Tag Archives: US Dept. of Energy

Studying corrosion from the other side

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Corrosion can be beautiful as well as destructive,

Typically, the process of corrosion has been studied from the metal side of the equation - See more at: http://www.anl.gov/articles/core-corrosion#sthash.ZPqFF13I.dpuf. Courtesy of the Argonne National Laboratory

Typically, the process of corrosion has been studied from the metal side of the equation – See more at: http://www.anl.gov/articles/core-corrosion#sthash.ZPqFF13I.dpuf. Courtesy of the Argonne National Laboratory

A Feb. 18, 2014 news item on Nanowerk expands on the theme of corrosion as destruction (Note: Links have been removed),

Anyone who has ever owned a car in a snowy town – or a boat in a salty sea – can tell you just how expensive corrosion can be.

One of the world’s most common and costly chemical reactions, corrosion happens frequently at the boundaries between water and metal surfaces. In the past, the process of corrosion has mostly been studied from the metal side of the equation.

However, in a new study (“Chloride ions induce order-disorder transition at water-oxide interfaces”), scientists at the Center for Nanoscale Materials at the U.S. Department of Energy’s Argonne National Laboratory investigated the problem from the other side, looking at the dynamics of water containing dissolved ions located in the regions near a metal surface.

The Feb. 14, 2014 Argonne National Laboratory news release by Jared Sagoff, which originated the news item, describes how the scientists conducted their research,

A team of researchers led by Argonne materials scientist Subramanian Sankaranarayanan simulated the physical and chemical dynamics of dissolved ions in water at the atomic level as it corrodes metal oxide surfaces. “Water-based solutions behave quite differently near a metal or oxide surface than they do by themselves,” Sankaranarayanan said. “But just how the chemical ions in the water interact with a surface has been an area of intense debate.”

Under low-chlorine conditions, water tends to form two-dimensional ordered layers near solid interfaces because of the influence of its strong hydrogen bonds. However, the researchers found that increasing the proportion of chlorine ions above a certain threshold causes a change in which the solution loses its ordered nature near the surface and begins to act similar to water away from the surface. This transition, in turn, can increase the rate at which materials corrode as well as the freezing temperature of the solution.

This switch between an ordered and a disordered structure near the metal surface happens incredibly quickly, in just fractions of a nanosecond. The speed of the chemical reaction necessitates the use of high-performance computers like Argonne’s Blue/Gene Q supercomputer, Mira.

To further explore these electrochemical oxide interfaces with high-performance computers, Sankaranarayanan and his colleagues from Argonne, Harvard University and the University of Missouri have also been awarded 40 million processor-hours of time on Mira.

“Having the ability to look at these reactions in a more powerful simulation will give us the opportunity to make a more educated guess of the rates of corrosion for different scenarios,” Sankaranarayanan said. Such studies will open up for the first time fundamental studies of corrosion behavior and will allow scientists to tailor materials surfaces to improve the stability and lifetime of materials.

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

Chloride ions induce order-disorder transition at water-oxide interfaces by Sanket Deshmukh, Ganesh Kamath, Shriram Ramanathan, and Subramanian K. R. S. Sankaranarayanan. Phys. Rev. E 88 (6), 062119 (2013) [5 pages]

This article is behind a paywall on both the primary site and the beta site (the American Physical Society is testing a new website for its publications).

Mixing and matching your nanoparticles

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An Oct. 20, 2013 Brookhaven National Laboratory (BNL; US Dept. of Energy) news release (also on EurekAlert) describes a technique for combining different kinds of nanoparticles into a single nanocomposite,

Scientists at the U.S. Department of Energy’s Brookhaven National Laboratory have developed a general approach for combining different types of nanoparticles to produce large-scale composite materials. The technique, described in a paper published online by Nature Nanotechnology on October 20, 2013, opens many opportunities for mixing and matching particles with different magnetic, optical, or chemical properties to form new, multifunctional materials or materials with enhanced performance for a wide range of potential applications.

The approach takes advantage of the attractive pairing of complementary strands of synthetic DNA—based on the molecule that carries the genetic code in its sequence of matched bases known by the letters A, T, G, and C. After coating the nanoparticles with a chemically standardized “construction platform” and adding extender molecules to which DNA can easily bind, the scientists attach complementary lab-designed DNA strands to the two different kinds of nanoparticles they want to link up. The natural pairing of the matching strands then “self-assembles” the particles into a three-dimensional array consisting of billions of particles. Varying the length of the DNA linkers, their surface density on particles, and other factors gives scientists the ability to control and optimize different types of newly formed materials and their properties.

The news release details some of the challenges the researchers faced,

… the scientists explored the effect of particle shape. “In principle, differently shaped particles don’t want to coexist in one lattice,” said Gang [Brookhaven physicist Oleg Gang]. “They either tend to separate into different phases like oil and water refusing to mix or form disordered structures.” The scientists discovered that DNA not only helps the particles mix, but it can also improve order for such systems when a thicker DNA shell around the particles is used.

They also investigated how the DNA-pairing mechanism and other intrinsic physical forces, such as magnetic attraction among particles, might compete during the assembly process. For example, magnetic particles tend to clump to form aggregates that can hinder the binding of DNA from another type of particle. “We show that shorter DNA strands are more effective at competing against magnetic attraction,” Gang said.

For the particular composite of gold and magnetic nanoparticles they created, the scientists discovered that applying an external magnetic field could “switch” the material’s phase and affect the ordering of the particles. “This was just a demonstration that it can be done, but it could have an application—perhaps magnetic switches, or materials that might be able to change shape on demand,” said Zhang [[Yugang Zhang, first author of the paper].

The third fundamental factor the scientists explored was how the particles were ordered in the superlattice arrays: Does one type of particle always occupy the same position relative to the other type—like boys and girls sitting in alternating seats in a movie theater—or are they interspersed more randomly? “This is what we call a compositional order, which is important for example for quantum dots because their optical properties—e.g., their ability to glow—depend on how many gold nanoparticles are in the surrounding environment,” said Gang. “If you have compositional disorder, the optical properties would be different.” In the experiments, increasing the thickness of the soft DNA shells around the particles increased compositional disorder.

These fundamental principles give scientists a framework for designing new materials. The specific conditions required for a particular application will be dependent on the particles being used, Zhang emphasized, but the general assembly approach would be the same.

Said Gang, “We can vary the lengths of the DNA strands to change the distance between particles from about 10 nanometers to under 100 nanometers—which is important for applications because many optical, magnetic, and other properties of nanoparticles depend on the positioning at this scale. We are excited by the avenues this research opens up in terms of future directions for engineering novel classes of materials that exploit collective effects and multifunctionality.”

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

A general strategy for the DNA-mediated self-assembly of functional nanoparticles into heterogeneous systems by Yugang Zhang, Fang Lu, Kevin G. Yager, Daniel van der Lelie, & Oleg Gang. Nature Nanotechnology (2013) doi:10.1038/nnano.2013.209 Published online 20 October 2013.

This article can be viewed/previewed on ReadCube or purchased.

Smarter ‘smart’ windows

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It seems to me we may have to find a new way to discuss ‘smart’ windows as there’s only one more category after the comparative  ‘smarter’ and that’s the superlative ‘smartest’. Lawrence Berkeley National Laboratory (Berkeley Lab), please, let’s stop the madness now! That said, the Berkeley Lab issued an Aug. 14, 2013 news release  (also on EurekAlert) about it’s latest work on raising the IQ of smart windows,

Researchers at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have designed a new material to make smart windows even smarter. The material is a thin coating of nanocrystals embedded in glass that can dynamically modify sunlight as it passes through a window. Unlike existing technologies, the coating provides selective control over visible light and heat-producing near-infrared (NIR) light, so windows can maximize both energy savings and occupant comfort in a wide range of climates.

…

Milliron’s research group is already well known for their smart-window technology that blocks NIR without blocking visible light. The technology hinges on an electrochromic effect, where a small jolt of electricity switches the material between NIR-transmitting and NIR-blocking states. This new work takes their approach to the next level by providing independent control over both visible and NIR light. The innovation was recently recognized with a 2013 R&D 100 Award and the researchers are in the early stages of commercializing their technology.

Independent control over NIR light means that occupants can have natural lighting indoors without unwanted thermal gain, reducing the need for both air-conditioning and artificial lighting. The same window can also be switched to a dark mode, blocking both light and heat, or to a bright, fully transparent mode.

“We’re very excited about the combination of unique optical function with the low-cost and environmentally friendly processing technique,” said Llordés, a project scientist working with Milliron. “That’s what turns this ‘universal smart window’ concept into a promising competitive technology.”

Here’s the specific technology that’s been developed, from the news release,

At the heart of their technology is a new “designer” electrochromic material, made from nanocrystals of indium tin oxide embedded in a glassy matrix of niobium oxide. The resulting composite material combines two distinct functionalities—one providing control over visible light and the other, control over NIR—but it is more than the sum of its parts. The researchers found a synergistic interaction in the tiny region where glassy matrix meets nanocrystal that increases the potency of the electrochromic effect, which means they can use thinner coatings without compromising performance. The key is that the way atoms connect across the nanocrystal-glass interface causes a structural rearrangement in the glass matrix. The interaction opens up space inside the glass, allowing charge to move in and out more readily. Beyond electrochromic windows, this discovery suggests new opportunities for battery materials where transport of ions through electrodes can be a challenge.

I notice they’re using indium, one of the ‘rare earths’. Last I heard, China, one of the main sources for ‘rare earths’, was limiting its exports so this seems like an odd choice of material. Perhaps now they’ve proved this can be done,  they’ll research for easily available substitutes. Here’s a link to and a citation for the published paper,

Tunable near-infrared and visible-light transmittance in nanocrystal-in-glass composites by Anna Llordés, Guillermo Garcia, Jaume Gazquez, & Delia J. Milliron. Nature 500, 323–326 (15 August 2013) doi:10.1038/nature12398 Published online 14 August 2013

Finally, the researchers have provided an illustration of indium tin oxide nanocrystals,

Nanocrystals of indium tin oxide (shown here in blue) embedded in a glassy matrix of niobium oxide (green) form a composite material that can switch between NIR-transmitting and NIR-blocking states with a small jolt of electricity. A synergistic interaction in the region where glassy matrix meets nanocrystal increases the potency of the electrochromic effect. Courtesy Berkeley Lab

Nanocrystals of indium tin oxide (shown here in blue) embedded in a glassy matrix of niobium oxide (green) form a composite material that can switch between NIR-transmitting and NIR-blocking states with a small jolt of electricity. A synergistic interaction in the region where glassy matrix meets nanocrystal increases the potency of the electrochromic effect. Courtesy Berkeley Lab

Gold nanoparticles and the air that you breathe

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Scientists at the (US Dept. of Energy) Brookhaven National Laboratory can turn gold nanoparticles into catalysts using a room temperature process. From the June 11, 2013 news item on ScienceDaily,

Gold bars may signify great wealth, but the precious metal packs a much more practical punch when shrunk down to just billionths of a meter. Unfortunately, unlocking gold’s potential often requires complex synthesis techniques that produce delicate structures with extreme sensitivity to heat.

Now, scientists at the U.S. Department of Energy’s Brookhaven National Laboratory have discovered a process of creating uniquely structured gold-indium nanoparticles that combine high stability, great catalytic potential, and a simple synthesis process. The new nanostructures — detailed online June 10 in the Proceedings of the National Academy of Sciences — might enhance many different commercial and industrial processes, including acting as an efficient material for catalytic converters in cars.

“We discovered a room-temperature process that transforms a simple alloy into a nanostructure with remarkable properties,” said physicist Eli Sutter, lead author on the study. “By exposing the gold-indium alloy nanoparticles to air, ambient oxygen was able to drive an oxidation reaction that converted them into an active core-shell structure.”

The Brookhaven National Laboratory June 11, 2013 news release, which originated the news item, explains the issues with gold nanoparticles and how the ‘room temperature’ discovery was made,

The Brookhaven Lab researchers were studying oxidation processes through which metals and alloys combine with oxygen when they made the discovery. For this study, they examined alloys of a noble metal and a non-noble metal through a remarkably simple reaction technique: giving gold-indium nanoparticles a little room to breathe. Once nanoparticles of the metal alloy were exposed to oxygen, highly reactive shells of gold-indium oxide formed across their surfaces.

“Conventional wisdom would say that oxidation should push the gold atoms into the center while pulling the less noble indium to the surface, creating a noble metal core that is surrounded by a shell of non-reactive indium-oxide,” Peter Sutter said. “Instead, the oxygen actually penetrated the alloy. After oxidation, the alloy core of the nanoparticles was encapsulated by a newly formed thin shell of mixed gold-indium oxide.”

Trapping gold in the amorphous oxide shell retains its catalytic properties and prevents the gold from sintering and becoming inert. The new nanostructures proved capable of converting oxygen and carbon monoxide into carbon dioxide, demonstrating their activity as a catalyst.

“The indium and gold in the shell are not mobile, but are frozen in the amorphous, oxide,” Eli Sutter said. “Importantly, the structural integrity holds without sintering at temperatures of up to 300 degrees Celsius, making these remarkably resilient compared to other gold nanocatalysts.”

The research was conducted at Brookhaven Lab’s Center for Functional Nanomaterials (CFN), whose unique facilities for nanoscale synthesis and characterization proved central to the discovery of this new process.

“The CFN brings a wide range of state-of-the-art instruments and expertise together under one roof, accelerating research and facilitating collaboration,” Eli Sutter said. “We used transmission electron microscopy to characterize the structures and their composition, x-ray photoelectron spectroscopy to determine the chemical bonding at the surface, and ion-scattering spectroscopy to identify the outermost atoms of the nanoparticle shell.”

Further investigations will help determine the properties of the gold-indium oxide particles in different catalytic reactions, and the same oxidation process will be applied to other metal alloys to create an entire family of new functional materials.

You can find a citation and a link to the researchers’ paper if you click on the ScienceDaily news item link earlier in this posting.

Sifting through Twitter with your computer cluster of more than 600 nodes named Olympus—one of the Top 500 fastest supercomputers in the world.

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Here are two (seemingly) contradictory pieces of information (1) the US Library of Congress takes over 24 hours to complete a single search of tweets archived from 2006 – 2010, according to my Jan. 16, 2013 posting, and (2) Court (Courtney) Corley, a data scientist at the US Dept. of Energy’s Pacific Northwest National Laboratory (PNNL), has a system (SALSA; SociAL Sensor Analytics) that analyzes billions of tweets in seconds. It’s a little hard to make sense out of these two very different perspectives on accessing data from tweets.

The news from Corley and the PNNL is more recent and, before I speculate further, here’s a bit more about Corley’s work, from the June 6, 2013 PNNL news release (also on EurekAlert)

If you think keeping up with what’s happening via Twitter, Facebook and other social media is like drinking from a fire hose, multiply that by 7 billion – and you’ll have a sense of what Court Corley wakes up to every morning.

Corley, a data scientist at the Department of Energy’s Pacific Northwest National Laboratory, has created a powerful digital system capable of analyzing billions of tweets and other social media messages in just seconds, in an effort to discover patterns and make sense of all the information. His social media analysis tool, dubbed “SALSA” (SociAL Sensor Analytics), combined with extensive know-how – and a fair degree of chutzpah – allows someone like Corley to try to grasp it all.

“The world is equipped with human sensors – more than 7 billion and counting. It’s by far the most extensive sensor network on the planet. What can we learn by paying attention?” Corley said.

Among the payoffs Corley envisions are emergency responders who receive crucial early information about natural disasters such as tornadoes; a tool that public health advocates can use to better protect people’s health; and information about social unrest that could help nations protect their citizens. But finding those jewels amidst the effluent of digital minutia is a challenge.

“The task we all face is separating out the trivia, the useless information we all are blasted with every day, from the really good stuff that helps us live better lives. There’s a lot of noise, but there’s some very valuable information too.”

I was getting a little worried when I saw the bit about separating useless information from the good stuff since that can be a very personal choice. Thankfully, this followed,

One person’s digital trash is another’s digital treasure. For example, people known in social media circles as “Beliebers,” named after entertainer Justin Bieber, covet inconsequential tidbits about Justin Bieber, while “non-Beliebers” send that data straight to the recycle bin.

The amount of data is mind-bending. In social media posted just in the single year ending Aug. 31, 2012, each hour on average witnessed:

  • 30 million comments
  • 25 million search queries
  • 98,000 new tweets
  • 3.8 million blog views
  • 4.5 million event invites
  • 7.1 million photos uploaded
  • 5.5 million status updates
  • The equivalent of 453 years of video watched

Several firms routinely sift posts on LinkedIn, Facebook, Twitter, YouTube and other social media, then analyze the data to see what’s trending. These efforts usually require a great deal of software and a lot of person-hours devoted specifically to using that application. It’s what Corley terms a manual approach.

Corley is out to change that, by creating a systematic, science-based, and automated approach for understanding patterns around events found in social media.

It’s not so simple as scanning tweets. Indeed, if Corley were to sit down and read each of the more than 20 billion entries in his data set from just a two-year period, it would take him more than 3,500 years if he spent just 5 seconds on each entry. If he hired 1 million helpers, it would take more than a day.

But it takes less than 10 seconds when he relies on PNNL’s Institutional Computing resource, drawing on a computer cluster with more than 600 nodes named Olympus, which is among the Top 500 fastest supercomputers in the world.

“We are using the institutional computing horsepower of PNNL to analyze one of the richest data sets ever available to researchers,” Corley said.

At the same time that his team is creating the computing resources to undertake the task, Corley is constructing a theory for how to analyze the data. He and his colleagues are determining baseline activity, culling the data to find routine patterns, and looking for patterns that indicate something out of the ordinary. Data might include how often a topic is the subject of social media, who is putting out the messages, and how often.

Corley notes additional challenges posed by social media. His programs analyze data in more than 60 languages, for instance. And social media users have developed a lexicon of their own and often don’t use traditional language. A post such as “aw my avalanna wristband @Avalanna @justinbieber rip angel pic.twitter.com/yldGVV7GHk” poses a challenge to people and computers alike.

Nevertheless, Corley’s program is accurate much more often than not, catching the spirit of a social media comment accurately more than three out of every four instances, and accurately detecting patterns in social media more than 90 percent of the time.

Corley’s educational background may explain the interest in emergency responders and health crises mentioned in the early part of the news release (from Corley’s PNNL webpage),

B.S. Computer Science from University of North Texas; M.S. Computer Science from University of North Texas; Ph.D. Computer Science and Engineering from University of North Texas; M.P.H (expected 2013) Public Health from University of Washington.

The reference to public health and emergency response is further developed, from the news release,

Much of the work so far has been around public health. According to media reports in China, the current H7N9 flu situation in China was highlighted on Sina Weibo, a China-based social media platform, weeks before it was recognized by government officials. And Corley’s work with the social media working group of the International Society for Disease Surveillance focuses on the use of social media for effective public health interventions.

In collaboration with the Infectious Disease Society of America and Immunizations 4 Public Health, he has focused on the early identification of emerging immunization safety concerns.

“If you want to understand the concerns of parents about vaccines, you’re never going to have the time to go out there and read hundreds of thousands, perhaps millions of tweets about those questions or concerns,” Corley said. “By creating a system that can capture trends in just a few minutes, and observe shifts in opinion minute to minute, you can stay in front of the issue, for instance, by letting physicians in certain areas know how to customize the educational materials they provide to parents of young children.”

Corley has looked closely at reaction to the vaccine that protects against HPV, which causes cervical cancer. The first vaccine was approved in 2006, when he was a graduate student, and his doctoral thesis focused on an analysis of social media messages connected to HPV. He found that creators of messages that named a specific drug company were less likely to be positive about the vaccine than others who did not mention any company by name.

Other potential applications include helping emergency responders react more efficiently to disasters like tornadoes, or identifying patterns that might indicate coming social unrest or even something as specific as a riot after a soccer game. More than a dozen college students or recent graduates are working with Corley to look at questions like these and others.

As to why the US Library of Congress requires 24 hours to search one term in their archived tweets and Corley and the PNNL require seconds to sift through two years of tweets, only two possibilities come to my mind. (1) Corley is doing a stripped down version of an archival search so his searches are not comparable to the Library of Congress searches or (2) Corley and the PNNL have far superior technology.

A ‘graphite today, graphene tomorrow’ philosophy from Focus Graphite

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Focus Graphite, a Canadian company with the tag line ‘Think Graphite today, Think Graphene tomorrow’, is making a bit of splash this month (April 2013) with its announcement of three deals (two joint ventures and the commissioning of their pilot plant) and it’s only April 17.

The most recent is the pilot plant announcement, from Focus Graphite’s Apr. 17, 2013 press release,

Focus Graphite Inc. (TSX-V:FMS)(OTCQX:FCSMF)(FRANKFURT:FKC) (“Focus” or the “Company”) is pleased to report the commissioning of its pilot plant and the start-up of circuit testing for the production of high-grade graphite concentrates from the Company’s wholly-owned Lac Knife, Québec graphite project.

The principal objectives of the pilot plant testwork are to confirm the results from Phase II bench scale Locked Cycle Tests (LCT)*; to assess the technical viability and operational performance of the processing plant design; to generate tailings for environmental testing, and; to produce a range of graphite raw materials for customer assessments and for further upgrading.

The Lac Knife project pilot plant was designed and built and is being operated by SGS Canada Inc. (“SGS”) in Lakefield, Ontario. The testing is expected to last 4-6 weeks.

….

The highlights of those tests conducted by SGS confirmed:-       The average amount of graphite flake recovered from the core samples in the Phase II LCT increased to 92.2% compared with a recovery of 84.7% graphite flake in the Phase I LCT;

–       The proportion of large flakes (+80 mesh) in the graphite concentrates ranged between 35% and 58%;

–       The carbon content of graphite concentrates produced from the four (4) composites averaged 96.6 %C, including the fine flake fraction (-200 mesh), a 4.6% increase over Phase I LCT completed in mid-2012.

Final results for Phase II LCT including for the two composite drill core samples of massive graphite mineralisation are pending.

* A locked cycle test is a repetitive batch flotation test conducted to assess flow sheet design. It is the preferred method for arriving at a metallurgical projection from laboratory testing. The final cycles of the test are designed to simulate a continuous, stable flotation circuit.

There’s also the announcement of a joint venture between Grafoid (a company where, I believe, 40% is owned by Focus Graphite) with the University of Waterloo, from the Apr. 17, 2013 news item on Azonano,

Focus Graphite Inc. on behalf of Grafoid Inc. (“Grafoid”) is pleased to announce the signing of a two-year R&D agreement between Grafoid Inc. and the University of Waterloo to investigate and develop a graphene-based composite for electrochemical energy storage for the automotive and/or portable electronics sectors.

Gary Economo, President and CEO of Focus Graphite Inc. and Grafoid Inc., said the objective of the agreement is to research and develop patentable applications using Grafoid’s unique investment which derives graphene from raw, graphite ore to target specialty high value graphene derivatives ranging from sulfur graphene to nanoporous graphene foam.

…

“Today’s announcement marks Grafoid’s fifth publicly declared graphene development project with a major academic or corporate institution, and the third related directly to a next generation green technology or renewable energy development project,” Mr. Economo said.

It follows R&D partnering projects announced with Rutgers University’s AMIPP, CVD Equipment Corporation, with Hydro-Quebec’s research institute, IREQ, and with British Columbia-based CapTherm Systems, an advanced thermal management technologies developer and producer.

Focus Graphite’s Apr. 16, 2013 press release, which originated the news item on Azonano, provides some context for the intense worldwide interest in graphene and the business imperatives,

Alternative Energy & Graphene:

The quest for alternative energy sources is one of the most important and exciting challenges facing science and technology in the 21st century. Environmentally-friendly, efficient and sustainable energy generation and usage have become large efforts for advancing human societal needs.  Graphene is a pure form of carbon with powerful characteristics which can bring about success in portable, stationary and transportation applications in high energy demanding areas in which electrochemical energy storage and conversion devices such as batteries, fuel cells and electrochemical supercapacitors  are the necessary devices.

Electrochemical Supercapacitors:

Supercapacitors, a zero-emission energy storage system, have a number of high-impact characteristics, such as fast charging, long charge-discharge cycles and broad operating temperature ranges, currently used or heavily researched in hybrid or electrical vehicles, electronics, aircrafts, and smart grids for energy storage. The US Department of Energy has assigned the same importance to supercapacitors and batteries. There is much research looking at combining electrochemical supercapacitors with battery systems or fuel cells.

Fuel Cells:

A fuel cell is a zero-emission source of power, and the only byproduct of a fuel cell is water. Some fuel cells use natural gas or hydrocarbons as fuel, but even those produce far less emissions than conventional sources. As a result, fuel cells eliminate or at least vastly reduce the pollution and greenhouse gas emissions caused by burning fossil fuels, and since they are also quiet in operation, they also reduce noise pollution. Fuel cells are more efficient than combustion engines as they generate electricity electrochemically. Since they can produce electricity onsite, the waste heat produced can also be used for heating purposes. Small fuel cells are already replacing batteries in portable products.

Toyota is planning to launch fuel cell cars in 2015, and has licensed its fuel cell vehicle technology to Germany’s BMW AG. BMW will use the technology to build a prototype vehicle by 2015, with plans for a market release around 2020.

By 2020, market penetration could rise as high as 1.2 million fuel cell vehicles, which would represent 7.6% of the total U.S. automotive market. Other fuel cell end users are fork lift and mining industries which continuously add profits to this growing industry.

Proton or polymer exchange membranes (PEM) have become the dominant fuel cell technology in the automotive market.

The U.S. Department of Energy has set fuel cell performance standards for 2015. As of today, no technologies under development have been able to meet the DOE’s  targets for performance and cost.

As I am from British Columbia and it was where* the first joint venture deal signed in April, here’s a bit more from Focus Graphite’s Apr. 9, 2013 press release,

Focus Graphite Inc. (TSX-V:FMS)(OTCQX:FCSMF)(FRANKFURT:FKC) on behalf of Grafoid Inc., announced today Grafoid’s joint venture development agreement with Coquitlam, British Columbia-based CapTherm Systems Inc. to develop and commercialize next generation, multiphase thermal management systems for electric vehicle (EV) battery and light emitting diode (LED) technologies.

CapTherm Systems Inc – Progressive Thermal Management is a thermal management/cooling company specializing in personal computer, server, LED, and electric vehicle cooling systems. It develops and commercializes proprietary, next-generation high-power electronics cooling technologies.

Its multiphase cooling technologies represent the core of its products that harness the power of latent heat from vaporization.

Under the terms of the agreement, Grafoid Inc., a company invested in the production of high-energy graphene and the development of graphene industrial applications will supply both materials and its science for adapting graphene to CapTherm’s existing EV and LED cooling systems.

Focus Graphite is a Canadian company, you can find more information on their website and the same for Grafoid and SGS Canada, and CapTherm Systems.

I have previously mentioned Focus Graphite in a Nov. 27, 2012 posting about their deal with Hydro Québec’s research institute, IREQ. I have also mentioned graphite mining in Canada with regard to the Northern Graphite Corporation and its Bissett Creek mine (my July 25, 2011 posting and my Feb. 6, 2012 posting). Apparently, Canada has high quality, large graphic flakes.

* ‘where’ added to sentence on Feb. 23, 2015.

Smart wall or smart window? Ravenbrick brings one to the market in 2013

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Alex Davies posted a July 10, 2012 article on the Treehugger website about a smart window/wall system from RavenBrick. From the article (Note: I have removed links),

The RavenWindow from RavenBrick changes its tint in response to temperature, so it blocks sunlight entering a building after a set temperature has been reached. Combine it with a layer of insulating materials that store heat during the day and release it at night, and you’ve got the RavenSkin Smart Wall System.

Here’s a little more about the RavenWindow from the company’s Project Portfolio page,

RavenBrick has installed their RavenWindow product at the [US] Department of Energy’s National Renewable Energy Lab in Golden Colorado. This LEED platinum building was designed to use the most energy efficient products available. This installation, on the executive floor, is the first of three installations that will be done at NREL.

RavenWindow at NREL in the clear state viewed from the inside (from the RavenBrick website)

 

RavenWindow at NREL in the tinted state viewed from the inside (from the RavenBrick website)

Then, here is the view of the tinted windows from the outside,

RavenWindow at NREL in the tinted state viewed from outside (from the RavenBrick website)

They do give a fairly simple explanation of the technology, from the company’s The Technology page,

RavenBrick’s smart window systems are changing the rules of energy efficent design by doing something that previous generations of building materials simply couldn’t: letting the sun’s heat into the building when you need it, and keeping it out when you don’t.

Our thermochromic filters utilize advances in nanotechnology, pioneered and patented by RavenBrick, to transition from a transparent to a reflective state in response to changes in the outside temperature. This transition allows a building to use the sun as a source of free heat on cold days and block solar heat effectively on hot days.

RavenBrick’s technology diagram (from the RavenBrick website)

Davies’ Treehugger article offers some figures regarding savings (and another illustration),

The RavenSkin Smart Wall System promises to cut energy bills by as much as 30 percent, so it’s sure to offset the costs of installation (not listed on the RavenBrick website). The “infrared power system” doesn’t involve electricity, moving parts or wires, so it’s low maintenance, [sic]

I would have liked a little more detail. How did they derive the savings number, i.e.,  “by as much as 30%”? Also, is there any data from the US Dept. of Energy? At any rate, this product is due to reach the marketplace sometime in 2013.

I last mentioned RavenBrick and their windows in my Aug. 5, 2009 posting. In my Sept. 7, 2011 posting about the US Dept. of Energy, I focussed on smart window research being done at their Lawrence Berkeley National Laboratory (Berkeley Lab).

Canadian scientists get more light in deal with the US Argonne National Laboratory

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Canada’s synchrotron, Canadian Light Source (based in Saskatchewan), has signed a new three-year deal with the US Dept. of Energy’s Argonne National Laboratory’s Advanced Photon Source (APS)  that will give Canadian scientists more access to the APS facilities, according to the June 18, 2012 news item at the  Nanowerk website,

Seeking to solve some of today’s greatest global problems, scientists using x-ray light source facilities at national research laboratories in the United States and Canada are sharing more expertise.

The Canadian Light Source (CLS) and the Advanced Photon Source (APS) at the U.S. Department of Energy’s (DOE’s) Argonne National Laboratory agreed in January 2012 to a Partner User Proposal that cements a stronger working relationship between the two facilities for the next three years. These two premier light sources use different but complementary x-ray techniques to probe materials in order to understand chemical and structural behavior.

Tone Kunz’s June 18, 2012 news release for the APS provides details about the deal,

This new agreement will provide Canadian scientists with more research time to use the x-ray light source facilities and more time on a larger number of APS beamlines. Using varied x-ray and imaging capabilities will broaden the range of experiments Canadians may undertake at the APS to augment their research done at the Canadian Light Source. X-ray science offers potential solutions to a broad range of problems in surface, material, environmental and earth sciences, condensed matter physics, chemistry, and geosciences.

Since the Sector 20 beamlines became fully operational, scientists from Canada and other areas who have used these beamlines at the APS have produced an average of 51 scientific publications a year. This research includes the study of more effective mineral exploration strategies, ways to mitigate mine waste and mercury contamination, and novel ways to fabricate nanomaterials for use in fuel cells, batteries, and LEDs.

I had not realized how longstanding the  CLS/APS relationship has been,

Before the Canadian Light Source began operation in 2004, a Canadian group led by Daryl Crozier of Simon Fraser University, working in partnership with colleagues at the University of Washington and the Pacific Northwest National Laboratory, helped found the Sector 20 beamlines at the APS as part of the Pacific Northwest Consortium Collaborative Access Team, or PNC-CAT. Parts of this team were included in the X-ray Science Division of the APS when it was formed.

This long-standing partnership has led to scientifically significant upgrades to the beamline. The new agreement will provide the valuable manpower and expertise to allow the APS to continue to push the innovation envelope. [emphasis mine]

As I was reading Kunz’s news release I kept asking, what’s in it for the APS? Apparently they need more “manpower and expertise.” Unfortunately, their future plans are a little shy of detail,

Scientists from the APS and the Canadian Light Source will work together on R&D projects to improve light-source technology. In particular, scientists will upgrade even further the two beamlines at Sector 20 in four key areas. This will provide a unique capability to prepare and measure in situ films and interfaces, a new technique to create quantitative three-dimensional chemical maps of samples, and improved forms of spectroscopy to expand the range of elements and types of environments that can be examined.

What are the four key areas? For that matter, what is Sector 20? I suspect some of my readers have similar questions about my postings. It’s easy (especially if you write frequently) to forget that your readers may not be as familiar as you are with the subject matter.

(I wrote about the CLS and another deal with a synchrotron in the UK in my May 31, 2011 posting.)

The quantum mechanics of photosynthesis

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Thankfully, Jared Sagoff included a description of photosynthesis (I’ve long since forgotten the mechanics of the process) in his May 21, 2012 article, Scientists uncover a photosynthetic puzzle, on the US Dept. of Energy’s Argonne National Laboratory website. From Sagoff’s article, here’s the photosynthesis  description along with a description of the quantum effect the scientists observed,

While different species of plants, algae and bacteria have evolved a variety of different mechanisms to harvest light energy, they all share a feature known as a photosynthetic reaction center. Pigments and proteins found in the reaction center help organisms perform the initial stage of energy conversion.

These pigment molecules, or chromophores, are responsible for absorbing the energy carried by incoming light. After a photon hits the cell, it excites one of the electrons inside the chromophore. As they observed the initial step of the process, Argonne scientists saw something no one had observed before: a single photon appeared to excite different chromophores simultaneously.

Here’s a gorgeous image of a leaf provided with the article,

I was aware that scientists are working at hard at duplicating photosynthesis but until reading this upcoming excerpt from Sagoff’s article, I had not appreciated the dimensions of the problem,

The result of the study could significantly influence efforts by chemists and nanoscientists to create artificial materials and devices that can imitate natural photosynthetic systems. Researchers still have a long way to go before they will be able to create devices that match the light harvesting efficiency of a plant.

One reason for this shortcoming, Tiede [Argonne biochemist David Tiede] explained, is that artificial photosynthesis experiments have not been able to replicate the molecular matrix that contains the chromophores. “The level that we are at with artificial photosynthesis is that we can make the pigments and stick them together, but we cannot duplicate any of the external environment,” he said.  “The next step is to build in this framework, and then these kinds of quantum effects may become more apparent.”

Because the moment when the quantum effect occurs is so short-lived – less than a trillionth of a second – scientists will have a hard time ascertaining biological and physical rationales for their existence in the first place. [emphasis mine] “It makes us wonder if they are really just there by accident, or if they are telling us something subtle and unique about these materials,” Tiede said. “Whatever the case, we’re getting at the fundamentals of the first step of energy conversion in photosynthesis.”

Thanks to Nanowerk for the May 24, 2012 news item which drew this article to my attention.

Thermal bottleneck opens up at US Dept.of Energy

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Heat is always an issue with electronics and as the devices get smaller and smaller, it becomes a more pressing problem. From the March 13, 2012 news item on Nanowerk,

For decades, engineers have sought to build more efficient electronic devices by reducing the size of their components. In the process of doing so, however, researchers have reached a “thermal bottleneck,” said Argonne [US Dept. of Energy, Argonne Laboratory] nanoscientist Anirudha Sumant.

In a thermal bottleneck, the excess heat generated in the device causes undesirable effects that affect its performance. “Unless we come-up with innovative ways to suck the heat off of our electronics, we are pretty much stuck with this bottleneck,” Sumant explained.

Diamond films have excited interest in the scientific community as a solution to thermal bottlenecks, from the news item,

The unusually attractive thermal properties of diamond thin films have led scientists to suggest using this material as a heat sink that could be integrated with a number of different semiconducting materials. However, the deposition temperatures for the diamond films typically exceed 800 degrees Celsius—roughly 1500 degrees Fahrenheit, which limits the feasibility of this approach.

Reducing the deposition temperature to 400 degrees Celsius would allow for integration of diamond materials with a whole range of semiconductor materials.  A new technique that allows just that thing has been developed (from the news item),

By using a new technique that altered the deposition process of the diamond films, Sumant and his colleagues at Argonne’s Center for Nanoscale Materials were able to both reduce the temperature to close to 400 degrees Celsius and to tune the thermal properties of the diamond films by controlling their grain size. This permitted the eventual combination of the diamond with two other important materials: graphene and gallium nitride.

According to Sumant, diamond has much better heat conduction properties than silicon or silicon oxide, which were traditionally used for fabrication of graphene devices. As a result of better heat removal, graphene devices fabricated on diamond can sustain much higher current densities.

In the other study, Sumant used the same technology to combine diamond thin films with gallium nitride, which is used extensively in high-power light emitting devices (LED). After depositing a 300 nm-thick diamond film on a gallium nitride substrate, Sumant and his colleagues noticed a considerable improvement in the thermal performance. Because a difference within an integrated circuit of just a few degrees can cause a noticeable change in performance, he called this result “remarkable.”

There are two published papers on the technique, one focusing on the graphene application and the other on the gallium nitride application. The first is in Nano Letters, 2012, 12 (3), pp 1603–1608, DOI: 10.1021/nl204545q, (“Graphene-on-Diamond Devices with Increased Current-Carrying Capacity: Carbon sp2-on-sp3Technology”, and the other is in Advanced Functional Materials, first published online: 1 FEB 2012, DOI: 10.1002/adfm.201102786,  (“Direct Low-Temperature Integration of Nanocrystalline Diamond with GaN Substrates for Improved Thermal Management of High-Power Electronics”).