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Hydrogen Fuel Cells for Automobiles Look More Feasible with Nanostructured Storage Material

I have been skeptical of claims that nanotechnology was going to help usher in the hydrogen economy. This skepticism is not without reason.

When it turned out that carbon nanotubes were in fact pretty poor at storing hydrogen and their storage capacity was closer to 1wt% in practicality than the lofty 50wt% storage that some research had claimed, I became somewhat jaded.

But there is a new, shiny knight that is challenging my cynicism. It’s a UK-based company called Cella Energy.

I came to know of them through their recent winning of the Shell Springboard Awards, which earns them £40,000 (approximately US$65,000) and a press release.

Now, while some have waxed poetic about hydrogen fuel cells powering cars of the future, others have whispered that the complete lack of any infrastructure for transporting and delivering hydrogen was a pretty steep obstacle, not to mention the extraordinary cost of isolating hydrogen.

But it is in the former barrier that Cella has offered a solution. It seems they have developed a way of trapping hydrides in a nanoporous polymer, or microbeads, which allows the hydrogen to be stored at low pressure and ambient temperatures.

Just to give you a sense of how difficult it has been to store hydrogen (and imagine this system strapped to your automobile), the pressure needed for storing hydrogen has been typically “700 times atmospheric pressure (700bar or 10,000psi) or super-cooled liquids at -253°C (-423°F).” That could be described as a ticking time bomb traveling with you underneath your car.

With the Cella system since there is no special cooling system required or pressurized storage cylinders the hydrogen storage packaging will look pretty much like a typical fuel tank found on cars today.

Cella has not made any dramatic claims about percentage of hydrogen storage capacity like the carbon nanotubes hullabaloo. At the moment, they say that their materials are performing at “6wt% weight percentage of hydrogen, but Cella is now working with complex hydrides that store hydrogen at up to 20wt%.” According to the company website, this exceeds “the revised 2009 Department of Energy targets to produce hydrogen storage materials that would compete with gasoline.”

This all sounds great, but perhaps what is most intriguing about this technology is that the microbeads can be added to conventional fuels in today’s engines and would lower the emissions of those vehicles “to meet the new EU Euro 6 standards for emissions with minor vehicle modifications.”

Apparently, the nanoporous polymer is cheap to produce and Cella claims to be ready to ramp up production, it has applications for both hydrogen fuels cells cars or if that never gets off the ground it makes a fine fuel additive for reducing emissions. So, what’s not to love?

I’m not really sure, but I am bit troubled by their remarks that £40,000 is going to tip them over the edge and now they can ramp up industrial scale production. I am sure they were just be grateful for the prize money, but if they are sincere I can’t see how that amount does much more than pay their staff a month’s salary.

Could Super Conducting Graphene Quantum Dots Lead to Solid-State Qubits?

Quantum computers are sometimes referred to as the Holy Grail of computing, or maybe the Philosopher’s Stone of computing might be another appropriate medieval reference to a nearly unattainable quest. In any case, while some outfits have claimed they have achieved fairly significant quantum computer prototypes despite being met with skepticism, creating a quantum computer that can calculate something beyond what a kid in elementary school can factor has proven difficult.

One of the fundamental issues researchers have faced in developing quantum computers has been the problem of getting the computers to maintain more than a few quantum bits (or qubits). One of the more promising ways of getting beyond a mere seven qubits has been the use of quantum dots.

Now researchers at the University of Illinois led by Nadya Mason have brought a new wrinkle into this field of research. The research, which was initially published in the journal Nature Physics, was looking at what happens when a normal conducting material like a metal or graphene is sandwiched between two superconducting materials and observing the interface of the materials.

While it has been observed previously that normal metals in these instances take on the characteristics of the superconductor material when current is passed through it (namely, that it too will pass electron pairs through it rather than a single stream of electrons), the Illinois researchers by working with graphene quantum dots were able to better understand the fundamental physics at play: Andreev bound states (ABS).

To date, ABS have proven to difficult to both measure and observe. At is at this point that the researchers developed a novel method to isolate individual ABS by connecting probes to quantum dots made from graphene. As quantum dots do they confined the confined ABS into discrete energy states, which permitted the researchers to not only measure the ABS but to manipulate them.

"Before this, it wasn't really possible to understand the fundamentals of what is transporting the current," Mason said. "Watching an individual bound state allows you to change one parameter and see how one mode changes. You can really get at a systematic understanding. It also allows you to manipulate ABS to use them for different things that just couldn't be done before."

The concurrence of the two nanomaterials, graphene and quantum dots, along with the superconducting material made the breakthrough possible. 

"This is a unique case where we found something that we couldn't have discovered without using all of these different elements – without the graphene, or the superconductor, or the quantum dot, it wouldn't have worked. All of these are really necessary to see this unusual state," Mason said.

The Blue Dye in the Ink of Your Pen Provides New Development in Both Spin and Molecular Electronics

In collaborative research between Karlsruhe Institue of Technology (KIT) Center for Functional Nanostructures (CFN) and the Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), scientists have developed what is being dubbed the ‘world’s smallest magnetic field sensor’ by using the organic molecule hydrogen-phtalocyanin, used as the blue dye in pens.

The research, which was initially published in the journal Nature Nanotechnology, has drawn together the fields of spin electronics (or, “spintronics”) and molecular electronics by using one organic molecule to generate giant magneto resistance (GMR). As the Nature article terms it, “Giant magnetoresistance through a single molecule.”

It looks as though it could have an immediate impact where the grand daddy of the spintronics revolution—GMR—already holds sway in read heads for hard disk drives but make the reading speed even faster and the data density even greater.

But according to Prof. Wulf Wulfhekel, the lead researcher on the project, in an interview he gave for an article on the research, hard disk drive sensors are just the beginning.

“The use of spin for information encoding has several advantages — it’s non-volatile so you don’t need power to save the state of your machine,” explains Wulfhekel. “If you switch off your computer and switch it back on again, you don’t need to boot up. And also the power consumption is far lower, so this has advantages for mobile devices especially.”

It’s not clear to me, however, whether the researchers see this merely as a breakthrough in the area of hard disk memory or they see it as a move towards some kind of transistor and logic circuit of the future. The article, in which Wulfhekel is quoted, brings up this issue by comparing the scales of this component (one nanometer in diameter) to a carbon nanotube-based transistor that is on the scale of tens of nanometers.

In any case, it seems researchers at KIT have been pursuing molecular electronics rigorously recently with work done “to form a rigid light-emitting device based on single molecules."

While the electro-luminescence research didn’t have a clear application area, this latest research in creating a GMR effect with one molecule seems to be targeting mobile devices.

More Proposals for Nanotechnology in Addressing Oil Spills

Last May when the news cycle was providing non-stop coverage of the Gulf of Mexico oil spill, I wondered how long it would take for someone to ask how nanotechnology could be applied to solve the problem.

The issue that I came to realize was not that there weren’t any interesting proposals for using nanotechnology to address oil spills, but that there weren’t any real commercial solutions that could be applied in that instance. The one commercial product that was available, a nanoparticle-based dispersant, seemed to generate more controversy than offer a remedy.

So now that we're in a new year, it seems that someone has sat down to do a thorough review of the possibilities of applying nanotechnology to oil spills, and it appears to be the work of an organization out of India called Centre for Knowledge Management of Nanoscience and Technology.

But as impressive a catalogue as it is, it still amounts only to possible solutions, which kind of misses the point of what I discovered is the problem. If you want to solve a problem, you have to set aside time, resources and focus one’s will to creating a solution, which no one has done. Making a list of possible solutions may help organize the process but somebody really has to roll up their sleeves and develop one of them. 

It might make sense if regulators required that if an oil company is going to engage in deep-sea drilling then they need to have the resources for containing and cleaning up possible oil spills. In such an instance, not only are we protected from huge environmental disasters but we also create a commercial need that may lead to new companies that can come up with nanotechnology-based solution.

Worm-like Nanoparticles Could Be Planted Under Our Skin for Glucose Monitoring

In collaborative work between researchers at MIT and Northeastern University in Boston, MA a comparatively long and hollow nanoparticle has been developed that could be implanted under the skin and remain anchored at its original location to monitor levels of glucose or salt or other targets over time.

The work, which was initially published online last month in the journal Proceedings of the National Academy of Sciences, builds on the work of Karen Gleason, one of the lead researchers on this project, in using chemical vapor deposition (CVD) to create a coating with microscopic pores.

The breakthrough of the new nanoparticle, which is being called “microworms”, has to do with their shape. While spherical nanoparticle have been developed that could be filled with specific chemicals to detect various biomedical conditions and then implanted under the skin, they just wouldn’t stay where they were. They would get washed away.

To combat this, the research team developed tubes that were narrow enough to keep them more or less on the same dimensions as the spherical nanoparticles but were long enough in length so that they would better anchor to the location at which they were originally implanted.

Where this particular research seems a bit odd to me is in the area of its proposed applications. Now I try to remember Eric Drexler’s point in his blog late last year that scientists are held to two different standards when discussing applications to fellow scientists and then to lay people, but I can’t imagine these applications would be particularly attractive to lay people.

To copy and paste a bit the application proposals they go something like ‘microworms’ would “someday lead to implantable devices that would allow, for example, people with diabetes to check their blood sugar just by glancing at an area of skin.”

Now I’ve known people that had to regularly check their glucose levels, and this amounted to a pin prick of their finger and a drop of blood on test strip, then into the meter and voila. Pretty quick and pretty painless. But do I really want some area under my skin to reveal my glucose level? Seems kind of a long way to go for a fairly diminished return.

New Microscopy Technique Could Reveal Mechanisms of Cancer

Typically when asked about the role of nanotechnology in treating cancer, people refer to nanoparticle-based drug delivery systems (DDS) that target cancer cells. While these DDS treatments certainly add a new weapon to the arsenal used in the killing of cancer cells, they are still, as George Whitesides has said, our cells. So, killing cancer cells with more targeted poisons remains somewhat problematic.

In some ways a more hopeful, albeit a less immediate, method of addressing cancer with nanotechnology, is the use of microscopy tools for both early detection and unraveling the mechanisms by which cancer develops in us.

It is in the latter case that Nongjian (N.J.) Tao and his fellow researchers at the Biodesign Institute at Arizona State University have developed a method for improving the spatial information to the microscopy technique known as electrochemical impedance spectroscopy (EIS).

The work that went into developing this technique was published in the journal Nature ChemistryIt seems the researchers have created a hybrid technique that combines EIS with a technique based on surface plasmon resonance (SPR).

The hybrid technique is being dubbed electrochemical impedance microscopy (EIM) and differs from traditional EIS in that it does not measure current but instead employs the plasmon resonance to show the changes in impedance optically.

This development means that it is now “possible to study individual cells, but also resolve subcellular structures and processes without labels, and with excellent detection sensitivity (~2 pS).”

What these characteristics of the new technique enable is made clear in the video below in which researchers at Arizona State University now have the tools they need to look at the chemical modifications of the proteins that wrap up DNA up to control gene expression.

“Lots of people have gene defects that could lead to cancer but few actually get cancer,” explains Dr. Stuart Lindsay, Director, Center for Single Molecule Biophysics, at the Biodesign Institute at ASU. “Cancer is not a disease based on gene defects per se, but rather based on the chemical factors that control gene expression and those are the factors that we want to probe.”

 

When a Two-Percent Solution Equals $22 million, Nanotechnology Matters

I have argued in the past that when it comes to nanotechnology and energy, it’s the mundane that’s interesting

Case in point, the UK-based airline EasyJet has just announced that they are embarking on a 12-month test of a new nanocoating that when applied to the exterior of their planes could reduce fuel consumption by as much as 2%.

 

When your annual fuel bill is £730m (nearly US$1.2 billion), then that 2% can mean a savings of £14m (approximately US$22.4 million). Suddenly a coating becomes interesting, doesn’t it?

Apparently the coating has been used on US military aircraft for some time but this will mark the first time the coating has been used on a commercial aircraft.

After coating an entire aircraft it only adds 4oz (113g) to the total weight of the plane, which, when compared to the 80kg (176 pounds) that regular paint adds to the weight of a plane, gives you an indication of how thin this nanocoating is.

The nanocoating basically fills in all the pits and crevices that exist within the paint on a microscopic scale, which ensures that no debris or dirt builds on the surface.

I don’t know who has developed the nanostructured coating but in the UK the company applying it the EasyJet aircraft is a company called TripleO. To get the coating to work, TripleO performs what they call a “polarizing wash” in which the surface of the aircraft is given a charge of positive polarity so when the polymer-based nanocoating is applied it will bond to the existing paint surface.

Initially, EasyJet is trying this out with eight planes, and if the cut in fuel costs are what they expecting then they will go ahead and coating the other rest of 200-plane fleet.

If this catches on with the entire commercial airline industry, then cuts in fuel consumption would be dramatic along with similar reductions in carbon emissions. You see, you don’t have to create a super efficient solar cell to make an impact in energy applications with nanotechnology.

For First Time Nanowires Create Programmable Logic

The typical refrain you hear when some introduces a new transistor design or material goes something like: “Let me know when you make a simple logic circuit.”

Okay, researchers at Harvard University, led by Charles Lieber, would like to let you know that they have used nanowires to create for the first time programmable logic “tiles”. The researchers dubbed the term “tiles” with the idea that each tile, which would have up to eight distinct logic gates, could be connected to other tiles to execute more complex logic functions.

An article here on the pages of Spectrum online has more on this breakthrough and the background research developments that led to it.

Just a personal note to this thorough article and the research, I have often gone back to an article penned by Professor Lieber back in 2007 for Scientific American entitled The Incredible Shrinking Circuit to inform my understanding of nanowire research, so I am always intrigued to see what he and his team are doing in this field.

While Lieber concedes that these nanowire-based logic tiles will not replace CMOS, since the transistors operate at comparatively slow speeds of only 10 to 100 megahertz, their high density and low power consumption could make them attractive for a “controller for some microelectromechanical device.”

Application possibilities are intriguing, but what is most appealing about this breakthrough to me is that it seems to be a major step in the process of leading us further down the road of the incredible shrinking circuit.

Risk and Opportunities of Nanotechnology

I have to confess to not always understanding the point of some forums or who the attended audience is supposed to be.

Such is the case for a webcast that ran live on Tuesday of this week (which has now been archived and you can access on the page I linked to here).

It has a distinguished panel, a noted moderator and a lively discussion for 50 minutes or so. But for what and for whom is this intended dare I ask?

It was put on by the University of Michigan Risk Research Center, which the moderator, Andrew Maynard, took the helm of late last year. And it has a clever title “Nanotechnology—Unplugged” that was somewhat unfortunate in that it left me wondering who thought that it was a good idea to plug it all into the Internet.

It’s not forming the basis of any regulatory framework, it’s not educating legislators or regulators as to the issues they face when tackling nanotechnology, it doesn’t present the kind of information that researchers, engineers and scientists might find beneficial to do their work and I think you could hardly call it a public engagement exercise—thank goodness for that.

So, the point of this webcast other than entertaining a handful of people eludes me. But alas, that’s not that important. Let’s take a look at the content.

We get a chemist who gives us the required definition of nanotech and its scale, we get a toxicologist who provides some science for looking at the risks of nanotechnology and a social scientist who is eager to have us take into account the instincts of the uninformed when approaching emerging technologies.

To me there were a few key exchanges. One that had my jaw drop and I already alluded to was when the social scientist said something to the effect: You don’t have to have an understanding of science to have instincts about a particular technology that are valuable in a few ways.

These ways amounted to market research for producers to avoid pitfalls and take advantage of unknown markets. Okay, but couldn’t I just ignore them and figure that out myself?

As the video below demonstrates, people’s instincts on science, especially when they are—shall we say—poorly informed, are really best avoided.

Then the toxicologist kind of made all the concern over nanotechnology, versus say just about any other toxic chemical that we use in our everyday lives, a little silly: There’s no connection yet between quantum mechanical properties of a material and toxicity.

Uh oh…somebody just spoiled the party. We were going to bring in Auntie Alice to ask about her instincts on the use of graphene versus molybdenite for gate materials, but it looks we might want to wait.

Nano-ink Research Gives New Life to Painted-on Solar Power Conversion

The perpetual balancing act between cost and efficiency that seems inherent in photovoltaics marches on.

We see this exhibited in among other things the “Photovoltaic Moore’s Law”, which is based on ever decreasing price points rather than the ever increasing number of transistors per unit of a chip—lowering price rather than heightening technology. But efficiencies still need to be improved for photovoltaics. So how do you improve the efficiency of a photovoltaic for turning sunlight into electricity when you’re overriding concern is to make the whole thing cheaper?

Recently, when it was argued that Multiexciton Generation, a process by which several charge carriers (electrons and holes) are generated from one photon, might not be as promising an avenue as had been hoped, the possibilities for thin film solar cells becoming more efficient took a fairly serious blow.

So, maybe the way to go is one that was presented to me in the comments to the blog entry cited at the top of this one: “When it comes to improving market penetration for solar power (which, after all, is what we are concerned with if we want to reduce fossil fuel use), you can't beat McDonalds for a business model. Make 'em cheap, make 'em fast, make 'em consistent, and have 'em ready when I'm hungry.”

Along these lines, researchers at the University of Texas have conducted research into using nanoparticle inks that would replace the standard solar cell manufacturing process. 

 

The research, which was originally published in the ACS journal The Journal of Physical Chemistry, could usher in that long-promised application of painting solar power onto a building.

However, at present spray-on nanoparticle inks for solar power are only 1% efficient. This will need to be improved, according to Brian Korgel, one of the researchers at the University of Texas.

“If we get to 10 percent, then there’s real potential for commercialization,” Korgel said. “If it works, I think you could see it being used in three to five years.”

It also appears that commercialization is at the forefront of the University of Texas’ plans as a partnership with Konarka Technologies was announced in January.

While three to five years may sound reasonable to a researcher who believes in their work, maybe the folks at Konarka can educate that researcher into the difficulties of getting a product to market no matter how promising the technology and the particularly difficult road for organic photovoltaics.

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Nanoclast

IEEE Spectrum’s nanotechnology blog, featuring news and analysis about the development, applications, and future of science and technology at the nanoscale.

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Dexter Johnson
Madrid, Spain
 
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