Tag Archives: electricity

Tracks of my tears could power smartphone?

So far the researchers aren’t trying to power anything with tears but they have discovered that tears could be used to generate electricity (from an Oct. 2, 2017 news item on phys.org),

A team of Irish scientists has discovered that applying pressure to a protein found in egg whites and tears can generate electricity. The researchers from the Bernal Institute, University of Limerick (UL), Ireland, observed that crystals of lysozyme, a model protein that is abundant in egg whites of birds as well as in the tears, saliva and milk of mammals can generate electricity when pressed. Their report is published today (October 2) in the journal, Applied Physics Letters.

An Oct. 2, 2017 University of Limerick press release (also on EurekAlert), which originated the news item, offers additional detail,

The ability to generate electricity by applying pressure, known as direct piezoelectricity, is a property of materials such as quartz that can convert mechanical energy into electrical energy and vice versa. Such materials are used in a variety of applications ranging from resonators and vibrators in mobile phones to deep ocean sonars and ultrasound imaging. Bone, tendon and wood are long known to possess piezoelectricity.

“While piezoelectricity is used all around us, the capacity to generate electricity from this particular protein had not been explored. The extent of the piezoelectricity in lysozyme crystals is significant. It is of the same order of magnitude found in quartz. However, because it is a biological material, it is non toxic so it could have many innovative applications such as electroactive anti-microbial coatings for medical implants,” explained Aimee Stapleton, the lead author and an Irish Research Council EMBARK Postgraduate Fellow in the Department of Physics and Bernal Institute of UL.

Crystals of lysozyme are easy to make from natural sources. “The high precision structure of lysozyme crystals has been known since 1965,” said structural biologist at UL and co-author Professor Tewfik Soulimane.
“In fact, it is the second protein structure and the first enzyme structure that was ever solved,” he added, “but we are the first to use these crystals to show the evidence of piezoelectricity”.

According to team leader Professor Tofail Syed of UL’s Department of Physics, “Crystals are the gold-standard for measuring piezoelectricity in non-biological materials. Our team has shown that the same approach can be taken in understanding this effect in biology. This is a new approach as scientists so far have tried to understand piezoelectricity in biology using complex hierarchical structures such as tissues, cells or polypeptides rather than investigating simpler fundamental building blocks”.

The discovery may have wide reaching applications and could lead to further research in the area of energy harvesting and flexible electronics for biomedical devices. Future applications of the discovery may include controlling the release of drugs in the body by using lysozyme as a physiologically mediated pump that scavenges energy from its surroundings. Being naturally biocompatible and piezoelectric, lysozyme may present an alternative to conventional piezoelectric energy harvesters, many of which contain toxic elements such as lead.

Professor Luuk van der Wielen, Director of Bernal Institute and Bernal Professor of Biosystems Engineering and Design expressed his delight at this breakthrough by UL scientists.

“The €109-million Bernal Institute has the ambition to impact the world on the basis of top science in an increasingly international context. The impact of this discovery in the field of biological piezoelectricity will be huge and Bernal scientists are leading from the front the progress in this field,” he said.

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

The direct piezoelectric effect in the globular protein lysozyme featured by A. Stapleton, M. R. Noor, J. Sweeney, V. Casey, A. L. Kholkin, C. Silien, A. A. Gandhi, T. Soulimane, and S. A. M. Tofail. Appl. Phys. Lett. 111, 142902 (2017); doi: http://dx.doi.org/10.1063/1.4997446

This paper is open access.

As for Tracks of My Tears,

Vampire nanogenerators: 2017

Researchers have been working on ways to harvest energy from bloodstreams. I last wrote about this type of research in an April 3, 2009 posting about ‘vampire batteries ‘(for use in pacemakers). The latest work according to a Sept. 8, 2017 news item on Nanowerk comes from China,

Men build dams and huge turbines to turn the energy of waterfalls and tides into electricity. To produce hydropower on a much smaller scale, Chinese scientists have now developed a lightweight power generator based on carbon nanotube fibers suitable to convert even the energy of flowing blood in blood vessels into electricity. They describe their innovation in the journal Angewandte Chemie (“A One-Dimensional Fluidic Nanogenerator with a High Power Conversion Efficiency”)

A Sept. 8, 2017 Wiley Publishing news release (also on EurekAlert), which originated the news item, expands on the theme,

For thousands of years, people have used the energy of flowing or falling water for their purposes, first to power mechanical engines such as watermills, then to generate electricity by exploiting height differences in the landscape or sea tides. Using naturally flowing water as a sustainable power source has the advantage that there are (almost) no dependencies on weather or daylight. Even flexible, minute power generators that make use of the flow of biological fluids are conceivable. How such a system could work is explained by a research team from Fudan University in Shanghai, China. Huisheng Peng and his co-workers have developed a fiber with a thickness of less than a millimeter that generates electrical power when surrounded by flowing saline solution—in a thin tube or even in a blood vessel.

The construction principle of the fiber is quite simple. An ordered array of carbon nanotubes was continuously wrapped around a polymeric core. Carbon nanotubes are well known to be electroactive and mechanically stable; they can be spun and aligned in sheets. In the as-prepared electroactive threads, the carbon nanotube sheets coated the fiber core with a thickness of less than half a micron. For power generation, the thread or “fiber-shaped fluidic nanogenerator” (FFNG), as the authors call it, was connected to electrodes and immersed into flowing water or simply repeatedly dipped into a saline solution. “The electricity was derived from the relative movement between the FFNG and the solution,” the scientists explained. According to the theory, an electrical double layer is created around the fiber, and then the flowing solution distorts the symmetrical charge distribution, generating an electricity gradient along the long axis.

The power output efficiency of this system was high. Compared with other types of miniature energy-harvesting devices, the FFNG was reported to show a superior power conversion efficiency of more than 20%. Other advantages are elasticity, tunability, lightweight, and one-dimensionality, thus offering prospects of exciting technological applications. The FFNG can be made stretchable just by spinning the sheets around an elastic fiber substrate. If woven into fabrics, wearable electronics become thus a very interesting option for FFNG application. Another exciting application is the harvesting of electrical energy from the bloodstream for medical applications. First tests with frog nerves proved to be successful.

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

A One-Dimensional Fluidic Nanogenerator with a High Power Conversion Efficiency by Yifan Xu, Dr. Peining Chen, Jing Zhang, Songlin Xie, Dr. Fang Wan, Jue Deng, Dr. Xunliang Cheng, Yajie Hu, Meng Liao, Dr. Bingjie Wang, Dr. Xuemei Sun, and Prof. Dr. Huisheng Peng. Angewandte Chemie International Edition DOI: 10.1002/anie.201706620 Version of Record online: 7 SEP 2017

© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

This paper is behind a paywall.

Yarns that harvest and generate energy

The researchers involved in this work are confident enough about their prospects that they will be  patenting their research into yarns. From an August 25, 2017 news item on Nanowerk,

An international research team led by scientists at The University of Texas at Dallas and Hanyang University in South Korea has developed high-tech yarns that generate electricity when they are stretched or twisted.

In a study published in the Aug. 25 [2017] issue of the journal Science (“Harvesting electrical energy from carbon nanotube yarn twist”), researchers describe “twistron” yarns and their possible applications, such as harvesting energy from the motion of ocean waves or from temperature fluctuations. When sewn into a shirt, these yarns served as a self-powered breathing monitor.

“The easiest way to think of twistron harvesters is, you have a piece of yarn, you stretch it, and out comes electricity,” said Dr. Carter Haines, associate research professor in the Alan G. MacDiarmid NanoTech Institute at UT Dallas and co-lead author of the article. The article also includes researchers from South Korea, Virginia Tech, Wright-Patterson Air Force Base and China.

An August 25, 2017 University of Texas at Dallas news release, which originated the news item, expands on the theme,

Yarns Based on Nanotechnology

The yarns are constructed from carbon nanotubes, which are hollow cylinders of carbon 10,000 times smaller in diameter than a human hair. The researchers first twist-spun the nanotubes into high-strength, lightweight yarns. To make the yarns highly elastic, they introduced so much twist that the yarns coiled like an over-twisted rubber band.

In order to generate electricity, the yarns must be either submerged in or coated with an ionically conducting material, or electrolyte, which can be as simple as a mixture of ordinary table salt and water.

“Fundamentally, these yarns are supercapacitors,” said Dr. Na Li, a research scientist at the NanoTech Institute and co-lead author of the study. “In a normal capacitor, you use energy — like from a battery — to add charges to the capacitor. But in our case, when you insert the carbon nanotube yarn into an electrolyte bath, the yarns are charged by the electrolyte itself. No external battery, or voltage, is needed.”

When a harvester yarn is twisted or stretched, the volume of the carbon nanotube yarn decreases, bringing the electric charges on the yarn closer together and increasing their energy, Haines said. This increases the voltage associated with the charge stored in the yarn, enabling the harvesting of electricity.

Stretching the coiled twistron yarns 30 times a second generated 250 watts per kilogram of peak electrical power when normalized to the harvester’s weight, said Dr. Ray Baughman, director of the NanoTech Institute and a corresponding author of the study.

“Although numerous alternative harvesters have been investigated for many decades, no other reported harvester provides such high electrical power or energy output per cycle as ours for stretching rates between a few cycles per second and 600 cycles per second.”

Lab Tests Show Potential Applications

In the lab, the researchers showed that a twistron yarn weighing less than a housefly could power a small LED, which lit up each time the yarn was stretched.

To show that twistrons can harvest waste thermal energy from the environment, Li connected a twistron yarn to a polymer artificial muscle that contracts and expands when heated and cooled. The twistron harvester converted the mechanical energy generated by the polymer muscle to electrical energy.

“There is a lot of interest in using waste energy to power the Internet of Things, such as arrays of distributed sensors,” Li said. “Twistron technology might be exploited for such applications where changing batteries is impractical.”

The researchers also sewed twistron harvesters into a shirt. Normal breathing stretched the yarn and generated an electrical signal, demonstrating its potential as a self-powered respiration sensor.

“Electronic textiles are of major commercial interest, but how are you going to power them?” Baughman said. “Harvesting electrical energy from human motion is one strategy for eliminating the need for batteries. Our yarns produced over a hundred times higher electrical power per weight when stretched compared to other weavable fibers reported in the literature.”

Electricity from Ocean Waves

“In the lab we showed that our energy harvesters worked using a solution of table salt as the electrolyte,” said Baughman, who holds the Robert A. Welch Distinguished Chair in Chemistry in the School of Natural Sciences and Mathematics. “But we wanted to show that they would also work in ocean water, which is chemically more complex.”

In a proof-of-concept demonstration, co-lead author Dr. Shi Hyeong Kim, a postdoctoral researcher at the NanoTech Institute, waded into the frigid surf off the east coast of South Korea to deploy a coiled twistron in the sea. He attached a 10 centimeter-long yarn, weighing only 1 milligram (about the weight of a mosquito), between a balloon and a sinker that rested on the seabed.

Every time an ocean wave arrived, the balloon would rise, stretching the yarn up to 25 percent, thereby generating measured electricity.

Even though the investigators used very small amounts of twistron yarn in the current study, they have shown that harvester performance is scalable, both by increasing twistron diameter and by operating many yarns in parallel.

“If our twistron harvesters could be made less expensively, they might ultimately be able to harvest the enormous amount of energy available from ocean waves,” Baughman said. “However, at present these harvesters are most suitable for powering sensors and sensor communications. Based on demonstrated average power output, just 31 milligrams of carbon nanotube yarn harvester could provide the electrical energy needed to transmit a 2-kilobyte packet of data over a 100-meter radius every 10 seconds for the Internet of Things.”

Researchers from the UT Dallas Erik Jonsson School of Engineering and Computer Science and Lintec of America’s Nano-Science & Technology Center also participated in the study.

The investigators have filed a patent on the technology.

In the U.S., the research was funded by the Air Force, the Air Force Office of Scientific Research, NASA, the Office of Naval Research and the Robert A. Welch Foundation. In Korea, the research was supported by the Korea-U.S. Air Force Cooperation Program and the Creative Research Initiative Center for Self-powered Actuation of the National Research Foundation and the Ministry of Science.

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

Harvesting electrical energy from carbon nanotube yarn twist by Shi Hyeong Kim, Carter S. Haines, Na Li, Keon Jung Kim, Tae Jin Mun, Changsoon Choi, Jiangtao Di, Young Jun Oh, Juan Pablo Oviedo, Julia Bykova, Shaoli Fang, Nan Jiang, Zunfeng Liu, Run Wang, Prashant Kumar, Rui Qiao, Shashank Priya, Kyeongjae Cho, Moon Kim, Matthew Steven Lucas, Lawrence F. Drummy, Benji Maruyama, Dong Youn Lee, Xavier Lepró, Enlai Gao, Dawood Albarq, Raquel Ovalle-Robles, Seon Jeong Kim, Ray H. Baughman. Science 25 Aug 2017: Vol. 357, Issue 6353, pp. 773-778 DOI: 10.1126/science.aam8771

This paper is behind a paywall.

Dexter Johnson in an Aug. 25, 2017 posting on his Nanoclast blog (on the IEEE [Institute of Electrical and Electronics Engineers] website) delves further into the research,

“Basically what’s happening is when we stretch the yarn, we’re getting a change in capacitance of the yarn. It’s that change that allows us to get energy out,” explains Carter Haines, associate research professor at UT Dallas and co-lead author of the paper describing the research, in an interview with IEEE Spectrum.

This makes it similar in many ways to other types of energy harvesters. For instance, in other research, it has been demonstrated—with sheets of rubber with coated electrodes on both sides—that you can increase the capacitance of a material when you stretch it and it becomes thinner. As a result, if you have charge on that capacitor, you can change the voltage associated with that charge.

“We’re more or less exploiting the same effect but what we’re doing differently is we’re using an electric chemical cell to do this,” says Haines. “So we’re not changing double layer capacitance in normal parallel plate capacitors. But we’re actually changing the electric chemical capacitance on the surface of a super capacitor yarn.”

While there are other capacitance-based energy harvesters, those other devices require extremely high voltages to work because they’re using parallel plate capacitors, according to Haines.

Dexter asks good questions and his post is very informative.

“Innovation and its enemies” and “Science in Wonderland”: a commentary on two books and a few thoughts about fish (1 of 2)

There’s more than one way to approach the introduction of emerging technologies and sciences to ‘the public’. Calestous Juma in his 2016 book, ”Innovation and Its Enemies; Why People Resist New Technologies” takes a direct approach, as can be seen from the title while Melanie Keene’s 2015 book, “Science in Wonderland; The Scientific Fairy Tales of Victorian Britain” presents a more fantastical one. The fish in the headline tie together, thematically and tenuously, both books with a real life situation.

Innovation and Its Enemies

Calestous Juma, the author of “Innovation and Its Enemies” has impressive credentials,

  • Professor of the Practice of International Development,
  • Director of the Science, Technology, and Globalization Project at Harvard Kennedy School’s Better Science and International Affairs,
  • Founding Director of the African Centre for Technology Studies in Nairobi (Kenya),
  • Fellow of the Royal Society of London, and
  • Foreign Associate of the US National Academy of Sciences.

Even better, Juma is an excellent storyteller perhaps too much so for a book which presents a series of science and technology adoption case histories. (Given the range of historical time periods, geography, and the innovations themselves, he always has to stop short.)  The breadth is breathtaking and Juma manages with aplomb. For example, the innovations covered include: coffee, electricity, mechanical refrigeration, margarine, recorded sound, farm mechanization, and the printing press. He also covers two recently emerging technologies/innovations: transgenic crops and AquAdvantage salmon (more about the salmon later).

Juma provides an analysis of the various ways in which the public and institutions panic over innovation and goes on to offer solutions. He also injects a subtle note of humour from time to time. Here’s how Juma describes various countries’ response to risks and benefits,

In the United States products are safe until proven risky.

In France products are risky until proven safe.

In the United Kingdom products are risky even when proven safe.

In India products are safe when proven risky.

In Canada products are neither safe nor risky.

In Japan products are either safe or risky.

In Brazil products are both safe and risky.

In sub-Saharan Africa products are risky even if they do not exist. (pp. 4-5)

To Calestous Juma, thank you for mentioning Canada and for so aptly describing the quintessentially Canadian approach to not just products and innovation but to life itself, ‘we just don’t know; it could be this or it could be that or it could be something entirely different; we just don’t know and probably will never know.’.

One of the aspects that I most appreciated in this book was the broadening of the geographical perspective on innovation and emerging technologies to include the Middle East, China, and other regions/countries. As I’ve  noted in past postings, much of the discussion here in Canada is Eurocentric and/or UScentric. For example, the Council of Canadian Academies which conducts assessments of various science questions at the request of Canadian and regional governments routinely fills the ‘international’ slot(s) for their expert panels with academics from Europe (mostly Great Britain) and/or the US (or sometimes from Australia and/or New Zealand).

A good example of Juma’s expanded perspective on emerging technology is offered in Art Carden’s July 7, 2017 book review for Forbes.com (Note: A link has been removed),

In the chapter on coffee, Juma discusses how Middle Eastern and European societies resisted the beverage and, in particular, worked to shut down coffeehouses. Islamic jurists debated whether the kick from coffee is the same as intoxication and therefore something to be prohibited. Appealing to “the principle of original permissibility — al-ibaha, al-asliya — under which products were considered acceptable until expressly outlawed,” the fifteenth-century jurist Muhamad al-Dhabani issued several fatwas in support of keeping coffee legal.

This wasn’t the last word on coffee, which was banned and permitted and banned and permitted and banned and permitted in various places over time. Some rulers were skeptical of coffee because it was brewed and consumed in public coffeehouses — places where people could indulge in vices like gambling and tobacco use or perhaps exchange unorthodox ideas that were a threat to their power. It seems absurd in retrospect, but political control of all things coffee is no laughing matter.

The bans extended to Europe, where coffee threatened beverages like tea, wine, and beer. Predictably, and all in the name of public safety (of course!), European governments with the counsel of experts like brewers, vintners, and the British East India Tea Company regulated coffee importation and consumption. The list of affected interest groups is long, as is the list of meddlesome governments. Charles II of England would issue A Proclamation for the Suppression of Coffee Houses in 1675. Sweden prohibited coffee imports on five separate occasions between 1756 and 1817. In the late seventeenth century, France required that all coffee be imported through Marseilles so that it could be more easily monopolized and taxed.

Carden who teaches economics at Stanford University (California, US) focuses on issues of individual liberty and the rule of law with regards to innovation. I can appreciate the need to focus tightly when you have a limited word count but Carden could have a spared a few words to do more justice to Juma’s comprehensive and focused work.

At the risk of being accused of the fault I’ve attributed to Carden, I must mention the printing press chapter. While it was good to see a history of the printing press and attendant social upheavals noting its impact and discovery in regions other than Europe; it was shocking to someone educated in Canada to find Marshall McLuhan entirely ignored. Even now, I believe it’s virtually impossible to discuss the printing press as a technology, in Canada anyway, without mentioning our ‘communications god’ Marshall McLuhan and his 1962 book, The Gutenberg Galaxy.

Getting back to Juma’s book, his breadth and depth of knowledge, history, and geography is packaged in a relatively succinct 316 pp. As a writer, I admire his ability to distill the salient points and to devote chapters on two emerging technologies. It’s notoriously difficult to write about a currently emerging technology and Juma even managed to include a reference published only months (in early 2016) before “Innovation and its enemires” was published in July 2016.

Irrespective of Marshall McLuhan, I feel there are a few flaws. The book is intended for policy makers and industry (lobbyists, anyone?), he reaffirms (in academia, industry, government) a tendency toward a top-down approach to eliminating resistance. From Juma’s perspective, there needs to be better science education because no one who is properly informed should have any objections to an emerging/new technology. Juma never considers the possibility that resistance to a new technology might be a reasonable response. As well, while there was some mention of corporate resistance to new technologies which might threaten profits and revenue, Juma didn’t spare any comments about how corporate sovereignty and/or intellectual property issues are used to stifle innovation and quite successfully, by the way.

My concerns aside, testimony to the book’s worth is Carden’s review almost a year after publication. As well, Sir Peter Gluckman, Chief Science Advisor to the federal government of New Zealand, mentions Juma’s book in his January 16, 2017 talk, Science Advice in a Troubled World, for the Canadian Science Policy Centre.

Science in Wonderland

Melanie Keene’s 2015 book, “Science in Wonderland; The scientific fairy tales of Victorian Britain” provides an overview of the fashion for writing and reading scientific and mathematical fairy tales and, inadvertently, provides an overview of a public education programme,

A fairy queen (Victoria) sat on the throne of Victoria’s Britain, and she presided over a fairy tale age. The nineteenth century witnessed an unprecedented interest in fairies and in their tales, as they were used as an enchanted mirror in which to reflection question, and distort contemporary society.30  …  Fairies could be found disporting themselves thought the century on stage and page, in picture and print, from local haunts to global transports. There were myriad ways in which authors, painters, illustrators, advertisers, pantomime performers, singers, and more, capture this contemporary enthusiasm and engaged with fairyland and folklore; books, exhibitions, and images for children were one of the most significant. (p. 13)

… Anthropologists even made fairies the subject of scientific analysis, as ‘fairyology’ determined whether fairies should be part of natural history or part of supernatural lore; just on aspect of the revival of interest in folklore. Was there a tribe of fairy creatures somewhere out thee waiting to be discovered, across the globe of in the fossil record? Were fairies some kind of folks memory of any extinct race? (p. 14)

Scientific engagements with fairyland was widespread, and not just as an attractive means of packaging new facts for Victorian children.42 … The fairy tales of science had an important role to play in conceiving of new scientific disciplines; in celebrating new discoveries; in criticizing lofty ambitions; in inculcating habits of mind and body; in inspiring wonder; in positing future directions; and in the consideration of what the sciences were, and should be. A close reading of these tales provides a more sophisticated understanding of the content and status of the Victorian sciences; they give insights into what these new scientific disciplines were trying to do; how they were trying to cement a certain place in the world; and how they hoped to recruit and train new participants. (p. 18)

Segue: Should you be inclined to believe that society has moved on from fairies; it is possible to become a certified fairyologist (check out the fairyologist.com website).

“Science in Wonderland,” the title being a reference to Lewis Carroll’s Alice, was marketed quite differently than “innovation and its enemies”. There is no description of the author, as is the protocol in academic tomes, so here’s more from her webpage on the University of Cambridge (Homerton College) website,

Fellow, Graduate Tutor, Director of Studies for History and Philosophy of Science

Getting back to Keene’s book, she makes the point that the fairy tales were based on science and integrated scientific terminology in imaginative ways although some books with more success than other others. Topics ranged from paleontology, botany, and astronomy to microscopy and more.

This book provides a contrast to Juma’s direct focus on policy makers with its overview of the fairy narratives. Keene is primarily interested in children but her book casts a wider net  “… they give insights into what these new scientific disciplines were trying to do; how they were trying to cement a certain place in the world; and how they hoped to recruit and train new participants.”

In a sense both authors are describing how technologies are introduced and integrated into society. Keene provides a view that must seem almost halcyon for many contemporary innovation enthusiasts. As her topic area is children’s literature any resistance she notes is primarily literary invoking a debate about whether or not science was killing imagination and whimsy.

It would probably help if you’d taken a course in children’s literature of the 19th century before reading Keene’s book is written . Even if you haven’t taken a course, it’s still quite accessible, although I was left wondering about ‘Alice in Wonderland’ and its relationship to mathematics (see Melanie Bayley’s December 16, 2009 story for the New Scientist for a detailed rundown).

As an added bonus, fairy tale illustrations are included throughout the book along with a section of higher quality reproductions.

One of the unexpected delights of Keene’s book was the section on L. Frank Baum and his electricity fairy tale, “The Master Key.” She stretches to include “The Wizard of Oz,” which doesn’t really fit but I can’t see how she could avoid mentioning Baum’s most famous creation. There’s also a surprising (to me) focus on water, which when it’s paired with the interest in microscopy makes sense. Keene isn’t the only one who has to stretch to make things fit into her narrative and so from water I move onto fish bringing me back to one of Juma’s emerging technologies

Part 2: Fish and final comments

New electrical contact technology to exploit nanoscale catalytic effects

A Jan. 20,, 2017 news item on Nanotechnology Now announces research into nanoscale electrical contact technology,

Research by scientists at Swansea University [UK] is helping to meet the challenge of incorporating nanoscale structures into future semiconductor devices that will create new technologies and impact on all aspects of everyday life.

Dr Alex Lord and Professor Steve Wilks from the Centre for Nanohealth led the collaborative research published in Nano Letters. The research team looked at ways to engineer electrical contact technology on minute scales with simple and effective modifications to nanowires that can be used to develop enhanced devices based on the nanomaterials. Well-defined electrical contacts are essential for any electrical circuit and electronic device because they control the flow of electricity that is fundamental to the operational capability.

Everyday materials that are being scaled down to the size of nanometres (one million times smaller than a millimetre on a standard ruler) by scientists on a global scale are seen as the future of electronic devices. The scientific and engineering advances are leading to new technologies such as energy producing clothing to power our personal gadgets and sensors to monitor our health and the surrounding environment.

Over the coming years this will make a massive contribution to the explosion that is the Internet of Things connecting everything from our homes to our cars into a web of communication. All of these new technologies require similar advances in electrical circuits and especially electrical contacts that allow the devices to work correctly with electricity.

A Jan. 19, 2017 Swansea University press release (also on EurekAlert), which originated the news item, explains in greater detail,

Professor Steve Wilks said: “Nanotechnology has delivered new materials and new technologies and the applications of nanotechnology will continue to expand over the coming decades with much of its usefulness stemming from effects that occur at the atomic- or nano-scale. With the advent of nanotechnology, new technologies have emerged such as chemical and biological sensors, quantum computing, energy harvesting, lasers, and environmental and photon-detectors, but there is a pressing need to develop new electrical contact preparation techniques to ensure these devices become an everyday reality.”

“Traditional methods of engineering electrical contacts have been applied to nanomaterials but often neglect the nanoscale effects that nanoscientists have worked so hard to uncover.  Currently, there isn’t a design toolbox to make electrical contacts of chosen properties to nanomaterials and in some respects the research is lagging behind our potential application of the enhanced materials.”

The Swansea research team1 used specialist experimental equipment and collaborated with Professor Quentin Ramasse of the SuperSTEM Laboratory, Science and Facilities Technology Council.  The scientists were able to physically interact with the nanostructures and measure how the nanoscale modifications affected the electrical performance.

Their experiments found for the first time, that simple changes to the catalyst edge can turn-on or turn-off the dominant electrical conduction and most importantly reveal a powerful technique that will allow nanoengineers to select the properties of manufacturable nanowire devices.

Dr Lord said: “The experiments had a simple premise but were challenging to optimise and allow atomic-scale imaging of the interfaces. However, it was essential to this study and will allow many more materials to be investigated in a similar way.”

“This research now gives us an understanding of these new effects and will allow engineers in the future to reliably produce electrical contacts to these nanomaterials which is essential for the materials to be used in the technologies of tomorrow.

“In the near future this work can help enhance current nanotechnology devices such as biosensors and also lead to new technologies such as Transient Electronics that are devices that diminish and vanish without a trace which is an essential property when they are applied as diagnostic tools inside the human body.”

1. Lord, A. M., Ramasse, Q. M., Kepaptsoglou, D. M., Evans, J. E., Davies, P. R., Ward, M. B. & Wilks, S. P. 2016 Modifying the Interface Edge to Control the Electrical Transport Properties of Nanocontacts to Nanowires. Nano Lett. (doi:10.1021/acs.nanolett.6b03699). http://pubs.acs.org/doi/abs/10.1021/acs.nanolett.6b03699
2 .Lord, A. M. et al. 2015 Controlling the electrical transport properties of nanocontacts to nanowires. Nano Lett. 15, 4248–4254. (doi:10.1021/nl503743t) http://pubs.acs.org/doi/abs/10.1021/nl503743t

Both papers are open access.

Environmentally sustainable electromobility

Researchers at the Norwegian University of Science and Technology pose an interesting question in a Dec. 8, 2016 news item on Nanowerk,

Does it really help to drive an electric car if the electricity you use to charge the batteries come from a coal mine in Germany, or if the batteries were manufactured in China using coal?

Researchers at the Norwegian University of Science and Technology’s Industrial Ecology Programme have looked at all of the environmental costs of electric vehicles to determine the cradle-to-grave environmental footprint of building and operating these vehicles.

Increasingly, researchers are examining not just immediate environmental impacts but the impact a product has throughout its life cycle as this Dec. 8, 2016 Norwegian University of Science and Technology press release on EurekAlert notes,

In the 6 December [2016] issue of Nature Nanotechnology, the researchers report on a model that can help guide developers as they consider new nanomaterials for batteries or fuel cells. The goal is to create the most environmentally sustainable vehicle fleet possible, which is no small challenge given that there are already an estimated 1 billion cars and light trucks on the world’s roads, a number that is expected to double by 2035.

With this in mind, the researchers created an environmental life-cycle screening framework that looked at the environmental and other impacts of extraction, refining, synthesis, performance, durability and recyclablility of materials.

This allowed the researchers to evaluate the most promising nanomaterials for lithium-ion batteries (LIB) and proton exchange membrane hydrogen fuel cells (PEMFC) as power sources for electric vehicles. “Our analysis of the current situation clearly outlines the challenge,” the researchers wrote. “The materials with the best potential environmental profiles during the material extraction and production phase…. often present environmental disadvantages during their use phase… and vice versa.”

The hope is that by identifying all the environmental costs of different materials used to build electric cars, designers and engineers can “make the right design trade-offs that optimize LIB and PEMFC nanomaterials for EV usage towards mitigating climate change,” the authors wrote.

They encouraged material scientists and those who conduct life-cycle assessments to work together so that electric cars can be a key contributor to mitigating the effects of transportation on climate change.

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

Nanotechnology for environmentally sustainable electromobility by Linda Ager-Wick Ellingsen, Christine Roxanne Hung, Guillaume Majeau-Bettez, Bhawna Singh, Zhongwei Chen, M. Stanley Whittingham, & Anders Hammer Strømman. Nature Nanotechnology 11, 1039–1051 (2016)  doi:10.1038/nnano.2016.237 Published online 06 December 2016 Corrected online 14 December 2016

This paper is behind a paywall.

Monster science (a book announcement and interview)

Helaine Becker has launched a new children’s science book incorporating monsters with science. The title, unsurprisingly, is: ‘Monster Science’. Here’s more about the book from Helaine’s Oct. 14, 2016 post on Sci/Why where she shares two reviews,

“From Frankenstein’s creation to Nessie, Becker uses the creatures of our scariest stories as a springboard for an introduction to the scientific understandings that might make such creatures possible—or impossible. In addition to man-made monsters and legendary sea creatures, she covers vampires, zombies, werewolves, and wild, humanlike creatures like Bigfoot. Chapter by chapter, she provides references from literature, film, and popular culture, including a bit of science, a bit of history, and a plentiful helping of humor. She includes numerous monster facts, suggests weapons of defense, and concludes each section with a test-yourself quiz. Science topics covered range widely: electricity, genetic engineering, “demonic diseases,” the nature of our blood and the circulatory system, the possibility of immortality, animal classification, evolution, cannibalism, optical illusions, heredity, hoaxes, and the very real profession of cryptozoology, or the search for hitherto unidentified creatures. … Kirkus

Then, there’s this one,

A highlight of this work is its exploration of the often symbiotic relationship between culture and science; figures such as Shelley, John Polidori (The Vampyre), and filmmaker George Romero (Night of the Living Dead) merged cultural fascination with scientific development to create truly inspiring works and further public interest in science… School Library Journal

Interview with Helaine Becker

Not to be confused with ‘Interview with a vampire’, this one is not novel-length and includes a scoop about an upcoming book in 2017,

Were you surprised by anything when you were researching and/or witting the book?

I learned so much while writing Monster Science – it’s one of the reasons I enjoy writing nonfiction, especially for kids. I always turn up fascinating stuff. I was surprised to learn that werewolves were rounded up and burned at the stake, just like witches, during the period of the Inquisition. Werewolves, it turns out, were thought to be witches – usually male ones – who could shape shift.

My fave fact of all is that vampires would still have to eat their vegetables.

Did you have to leave any monsters/pop culture references/science out of the book? And, why?

Children’s books have very tight space constraints, but my research is comprehensive and complete. That means we have to pick and choose what stays in. It’s gotta be the very best! I work closely with my editors on this, and sometimes we have, shall we say, “heated” discussions.” For Monster Science, I was particularly sorry to see the fascinating back story of the mad scientist trope end up with a stake in its heart.

Did you have a favourite monster before you started? If so, has your favourite changed? Or if you didn’t have one before writing the book, have you since developed a favourite monster?

I’ve had an uneasy relationship with vampires from the age of about 7, after watching an episode of Gilligan’s Island. It featured a “humorous” dream sequence with Gilligan as the vampire. I failed to see the humor at that tender age, and was terrified out of my socks. And anyone remember the original Dark Shadows? Barnabus Collins? Yeah. That show should have never been on in the afternoon. I slept with the blankies up to my ears until my mid-thirties. (Who am I kidding? I still do!)

Are you hoping to tie this book into the Frankenstein bicentennial celebrations?

Illustrated children’s books have very long time lines from concept to finished book. I wrote Monster Science several years ago, before I had any notion of Frankenstein bicentennials. But now that we’ve arrived at this auspicious date, I’m excited! I’d love to participate in some way. I will put on my zzz zzzz zzzt thinking cap.

Where can your fans come to a reading or some other event?

I do dozens of school visits and festival events every year. Some of them might be focused on a specific book, like Monster Science, but most usually feature discussions around several of my titles. This holiday season, for example, I will be doing events around my latest picture book, a very Canadian Christmas-themed title called Deck the Halls. It’s the third in a very popular series. Anyone can drop in to the Sherway Gardens branch of Indigo Book Store [in Toronto] at noon on Sunday, Dec. 4 [2016], to take part in that.

I’ll be doing many events in association with the Forest of Reading, one of North America’s largest children’s choice award programs this spring. More than 250,000 children participate! I am honored to have two science-related books nominated this year, Worms for Breakfast: How to Feed a Zoo (Owlkids) and Everything: Space (National Geographic Kids). I will also be the keynote at the Killaloe Literary Festival in beautiful northern Ontario at the end of May. Best place to look for my latest book and schedule info is my blog, http://helainebecker.blogspot.ca/.

Is there anything you’d like to add?

For insiders only: Coming soon! Look for my upcoming picture book biography of William Playfair, the Victorian era scoundrel who single-handedly invented the field of infographics. It’s called Lines, Bars and Circles and will be published by Kids Can Press early in 2017.

Thank you, Helaine! (I usually don’t get funny interviews. It makes for a good change of pace.)

Getting back to ‘Monster Science’, you can purchase the book here.

Vitamin-driven lithium-ion battery from the University of Toronto

It seems vitamins aren’t just good for health, they’re also good for batteries. My Aug. 2, 2016 post on vitamins and batteries focused on work from Harvard, this time the work is from the University of Toronto (Canada). From an Aug. 3, 2016 news item on ScienceDaily,

A team of University of Toronto chemists has created a battery that stores energy in a biologically derived unit, paving the way for cheaper consumer electronics that are easier on the environment.

The battery is similar to many commercially-available high-energy lithium-ion batteries with one important difference. It uses flavin from vitamin B2 as the cathode: the part that stores the electricity that is released when connected to a device.

“We’ve been looking to nature for a while to find complex molecules for use in a number of consumer electronics applications,” says Dwight Seferos, an associate professor in U of T’s Department of Chemistry and Canada Research Chair in Polymer Nanotechnology.

“When you take something made by nature that is already complex, you end up spending less time making new material,” says Seferos.

An Aug. 2, 2016 University of Toronto news release (also on EurekAlert) by Peter McMahon, which originated the news item, explains further,

To understand the discovery, it’s important to know that modern batteries contain three basic parts:

  • a positive terminal – the metal part that touches devices to power them – connected to a cathode inside the battery casing
  • a negative terminal connected to an anode inside the battery casing
  • an electrolyte solution, in which ions can travel between the cathode and anode electrodes

When a battery is connected to a phone, iPod, camera or other device that requires power, electrons flow from the anode – the negatively charged electrode of the device supplying current – out to the device, then into the cathode and ions migrate through the electrolyte solution to balance the charge. When connected to a charger, this process happens in reverse.

The reaction in the anode creates electrons and the reaction in the cathode absorbs them when discharging. The net product is electricity. The battery will continue to produce electricity until one or both of the electrodes run out of the substance necessary for the reactions to occur.

Organic chemistry is kind of like Lego

While bio-derived battery parts have been created previously, this is the first one that uses bio-derived polymers – long-chain molecules – for one of the electrodes, essentially allowing battery energy to be stored in a vitamin-created plastic, instead of costlier, harder to process, and more environmentally-harmful metals such as cobalt.

“Getting the right material evolved over time and definitely took some test reactions,” says paper co-author and doctoral student Tyler Schon. “In a lot of ways, it looked like this could have failed. It definitely took a lot of perseverance.”

Schon, Seferos and colleagues happened upon the material while testing a variety of long-chain polymers – specifically pendant group polymers: the molecules attached to a ‘backbone’ chain of a long molecule.

“Organic chemistry is kind of like Lego,” he says. “You put things together in a certain order, but some things that look like they’ll fit together on paper don’t in reality. We tried a few approaches and the fifth one worked,” says Seferos.

Building a better power pack

The team created the material from vitamin B2 that originates in genetically-modified fungi using a semi-synthetic process to prepare the polymer by linking two flavin units to a long-chain molecule backbone.

This allows for a green battery with high capacity and high voltage – something increasingly important as the ‘Internet of Things’ continues to link us together more and more through our battery-powered portable devices.

“It’s a pretty safe, natural compound,” Seferos adds. “If you wanted to, you could actually eat the source material it comes from.”

B2’s ability to be reduced and oxidized makes its well-suited for a lithium ion battery.

“B2 can accept up to two electrons at a time,” says Seferos. “This makes it easy to take multiple charges and have a high capacity compared to a lot of other available molecules.”

A step to greener electronics

“It’s been a lot of trial-and-error,” says Schon. “Now we’re looking to design new variants that can be recharged again and again.”

While the current prototype is on the scale of a hearing aid battery, the team hopes their breakthrough could lay the groundwork for powerful, thin, flexible, and even transparent metal-free batteries that could support the next wave of consumer electronics.

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

Bio-Derived Polymers for Sustainable Lithium-Ion Batteries by Tyler B. Schon, Andrew J. Tilley, Colin R. Bridges, Mark B. Miltenburg, and Dwight S. Seferos. Advanced Functional Materials DOI: 10.1002/adfm.201602114 Version of Record online: 14 JUL 2016

© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This paper is behind a paywall.

Osmotic power: electricity generated with water, salt and a 3-atoms-thick membrane

EPFL researchers have developed a system that generates electricity from osmosis with unparalleled efficiency. Their work, featured in “Nature”, uses seawater, fresh water, and a new type of membrane just three atoms thick.

A July 13, 2016 news item on Nanowerk highlights  research on osmotic power at École polytechnique fédérale de Lausanne (EPFL; Switzerland),

Proponents of clean energy will soon have a new source to add to their existing array of solar, wind, and hydropower: osmotic power. Or more specifically, energy generated by a natural phenomenon occurring when fresh water comes into contact with seawater through a membrane.

Researchers at EPFL’s Laboratory of Nanoscale Biology have developed an osmotic power generation system that delivers never-before-seen yields. Their innovation lies in a three atoms thick membrane used to separate the two fluids. …

A July 14, 2016 EPFL press release (also on EurekAlert but published July 13, 2016), which originated the news item, describes the research,

The concept is fairly simple. A semipermeable membrane separates two fluids with different salt concentrations. Salt ions travel through the membrane until the salt concentrations in the two fluids reach equilibrium. That phenomenon is precisely osmosis.

If the system is used with seawater and fresh water, salt ions in the seawater pass through the membrane into the fresh water until both fluids have the same salt concentration. And since an ion is simply an atom with an electrical charge, the movement of the salt ions can be harnessed to generate electricity.

A 3 atoms thick, selective membrane that does the job

EPFL’s system consists of two liquid-filled compartments separated by a thin membrane made of molybdenum disulfide. The membrane has a tiny hole, or nanopore, through which seawater ions pass into the fresh water until the two fluids’ salt concentrations are equal. As the ions pass through the nanopore, their electrons are transferred to an electrode – which is what is used to generate an electric current.

Thanks to its properties the membrane allows positively-charged ions to pass through, while pushing away most of the negatively-charged ones. That creates voltage between the two liquids as one builds up a positive charge and the other a negative charge. This voltage is what causes the current generated by the transfer of ions to flow.

“We had to first fabricate and then investigate the optimal size of the nanopore. If it’s too big, negative ions can pass through and the resulting voltage would be too low. If it’s too small, not enough ions can pass through and the current would be too weak,” said Jiandong Feng, lead author of the research.

What sets EPFL’s system apart is its membrane. In these types of systems, the current increases with a thinner membrane. And EPFL’s membrane is just a few atoms thick. The material it is made of – molybdenum disulfide – is ideal for generating an osmotic current. “This is the first time a two-dimensional material has been used for this type of application,” said Aleksandra Radenovic, head of the laboratory of Nanoscale Biology

Powering 50’000 energy-saving light bulbs with 1m2 membrane

The potential of the new system is huge. According to their calculations, a 1m2 membrane with 30% of its surface covered by nanopores should be able to produce 1MW of electricity – or enough to power 50,000 standard energy-saving light bulbs. And since molybdenum disulfide (MoS2) is easily found in nature or can be grown by chemical vapor deposition, the system could feasibly be ramped up for large-scale power generation. The major challenge in scaling-up this process is finding out how to make relatively uniform pores.

Until now, researchers have worked on a membrane with a single nanopore, in order to understand precisely what was going on. ” From an engineering perspective, single nanopore system is ideal to further our fundamental understanding of 8=-based processes and provide useful information for industry-level commercialization”, said Jiandong Feng.

The researchers were able to run a nanotransistor from the current generated by a single nanopore and thus demonstrated a self-powered nanosystem. Low-power single-layer MoS2 transistors were fabricated in collaboration with Andras Kis’ team at at EPFL, while molecular dynamics simulations were performed by collaborators at University of Illinois at Urbana–Champaign

Harnessing the potential of estuaries

EPFL’s research is part of a growing trend. For the past several years, scientists around the world have been developing systems that leverage osmotic power to create electricity. Pilot projects have sprung up in places such as Norway, the Netherlands, Japan, and the United States to generate energy at estuaries, where rivers flow into the sea. For now, the membranes used in most systems are organic and fragile, and deliver low yields. Some systems use the movement of water, rather than ions, to power turbines that in turn produce electricity.

Once the systems become more robust, osmotic power could play a major role in the generation of renewable energy. While solar panels require adequate sunlight and wind turbines adequate wind, osmotic energy can be produced just about any time of day or night – provided there’s an estuary nearby.

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

Single-layer MoS2 nanopores as nanopower generators by Jiandong Feng, Michael Graf, Ke Liu, Dmitry Ovchinnikov, Dumitru Dumcenco, Mohammad Heiranian, Vishal Nandigana, Narayana R. Aluru, Andras Kis, & Aleksandra Radenovic. Nature (2016)  doi:10.1038/nature18593 Published online 13 July 2016

This paper is behind a paywall.