us section of their homepage,

The Company was formed in 2019 on research originally conducted at the University of Calgary. 

Litus is passionate about developing and supporting technology products that inspire its customers and partners to create energy solutions that are more abundant, more accessible, cleaner, safer, and more efficient. 

The Company is currently applying its leadership in nanotechnology and chemical processing to help companies produce lithium more efficiently and cleanly than previously possible.

THE TEAM

Litus is led by an exceptional group of professional chemists, nanotechnologists, and chemical process engineers, as well as experienced entrepreneurial business professionals. The team has a proven track record of success with both scientific achievements, and in scaling new technologies to become industrially and commercially successful solutions.

You can check out the company’s LinkedIn profile but it’s not particularly useful. There are apparently nine employees but none are identified and the description of the company’s technology is the same as what can be found on their website’s homepage.

Should you be interested in the ‘lithium extraction from brine’ industry, Gabriel Friedman’s February 9, 2021 article for the Financial Post provides some insight into the competitiveness and volatility of this still niche market.

Graphene-based material for high-performance supercapacitors

Researchers from Russia and France have developed a new material, based on graphene, that would allow supercapacitors to store more energy according to a January 15, 2021 news item on Nanowerk,

Scientists of Tomsk Polytechnic University jointly with colleagues from the University of Lille (Lille, France) synthetized a new material based on reduced graphene oxide (rGO) for supercapacitors, energy storage devices. The rGO modification method with the use of organic molecules, derivatives of hypervalent iodine, allowed obtaining a material that stores 1.7 times more electrical energy.

Photo: modified rGO supercapacitor electrodes. Courtesy: Tomsk University

A January 15, 2020 Tomsk Polytechnic University press release (also on EurekAlert), which originated the news item, provides more details,

A supercapacitor is an electrochemical device for storage and release of electric charge. Unlike batteries, they store and release energy several times faster and do not contain lithium.

A supercapacitor is an element with two electrodes separated by an organic or inorganic electrolyte. The electrodes are coated with an electric charge accumulating material. The modern trend in science is to use various materials based on graphene, one of the thinnest and most durable materials known to man. The researchers of TPU and the University of Lille used reduced graphene oxide (rGO), a cheap and available material.

“Despite their potential, supercapacitors are not wide-spread yet. For further development of the technology, it is required to enhance the efficiency of supercapacitors. One of the key challenges here is to increase the energy capacity.

It can be achieved by expanding the surface area of an energy storage material, rGO in this particular case. We found a simple and quite fast method. We used exceptionally organic molecules under mild conditions and did not use expensive and toxic metals,” Pavel Postnikov, Associate Professor of TPU Research School of Chemistry and Applied Biomedical Science and the research supervisor says.

Reduced graphene oxide in a powder form is deposited on electrodes. As a result, the electrode becomes coated with hundreds of nanoscale layers of the substance. The layers tend to agglomerate, in other words, to sinter. To expand the surface area of a material, the interlayer spacing should be increased.

“For this purpose, we modified rGO with organic molecules, which resulted in the interlayer spacing increase. Insignificant differences in interlayer spacing allowed increasing energy capacity of the material by 1.7 times. That is, 1 g of the new material can store 1.7 times more energy in comparison with a pristine reduced graphene oxide,” Elizaveta Sviridova, Junior Research Fellow of TPU Research School of Chemistry and Applied Biomedical Sciences and one of the authors of the article explains.

The reaction proceeded through the formation of active arynes from iodonium salts. They kindle scientists` interest due to their property to form a single layer of new organic groups on material surfaces. The TPU researchers have been developing the chemistry of iodonium salts for many years.

“The modification reaction proceeds under mild conditions by simply mixing the solution of iodonium salt with reduced graphene oxide. If we compare it with other methods of reduced graphene oxide functionalization, we have achieved the highest indicators of material energy capacity increase,” Elizaveta Sviridova says.

Here’s a link to and a citation for the paper,

Aryne cycloaddition reaction as a facile and mild modification method for design of electrode materials for high-performance symmetric supercapacitor by Elizaveta Sviridova, Min Li, Alexandre Barras, Ahmed Addad, Mekhman S.Yusubov, Viktor V. Zhdankin, Akira Yoshimura, Sabine Szunerits, Pavel S. Postnikov, Rabah Boukherroub. Electrochimica Acta Volume 369, 10 February 2021, 137667 DOI: https://doi.org/10.1016/j.electacta.2020.137667

This paper is behind a paywall.

‘Greener’ lithium mining in Canada

A February 19, 2021 article by Pamela Fieber for CBC (Canadian Broadcasting Corporation) news online features news of a Calgary (Alberta) company, Summit Nanotech, and a greener way to mine lithium (Note: A link has been removed),

Amanda Hall was on top of a mountain in Tibet when inspiration struck. 

“I saw a Tibetan monk reach into his robe and pull out an iPhone,” Hall told the Calgary Eyeopener [CBC radio programme].

“If there’s an iPhone at the top of a mountain in Tibet, where isn’t there an iPhone on this planet? And then it just got me thinking about batteries and battery technology and energy and how we store that energy.”

On her return to Calgary, the accomplished geophysicist began looking into a better, greener way to mine lithium — the essential ingredient in lithium-ion batteries, which power electric cars and smartphones.

This led to her founding the company, Summit Nanotech in 2018 and developing nanotechnology, which works with materials at the molecular or atomic level to selectively filter lithium out of the wasted saltwater brine used in oil wells.

It’s completely different from the way lithium is traditionally mined.

Sarah Offin’s November 12, 2020 article for Global TV News offers insight into the technology developed by Hall’s company (Note: Links have been removed),

Since the downturn in the oil and gas industry, there have been repeated calls for Alberta to diversify its economy. The province invests hundreds of millions of dollars every year to help grow both the tech and green energy sectors, industries that could have a bright future in a province rich with talent.

Amanda Hall is a prime example of that. She was able to draw on her experience in resource extraction with Alberta’s oil and gas industry, developing green technology to be used in energy storage.

Hall developed the only female-led mining technology company in the world: Summit Nanotech Corp. Using nanotechnology, Hall and her team say they have created an improved method of lithium-ion resource extraction from produced brine water.

“We’ve come up with a much more elegant approach — I say, feminine, approach — at bringing a resource out of the ground, and then giving it to the electric vehicle sector,” Hall said.

Using sponges developed through nanoscience, Hall and her team have created technology that will allow producers to extract lithium directly from the wellhead without the need for expansive ponds and toxic chemicals. The process is expected to reduce costs and decrease chemical waste by 90 per cent.

The firm’s website touts that its process is the most “green lithium extraction in the world.”

“The sponge has lithium selective cavities in it, just the exact size of a lithium-ion. And so, as if you put a fluid in against this sponge, it will only suck up lithium, nothing else, and it holds on to it. And then when you wash it, you wash the lithium off the sponge just by changing the environment it’s in. So we don’t have to use any acids,” Hall said.

Hall and her team have spent the last two-and-a-half years in the lab perfecting their design and are now building the company’s first full-scale 12-metre tall unit. “It’s our baby, but it’s huge,” Hall said. “It’s a mini-refinery, essentially.”

That “mini-refinery” will then be sent via shipping container to the first of the company’s three pilot partners: Lithium Chile.

The other two partners are Saskatchewan-based Prairie Lithium and 3 Proton Lithium (3PL) Operating Inc. in Nevada.

For anyone interested in the business and investment aspects (there’s mention of Elon Musk in both stories) check out Fieber’s February 19, 2021 article and Offin’s November 12, 2020 article.

You can find Summit Nanotech here. I found a little more information about the company’s technology on the Lithium webpage,

denaLi 1.0
Direct Lithium Extraction
(DLE) Process

Summit Nanotech has designed an innovative new method to generate battery grade lithium compounds from brine fluids, named denaLi. This process is the most green lithium extraction technology in the world. Lithium carbonate and lithium hydroxide can be sold at market value to supply the growing demand from electric vehicle battery manufacturers. 

Interconnected modules using nanoporous membranes in a unique arrangement are synthesized with specific filtration functions. Carbon dioxide is used to initiate end product precipitation. Discrete power generation modules are selected to work together to harvest and store available geothermal, solar, wind, and hydroelectric power from the system’s environment.

Prairie Lithium, the Saskatchewan-based company mentioned in Offin’s article, co-founded a joint venture specifically dedicated to lithium extraction from brine (to begin with) in 2020 according to Jonathan Guignard in a June 3, 2020 article for Global TV news (Note: Links have been removed),

Saskatchewan will soon be home to a new lithium production project.

The Prairie-LiEP Critical Mineral (PLCM) joint venture is being undertaken by Prairie Lithium Corp. and LiEP Energy Ltd [headquarted in Calgary, Alberta].

Their two-stage pilot project will produce lithium hydroxide from some of the province’s oilfield brines.

The first stage of the project is based in Regina and is set to being in July. The second stage is set for the second half of 2021, with field operations in southern parts of the province.

“PLCM Joint Venture is excited to begin Stage 1 of the pilot operation in Saskatchewan this summer,” said Prairie president and CEO Zach Maurer and LiEP president and CEO Haafiz Hasham.

I can’t find any mention of the PLCM joint venture on the Prairie Lithium website but there is what appears to be a June 3, 2020 news release announcing the venture on the LiEP Energy website but there is no further information on that website.

On another front, Lithium Chile, which seems to be headquartered in Calgary with extensive lithium mining projects in Chile, has a brief mention of their partnership with Summit Nanotech in a December 24, 2020 posting (on the News webpage) by Steve (Cochrane; president and chief executive officer),

Lastly our partnership with Summit continues to move forward and we are very happy to be working with them. I have attached our recently negotiated LOI [letter of intent] for our JV [joint venture] pilot project in Chile. We should have the definitive agreement signed early in the new year. They plan to have their pilot unit completed and shipped by July of 2021 so a planned test is scheduled for late summer next year. This gives us the time to get back on one or more of our lithium prospects to prepare for our pilot project. They continue to see great results in the lab and hope this is the breakthrough we all want to see for an efficient cost and environmentally effective method of producing lithium from brines.

I cannot find any further mention on the Lithium Chile website about their joint venture with Summit Nanotech.

The big question is whether or not this technology can be scaled for industrial use. I wish them good luck with the effort.

All this talk about lithium extraction and other natural resource extraction brought to mind Harold Innis and his staples theory of Canadian history, culture, and economy. From the Harold Innis Wikipedia entry (Note: Links have been removed),

Harold Adams Innis FRSC (1894 – 1952) was a Canadian professor of political economy at the University of Toronto and the author of seminal works on media, communication theory, and Canadian economic history. He helped develop the staples thesis, [emphasis mine] which holds that Canada’s culture, political history, and economy have been decisively influenced by the exploitation and export of a series of “staples” such as fur, fishing, lumber, wheat, mined metals [emphasis mine], and coal. The staple thesis dominated economic history in Canada from the 1930s to 1960s, and continues to be a fundamental part of the Canadian political economic tradition.[8]

There you have it.

Carbon nanotubes (CNTs) in 466 colours

Caption: A color map illustrates the inherent colors of 466 types of carbon nanotubes with unique (n,m) designations based their chiral angle and diameter. Credit: Image courtesy of Kauppinen Group/Aalto University

This is, so to speak, a new angle on carbon nanotubes (CNTs). It’s also the first time I’ve seen two universities place identical news releases on EurekAlert under their individual names.

From the Dec. 14, 2020 Rice University (US) news release or the Dec. 14, 2020 Aalto University (Finland) press release on EurekAlert,

Nanomaterials researchers in Finland, the United States and China have created a color atlas for 466 unique varieties of single-walled carbon nanotubes.

The nanotube color atlas is detailed in a study in Advanced Materials about a new method to predict the specific colors of thin films made by combining any of the 466 varieties. The research was conducted by researchers from Aalto University in Finland, Rice University and Peking University in China.

“Carbon, which we see as black, can appear transparent or take on any color of the rainbow,” said Aalto physicist Esko Kauppinen, the corresponding author of the study. “The sheet appears black if light is completely absorbed by carbon nanotubes in the sheet. If less than about half of the light is absorbed in the nanotubes, the sheet looks transparent. When the atomic structure of the nanotubes causes only certain colors of light, or wavelengths, to be absorbed, the wavelengths that are not absorbed are reflected as visible colors.”

Carbon nanotubes are long, hollow carbon molecules, similar in shape to a garden hose but with sides just one atom thick and diameters about 50,000 times smaller than a human hair. The outer walls of nanotubes are made of rolled graphene. And the wrapping angle of the graphene can vary, much like the angle of a roll of holiday gift wrap paper. If the gift wrap is rolled carefully, at zero angle, the ends of the paper will align with each side of the gift wrap tube. If the paper is wound carelessly, at an angle, the paper will overhang on one end of the tube.

The atomic structure and electronic behavior of each carbon nanotube is dictated by its wrapping angle, or chirality, and its diameter. The two traits are represented in a “(n,m)” numbering system that catalogs 466 varieties of nanotubes, each with a characteristic combination of chirality and diameter. Each (n,m) type of nanotube has a characteristic color.

Kauppinen’s research group has studied carbon nanotubes and nanotube thin films for years, and it previously succeeded in mastering the fabrication of colored nanotube thin films that appeared green, brown and silver-grey.

In the new study, Kauppinen’s team examined the relationship between the spectrum of absorbed light and the visual color of various thicknesses of dry nanotube films and developed a quantitative model that can unambiguously identify the coloration mechanism for nanotube films and predict the specific colors of films that combine tubes with different inherent colors and (n,m) designations.

Rice engineer and physicist Junichiro Kono, whose lab solved the mystery of colorful armchair nanotubes in 2012, provided films made solely of (6,5) nanotubes that were used to calibrate and verify the Aalto model. Researchers from Aalto and Peking universities used the model to calculate the absorption of the Rice film and its visual color. Experiments showed that the measured color of the film corresponded quite closely to the color forecast by the model.

The Aalto model shows that the thickness of a nanotube film, as well as the color of nanotubes it contains, affects the film’s absorption of light. Aalto’s atlas of 466 colors of nanotube films comes from combining different tubes. The research showed that the thinnest and most colorful tubes affect visible light more than those with larger diameters and faded colors.

“Esko’s group did an excellent job in theoretically explaining the colors, quantitatively, which really differentiates this work from previous studies on nanotube fluorescence and coloration,” Kono said.

Since 2013, Kono’s lab has pioneered a method for making highly ordered 2D nanotube films. Kono said he had hoped to supply Kauppinen’s team with highly ordered 2D crystalline films of nanotubes of a single chirality.

“That was the original idea, but unfortunately, we did not have appropriate single-chirality aligned films at that time,” Kono said. “In the future, our collaboration plans to extend this work to study polarization-dependent colors in highly ordered 2D crystalline films.”

The experimental method the Aalto researchers used to grow nanotubes for their films was the same as in their previous studies: Nanotubes grow from carbon monoxide gas and iron catalysts in a reactor that is heated to more than 850 degrees Celsius. The growth of nanotubes with different colors and (n,m) designations is regulated with the help of carbon dioxide that is added to the reactor.

“Since the previous study, we have pondered how we might explain the emergence of the colors of the nanotubes,” said Nan Wei, an assistant research professor at Peking University who previously worked as a postdoctoral researcher at Aalto. “Of the allotropes of carbon, graphite and charcoal are black, and pure diamonds are colorless to the human eye. However, now we noticed that single-walled carbon nanotubes can take on any color: for example, red, blue, green or brown.”

Kauppinen said colored thin films of nanotubes are pliable and ductile and could be useful in colored electronics structures and in solar cells.

“The color of a screen could be modified with the help of a tactile sensor in mobile phones, other touch screens or on top of window glass, for example,” he said.

Kauppinen said the research can also provide a foundation for new kinds of environmentally friendly dyes.

Here’s a link to and a citation for the paper,

Colors of Single‐Wall Carbon Nanotubes by Nan Wei, Ying Tian, Yongping Liao, Natsumi Komatsu, Weilu Gao, Alina Lyuleeva‐Husemann, Qiang Zhang, Aqeel Hussain, Er‐Xiong Ding, Fengrui Yao, Janne Halme. Kaihui Liu, Junichiro Kono, Hua Jiang, Esko I. Kauppinen. Advanced Materials DOI: https://doi.org/10.1002/adma.202006395 First published: 14 December 2020

Thi8s paper is open access.