Tag Archives: carbon nanotubes

Shape memory in a supercapacitor fibre for ‘smart’ textiles (wearable tech: 1 of 3)

Wearable technology seems to be quite trendy for a grouping not usually seen: consumers, fashion designers, medical personnel, manufacturers, and scientists.

The first in this informal series concerns a fibre with memory shape. From a Nov. 19, 2015 news item on Nanowerk (Note: A link has been removed),

Wearing your mobile phone display on your jacket sleeve or an EKG probe in your sports kit are not off in some distant imagined future. Wearable “electronic textiles” are on the way. In the journal Angewandte Chemie (“A Shape-Memory Supercapacitor Fiber”), Chinese researchers have now introduced a new type of fiber-shaped supercapacitor for energy-storage textiles. Thanks to their shape memory, these textiles could potentially adapt to different body types: shapes formed by stretching and bending remain “frozen”, but can be returned to their original form or reshaped as desired.

A Nov. 19, 2015 Wiley Publishers press release, which originated the news item, provides context and detail about the work,

Any electronic components designed to be integrated into textiles must be stretchable and bendable. This is also true of the supercapacitors that are frequently used for data preservation in static storage systems (SRAM). SRAM is a type of storage that holds a small amount of data that is rapidly retrievable. It is often used for caches in processors or local storage on chips in devices whose data must be stored for long periods without a constant power supply. Some time ago, a team headed by Huisheng Peng at Fudan University developed stretchable, pliable fiber-shaped supercapacitors for integration into electronic textiles. Peng and his co-workers have now made further progress: supercapacitor fibers with shape memory.

Any electronic components designed to be integrated into textiles must be stretchable and bendable. This is also true of the supercapacitors that are frequently used for data preservation in static storage systems (SRAM). SRAM is a type of storage that holds a small amount of data that is rapidly retrievable. It is often used for caches in processors or local storage on chips in devices whose data must be stored for long periods without a constant power supply.
Some time ago, a team headed by Huisheng Peng at Fudan University developed stretchable, pliable fiber-shaped supercapacitors for integration into electronic textiles. Peng and his co-workers have now made further progress: supercapacitor fibers with shape memory.

The fibers are made using a core of polyurethane fiber with shape memory. This fiber is wrapped with a thin layer of parallel carbon nanotubes like a sheet of paper. This is followed by a coating of electrolyte gel, a second sheet of carbon nanotubes, and a final layer of electrolyte gel. The two layers of carbon nanotubes act as electrodes for the supercapacitor. Above a certain temperature, the fibers produced in this process can be bent as desired and stretched to twice their original length. The new shape can be “frozen” by cooling. Reheating allows the fibers to return to their original shape and size, after which they can be reshaped again. The electrochemical performance is fully maintained through all shape changes.

Weaving the fibers into tissues results in “smart” textiles that could be tailored to fit the bodies of different people. This could be used to make precisely fitted but reusable electronic monitoring systems for patients in hospitals, for example. The perfect fit should render them both more comfortable and more reliable.

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

A Shape-Memory Supercapacitor Fiber by Jue Deng, Ye Zhang, Yang Zhao, Peining Chen, Dr. Xunliang Cheng, & Prof. Dr. Huisheng Peng. Angewandte Chemie International Edition  DOI: 10.1002/anie.201508293  First published: 3 November 2015

This paper is behind a paywall.

The sense of touch via artificial skin

Scientists have been working for years to allow artificial skin to transmit what the brain would recognize as the sense of touch. For anyone who has lost a limb and gotten a prosthetic replacement, the loss of touch is reputedly one of the more difficult losses to accept. The sense of touch is also vital in robotics if the field is to expand and include activities reliant on the sense of touch, e.g., how much pressure do you use to grasp a cup; how much strength  do you apply when moving an object from one place to another?

For anyone interested in the ‘electronic skin and pursuit of touch’ story, I have a Nov. 15, 2013 posting which highlights the evolution of the research into e-skin and what was then some of the latest work.

This posting is a 2015 update of sorts featuring the latest e-skin research from Stanford University and Xerox PARC. (Dexter Johnson in an Oct. 15, 2015 posting on his Nanoclast blog (on the IEEE [Institute of Electrical and Electronics Engineering] site) provides a good research summary.) For anyone with an appetite for more, there’s this from an Oct. 15, 2015 American Association for the Advancement of Science (AAAS) news release on EurekAlert,

Using flexible organic circuits and specialized pressure sensors, researchers have created an artificial “skin” that can sense the force of static objects. Furthermore, they were able to transfer these sensory signals to the brain cells of mice in vitro using optogenetics. For the many people around the world living with prosthetics, such a system could one day allow them to feel sensation in their artificial limbs. To create the artificial skin, Benjamin Tee et al. developed a specialized circuit out of flexible, organic materials. It translates static pressure into digital signals that depend on how much mechanical force is applied. A particular challenge was creating sensors that can “feel” the same range of pressure that humans can. Thus, on the sensors, the team used carbon nanotubes molded into pyramidal microstructures, which are particularly effective at tunneling the signals from the electric field of nearby objects to the receiving electrode in a way that maximizes sensitivity. Transferring the digital signal from the artificial skin system to the cortical neurons of mice proved to be another challenge, since conventional light-sensitive proteins used in optogenetics do not stimulate neural spikes for sufficient durations for these digital signals to be sensed. Tee et al. therefore engineered new optogenetic proteins able to accommodate longer intervals of stimulation. Applying these newly engineered optogenic proteins to fast-spiking interneurons of the somatosensory cortex of mice in vitro sufficiently prolonged the stimulation interval, allowing the neurons to fire in accordance with the digital stimulation pulse. These results indicate that the system may be compatible with other fast-spiking neurons, including peripheral nerves.

And, there’s an Oct. 15, 2015 Stanford University news release on EurkeAlert describing this work from another perspective,

The heart of the technique is a two-ply plastic construct: the top layer creates a sensing mechanism and the bottom layer acts as the circuit to transport electrical signals and translate them into biochemical stimuli compatible with nerve cells. The top layer in the new work featured a sensor that can detect pressure over the same range as human skin, from a light finger tap to a firm handshake.

Five years ago, Bao’s [Zhenan Bao, a professor of chemical engineering at Stanford,] team members first described how to use plastics and rubbers as pressure sensors by measuring the natural springiness of their molecular structures. They then increased this natural pressure sensitivity by indenting a waffle pattern into the thin plastic, which further compresses the plastic’s molecular springs.

To exploit this pressure-sensing capability electronically, the team scattered billions of carbon nanotubes through the waffled plastic. Putting pressure on the plastic squeezes the nanotubes closer together and enables them to conduct electricity.

This allowed the plastic sensor to mimic human skin, which transmits pressure information as short pulses of electricity, similar to Morse code, to the brain. Increasing pressure on the waffled nanotubes squeezes them even closer together, allowing more electricity to flow through the sensor, and those varied impulses are sent as short pulses to the sensing mechanism. Remove pressure, and the flow of pulses relaxes, indicating light touch. Remove all pressure and the pulses cease entirely.

The team then hooked this pressure-sensing mechanism to the second ply of their artificial skin, a flexible electronic circuit that could carry pulses of electricity to nerve cells.

Importing the signal

Bao’s team has been developing flexible electronics that can bend without breaking. For this project, team members worked with researchers from PARC, a Xerox company, which has a technology that uses an inkjet printer to deposit flexible circuits onto plastic. Covering a large surface is important to making artificial skin practical, and the PARC collaboration offered that prospect.

Finally the team had to prove that the electronic signal could be recognized by a biological neuron. It did this by adapting a technique developed by Karl Deisseroth, a fellow professor of bioengineering at Stanford who pioneered a field that combines genetics and optics, called optogenetics. Researchers bioengineer cells to make them sensitive to specific frequencies of light, then use light pulses to switch cells, or the processes being carried on inside them, on and off.

For this experiment the team members engineered a line of neurons to simulate a portion of the human nervous system. They translated the electronic pressure signals from the artificial skin into light pulses, which activated the neurons, proving that the artificial skin could generate a sensory output compatible with nerve cells.

Optogenetics was only used as an experimental proof of concept, Bao said, and other methods of stimulating nerves are likely to be used in real prosthetic devices. Bao’s team has already worked with Bianxiao Cui, an associate professor of chemistry at Stanford, to show that direct stimulation of neurons with electrical pulses is possible.

Bao’s team envisions developing different sensors to replicate, for instance, the ability to distinguish corduroy versus silk, or a cold glass of water from a hot cup of coffee. This will take time. There are six types of biological sensing mechanisms in the human hand, and the experiment described in Science reports success in just one of them.

But the current two-ply approach means the team can add sensations as it develops new mechanisms. And the inkjet printing fabrication process suggests how a network of sensors could be deposited over a flexible layer and folded over a prosthetic hand.

“We have a lot of work to take this from experimental to practical applications,” Bao said. “But after spending many years in this work, I now see a clear path where we can take our artificial skin.”

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

A skin-inspired organic digital mechanoreceptor by Benjamin C.-K. Tee, Alex Chortos, Andre Berndt, Amanda Kim Nguyen, Ariane Tom, Allister McGuire, Ziliang Carter Lin, Kevin Tien, Won-Gyu Bae, Huiliang Wang, Ping Mei, Ho-Hsiu Chou, Bianxiao Cui, Karl Deisseroth, Tse Nga Ng, & Zhenan Bao. Science 16 October 2015 Vol. 350 no. 6258 pp. 313-316 DOI: 10.1126/science.aaa9306

This paper is behind a paywall.

At the root of nanotechnology: advances in dentistry

I couldn’t resist the dental wordplay in my headline. Strictly speaking this posting features a research paper that is looking into dentistry’s nanotechnology-enabled future. From an Oct. 19, 2015 news item on phys.org,

Have a cavity? Ask your dentist about filling it with a mixture of nanoparticles including silica and zirconia. These white fillings (known as nano-composite resins) resemble teeth better than their metal alternatives and are less likely to come loose or fracture teeth. This is just the beginning argue Brazilian scientists in a review of “nanodentistry,” published October 19 [2015] in Trends in Biotechnology. Next-generation dental materials incorporating nanotechnology aim to help teeth self-heal, rebuild enamel, and protect against bacterial infections.

An Oct. 19, 2015 Cell Press news release on EurekAlert, which originated the news item, expands on the theme,

“Nanotechnology can be faced sometimes as a paradigm that promised a lot and delivered very little,” says senior author Nelson Durán of the Universidade Estadual de Campinas. “The evolution of dental materials though nanotechnology is real and remarkable, reflecting on a billionaire market. In this way, dentistry was in fact one of the most benefited areas from the development of nanotechnology.”

Since the introduction of nano-composite resins a decade ago, engineers have been exploring how else nanotechnology can safely be used in the dentist’s office. Products could include antimicrobial adhesives made up of carbon nanotubes–creating a kind of wearable toothpaste–or quantum dots combined with cancer-specific antibodies that can be applied inside the mouth, emitting light if they detect any troublesome cells.

“The remineralization of enamel and dentin with the use of nanoparticles (incorporated in different vehicles), a key issue for improving the quality and longevity of resin restorations, is being currently investigated,” says co-author Amauri Jardim de Paula of Universidade Federal do Ceará. “A future perspective is that nanoparticles incorporated in dental materials will prevent and/or control oral diseases through their long-term release and action.”

Although nanodental technologies have evolved quickly, safety and cost will be barriers to getting them on the market. Some nanomaterials might be toxic to healthy cells, so any new nanomaterials to be used for dentistry would need formal pre-clinical and clinical trials before they can receive approval. Patients will also need to be told that a treatment will use materials in the nanometer size range and should be aware of any possible side effects. This new technology could also be expensive, and insurance companies may not want to foot the bill if treatments could be considered cosmetic; composite resins, for example, are still an out-of-pocket cost.

The review authors believe these hurdles can be overcome, however, and that new nanodental products should be available within a few years.

The research has been illustrated,

Caption: This schematic represents the current use and perspectives on the use of nanomaterials on therapeutic dentistry. Credit: Padovania et al./Trends in Biotechnology 2015

Caption: This schematic represents the current use and perspectives on the use of nanomaterials on therapeutic dentistry.
Credit: Padovania et al./Trends in Biotechnology 2015

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

Advances in Dental Materials through Nanotechnology: Facts, Perspectives and Toxicological Aspects by Gislaine C. Padovani, Victor P. Feitosa, Salvatore Sauro, Franklin R. Tay, Gabriela Durán, Amauri J. Paula, & Nelson Durán. Trends in Biotechnology – Cell DOI: http://dx.doi.org/10.1016/j.tibtech.2015.09.005 Publication stage: In Press Corrected Proof Published online Oct. 19, 2015

The paper appears to be open access.

Inadvertent carbon nanotube production from your car

It’s disconcerting to find out that cars inadvertently produce carbon nanotubes which are then spilled into the air we breathe. Researchers at Rice University (US) and Paris-Saclay University (France) have examined matter from car exhausts and dust in various parts of Paris finding carbon nanotubes (CNTs). Further, they also studied the lungs of Parisian children who have asthma and found CNTs there too.

The scientists have carefully stated that CNTs have been observed in lung cells but they are not claiming causality (i.e., they don’t claim the children’s asthma was caused by CNTs).

An Oct. 20, 2015 news item on Nanotechnology Now introduces the research,

Cars appear to produce carbon nanotubes, and some of the evidence has been found in human lungs.

Rice University scientists working with colleagues in France have detected the presence of man-made carbon nanotubes in cells extracted from the airways of Parisian children under routine treatment for asthma. Further investigation found similar nanotubes in samples from the exhaust pipes of Paris vehicles and in dust gathered from various places around the city.

The researchers reported in the journal EBioMedicine this month that these samples align with what has been found elsewhere, including Rice’s home city of Houston, in spider webs in India and in ice cores.

An Oct. 19, 2015 Rice University news release (also on EurekAlert), which originated the news item, painstakingly describes the work and initial conclusions,

The research in no way ascribes the children’s conditions to the nanotubes, said Rice chemist Lon Wilson, a corresponding author of the new paper. But the nanotubes’ apparent ubiquity should be the focus of further investigation, he said.

“We know that carbon nanoparticles are found in nature,” Wilson said, noting that round fullerene molecules like those discovered at Rice are commonly produced by volcanoes, forest fires and other combustion of carbon materials. “All you need is a little catalysis to make carbon nanotubes instead of fullerenes.”

A car’s catalytic converter, which turns toxic carbon monoxide into safer emissions, bears at least a passing resemblance to the Rice-invented high-pressure carbon monoxide, or HiPco, process to make carbon nanotubes, he said. “So it is not a big surprise, when you think about it,” Wilson said.

The team led by Wilson, Fathi Moussa of Paris-Saclay University and lead author Jelena Kolosnjaj-Tabi, a graduate student at Paris-Saclay, analyzed particulate matter found in the alveolar macrophage cells (also known as dust cells) that help stop foreign materials like particles and bacteria from entering the lungs.

The researchers wrote that their results “suggest humans are routinely exposed” to carbon nanotubes. They also suggested previous studies that link the carbon content of airway macrophages and the decline of lung function should be reconsidered in light of the new findings. Moussa confirmed his lab will continue to study the impact of man-made nanotubes on health.

The cells were taken from 69 randomly selected asthma patients aged 2 to 17 who underwent routine fiber-optic bronchoscopies as part of their treatment. For ethical reasons, no cells from healthy patients were analyzed, but because nanotubes were found in all of the samples, the study led the researchers to conclude that carbon nanotubes are likely to be found in everybody.

The study notes but does not make definitive conclusions about the controversial proposition that carbon nanotube fibers may act like asbestos, a proven carcinogen. But the authors reminded that “long carbon nanotubes and large aggregates of short ones can induce a granulomatous (inflammation) reaction.”

The study partially answers the question of what makes up the black material inside alveolar macrophages, the original focus of the study. The researchers found single-walled and multiwalled carbon nanotubes and amorphous carbon among the cells, as well as in samples swabbed from the tailpipes of cars in Paris and dust from various buildings in and around the city.

The news release goes on to detail how the research was conducted,

“The concentrations of nanotubes are so low in these samples that it’s hard to believe they would cause asthma, but you never know,” Wilson said. “What surprised me the most was that carbon nanotubes were the major component of the carbonaceous pollution we found in the samples.”

The nanotube aggregates in the cells ranged in size from 10 to 60 nanometers in diameter and up to several hundred nanometers in length, small enough that optical microscopes would not have been able to identify them in samples from former patients. The new study used more sophisticated tools, including high-resolution transmission electron microscopy, X-ray spectroscopy, Raman spectroscopy and near-infrared fluorescence microscopy to definitively identify them in the cells and in the environmental samples.

“We collected samples from the exhaust pipes of cars in Paris as well as from busy and non-busy intersections there and found the same type of structures as in the human samples,” Wilson said.

“It’s kind of ironic. In our laboratory, working with carbon nanotubes, we wear facemasks to prevent exactly what we’re seeing in these samples, yet everyone walking around out there in the world probably has at least a small concentration of carbon nanotubes in their lungs,” he said.

The researchers also suggested that the large surface areas of nanotubes and their ability to adhere to substances may make them effective carriers for other pollutants.

The study followed one released by Rice and Baylor College of Medicine earlier this month with the similar goal of analyzing the black substance found in the lungs of smokers who died of emphysema. That study found carbon black nanoparticles that were the product of the incomplete combustion of such organic material as tobacco.

Here’s an image of a sample,

 Caption: Carbon nanotubes (the long rods) and nanoparticles (the black clumps) appear in vehicle exhaust taken from the tailpipes of cars in Paris. The image is part of a study by scientists in Paris and at Rice University to analyze carbonaceous material in the lungs of asthma patients. They found that cars are a likely source of nanotubes found in the patients. Credit: Courtesy of Fathi Moussa/Paris-Saclay University

Caption: Carbon nanotubes (the long rods) and nanoparticles (the black clumps) appear in vehicle exhaust taken from the tailpipes of cars in Paris. The image is part of a study by scientists in Paris and at Rice University to analyze carbonaceous material in the lungs of asthma patients. They found that cars are a likely source of nanotubes found in the patients.
Credit: Courtesy of Fathi Moussa/Paris-Saclay University

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

Anthropogenic Carbon Nanotubes Found in the Airways of Parisian Children by Jelena Kolosnjaj-Tabi, Jocelyne Just, Keith B. Hartman, Yacine Laoudi, Sabah Boudjemaa, Damien Alloyeau, Henri Szwarc, Lon J. Wilson, & Fathi Moussa. EBioMedicine doi:10.1016/j.ebiom.2015.10.012 Available online 9 October 2015

This paper is open access.

ETA Oct. 26, 2015: Dexter Johnson, along with Dr. Andrew Maynard, provides an object lesson on how to read science research in an Oct. 23, 2015 posting on his Nanoclast blog (on the IEEE [Institute of Electrical and Electronics Engineers]),

“From past studies, the conditions in combustion engines seem to favor the production of at least some CNTs (especially where there are trace metals in lubricants that can act as catalysts for CNT growth),” explained Andrew Maynard Director, Risk Innovation Lab and Professor, School for the Future of Innovation in Society at Arizona State University, in an e-mail interview. Says Maynard:

What, to my knowledge, is still not known, is the relative concentrations of CNT in ambient air that may be inhaled, the precise nature of these CNT in terms of physical and chemical structure, and the range of sources that may lead to ambient CNT. This is important, as the potential for fibrous particles to cause lung damage depends on characteristics such as their length—and many of the fibers shown in the paper appear too short to raise substantial concerns.”

Nonetheless, Maynard praises the research for establishing that these carbon nanotube-like fibers are part of the urban aerosol and therefore end up in the lungs of anyone who breathes it in. However, he cautions that the findings don’t provide information on the potential health risks associated with these exposures.

It’s a good read not only for the information but the mild snarkiness (assuming you find that kind of thing amusing) that spices up the piece.

IBM, the Cognitive Era, and carbon nanotube electronics

IBM has a storied position in the field of nanotechnology due to the scanning tunneling microscope developed in the company’s laboratories. It was a Nobel Prize-winning breakthough which provided the impetus for nanotechnology applied research. Now, an Oct. 1, 2015 news item on Nanowerk trumpets another IBM breakthrough,

IBM Research today [Oct. 1, 2015] announced a major engineering breakthrough that could accelerate carbon nanotubes replacing silicon transistors to power future computing technologies.

IBM scientists demonstrated a new way to shrink transistor contacts without reducing performance of carbon nanotube devices, opening a pathway to dramatically faster, smaller and more powerful computer chips beyond the capabilities of traditional semiconductors.

While the Oct. 1, 2015 IBM news release, which originated the news item, does go on at length there’s not much technical detail (see the second to last paragraph in the excerpt for the little they do include) about the research breakthrough (Note: Links have been removed),

IBM’s breakthrough overcomes a major hurdle that silicon and any semiconductor transistor technologies face when scaling down. In any transistor, two things scale: the channel and its two contacts. As devices become smaller, increased contact resistance for carbon nanotubes has hindered performance gains until now. These results could overcome contact resistance challenges all the way to the 1.8 nanometer node – four technology generations away. [emphasis mine]

Carbon nanotube chips could greatly improve the capabilities of high performance computers, enabling Big Data to be analyzed faster, increasing the power and battery life of mobile devices and the Internet of Things, and allowing cloud data centers to deliver services more efficiently and economically.

Silicon transistors, tiny switches that carry information on a chip, have been made smaller year after year, but they are approaching a point of physical limitation. With Moore’s Law running out of steam, shrinking the size of the transistor – including the channels and contacts – without compromising performance has been a vexing challenge troubling researchers for decades.

IBM has previously shown that carbon nanotube transistors can operate as excellent switches at channel dimensions of less than ten nanometers – the equivalent to 10,000 times thinner than a strand of human hair and less than half the size of today’s leading silicon technology. IBM’s new contact approach overcomes the other major hurdle in incorporating carbon nanotubes into semiconductor devices, which could result in smaller chips with greater performance and lower power consumption.

Earlier this summer, IBM unveiled the first 7 nanometer node silicon test chip [emphasis mine], pushing the limits of silicon technologies and ensuring further innovations for IBM Systems and the IT industry. By advancing research of carbon nanotubes to replace traditional silicon devices, IBM is paving the way for a post-silicon future and delivering on its $3 billion chip R&D investment announced in July 2014.

“These chip innovations are necessary to meet the emerging demands of cloud computing, Internet of Things and Big Data systems,” said Dario Gil, vice president of Science & Technology at IBM Research. “As silicon technology nears its physical limits, new materials, devices and circuit architectures must be ready to deliver the advanced technologies that will be required by the Cognitive Computing era. This breakthrough shows that computer chips made of carbon nanotubes will be able to power systems of the future sooner than the industry expected.”

A New Contact for Carbon Nanotubes

Carbon nanotubes represent a new class of semiconductor materials that consist of single atomic sheets of carbon rolled up into a tube. The carbon nanotubes form the core of a transistor device whose superior electrical properties promise several generations of technology scaling beyond the physical limits of silicon.

Electrons in carbon transistors can move more easily than in silicon-based devices, and the ultra-thin body of carbon nanotubes provide additional advantages at the atomic scale. Inside a chip, contacts are the valves that control the flow of electrons from metal into the channels of a semiconductor. As transistors shrink in size, electrical resistance increases within the contacts, which impedes performance. Until now, decreasing the size of the contacts on a device caused a commensurate drop in performance – a challenge facing both silicon and carbon nanotube transistor technologies.

IBM researchers had to forego traditional contact schemes and invented a metallurgical process akin to microscopic welding that chemically binds the metal atoms to the carbon atoms at the ends of nanotubes. This ‘end-bonded contact scheme’ allows the contacts to be shrunken down to below 10 nanometers without deteriorating performance of the carbon nanotube devices.

“For any advanced transistor technology, the increase in contact resistance due to the decrease in the size of transistors becomes a major performance bottleneck,” Gil added. “Our novel approach is to make the contact from the end of the carbon nanotube, which we show does not degrade device performance. This brings us a step closer to the goal of a carbon nanotube technology within the decade.”

Every once in a while, the size gets to me and a 1.8nm node is amazing. As for IBM’s 7nm chip, which was previewed this summer, there’s more about that in my July 15, 2015 posting.

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

End-bonded contacts for carbon nanotube transistors with low, size-independent resistance by Qing Cao, Shu-Jen Han, Jerry Tersoff, Aaron D. Franklin†, Yu Zhu, Zhen Zhang‡, George S. Tulevski, Jianshi Tang, and Wilfried Haensch. Science 2 October 2015: Vol. 350 no. 6256 pp. 68-72 DOI: 10.1126/science.aac8006

This paper is behind a paywall.

Commercializing nanotechnology: Peter Thiel’s Breakout Labs and Argonne National Laboratories

Breakout Labs

I last wrote about entrepreneur Peter Thiel’s Breakout Labs project in an Oct. 26, 2011 posting announcing its inception. An Oct. 6, 2015 Breakout Labs news release (received in my email) highlights a funding announcement for four startups of which at least three are nanotechnology-enabled,

Breakout Labs, a program of Peter Thiel’s philanthropic organization, the Thiel Foundation, announced today that four new companies advancing scientific discoveries in biomedical, chemical engineering, and nanotechnology have been selected for funding.

“We’re always hearing about bold new scientific research that promises to transform the world, but far too often the latest discoveries are left withering in a lab,” said Lindy Fishburne, Executive Director of Breakout Labs. “Our mission is to help a new type of scientist-entrepreneur navigate the startup ecosystem and build lasting companies that can make audacious scientific discoveries meaningful to everyday life. The four new companies joining the Breakout Labs portfolio – nanoGriptech, Maxterial, C2Sense, and CyteGen – embody that spirit and we’re excited to be working with them to help make their vision a reality.”

The future of adhesives: inspired by geckos

Inspired by the gecko’s ability to scuttle up walls and across ceilings due to their millions of micro/nano foot-hairs,nanoGriptech (http://nanogriptech.com/), based in Pittsburgh, Pa., is developing a new kind of microfiber adhesive material that is strong, lightweight, and reusable without requiring glues or producing harmful residues. Currently being tested by the U.S. military, NASA, and top global brands, nanoGriptech’s flagship product Setex™ is the first adhesive product of its kind that is not only strong and durable, but can also be manufactured at low cost, and at scale.

“We envision a future filled with no-leak biohazard enclosures, ergonomic and inexpensive car seats, extremely durable aerospace adhesives, comfortable prosthetic liners, high performance athletic wear, and widely available nanotechnology-enabled products manufactured less expensively — all thanks to the grippy little gecko,” said Roi Ben-Itzhak, CFO and VP of Business Development for nanoGriptech.

A sense of smell for the digital world

Despite the U.S. Department of Agriculture’s recent goals to drastically reduce food waste, most consumers don’t realize the global problem created by 1.3 billion metric tons of food wasted each year — clogging landfills and releasing unsustainable levels of methane gas into the atmosphere. Using technology developed at MIT’s Swager lab, Cambridge, Ma.-based C2Sense(http://www.c2sense.com/) is developing inexpensive, lightweight hand-held sensors based on carbon nanotubes which can detect fruit ripeness and meat, fish and poultry freshness. Smaller than a half of a business card, these sensors can be developed at very low cost, require very little power to operate, and can be easily integrated into most agricultural supply chains, including food storage packaging, to ensure that food is picked, stored, shipped, and sold at optimal freshness.

“Our mission is to bring a sense of smell to the digital world. With our technology, that package of steaks in your refrigerator will tell you when it’s about to go bad, recommend some recipe options and help build out your shopping list,” said Jan Schnorr, Chief Technology Officer of C2Sense.

Amazing metals that completely repel water

MaxterialTM, Inc. develops amazing materials that resist a variety of detrimental environmental effects through technology that emulates similar strategies found in nature, such as the self-cleaning lotus leaf and antifouling properties of crabs. By modifying the surface shape or texture of a metal, through a method that is very affordable and easy to introduce into the existing manufacturing process, Maxterial introduces a microlayer of air pockets that reduce contact surface area. The underlying material can be chemically the same as ever, retaining inherent properties like thermal and electrical conductivity. But through Maxterial’s technology, the metallic surface also becomes inherently water repellant. This property introduces the superhydrophobic maxterial as a potential solution to a myriad of problems, such as corrosion, biofouling, and ice formation. Maxterial is currently focused on developing durable hygienic and eco-friendly anti-corrosion coatings for metallic surfaces.

“Our process has the potential to create metallic objects that retain their amazing properties for the lifetime of the object – this isn’t an aftermarket coating that can wear or chip off,” said Mehdi Kargar, Co-founder and CEO of Maxterial, Inc. “We are working towards a day when shipping equipment can withstand harsh arctic environments, offshore structures can resist corrosion, and electronics can be fully submersible and continue working as good as new.”

New approaches to combat aging

CyteGen (http://cytegen.com/) wants to dramatically increase the human healthspan, tackle neurodegenerative diseases, and reverse age-related decline. What makes this possible now is new discovery tools backed by the dream team of interdisciplinary experts the company has assembled. CyteGen’s approach is unusually collaborative, tapping into the resources and expertise of world-renowned researchers across eight major universities to focus different strengths and perspectives to achieve the company’s goals. By approaching aging from a holistic, systematic point of view, rather than focusing solely on discrete definitions of disease, they have developed a new way to think about aging, and to develop treatments that can help people live longer, healthier lives.

“There is an assumption that aging necessarily brings the kind of physical and mental decline that results in Parkinson’s, Alzheimer’s, and other diseases. Evidence indicates otherwise, which is what spurred us to launch CyteGen,” said George Ugras, Co-Founder and President of CyteGen.

To date, Breakout Labs has invested in more than two dozen companies at the forefront of science, helping radical technologies get beyond common hurdles faced by early stage companies, and advance research and development to market much more quickly. Portfolio companies have raised more than six times the amount of capital invested in the program by the Thiel Foundation, and represent six Series A valuations ranging from $10 million to $60 million as well as one acquisition.

You can see the original Oct. 6, 2015 Breakout Labs news release here or in this Oct. 7, 2015 news item on Azonano.

Argonne National Labs and Nano Design Works (NDW) and the Argonne Collaborative Center for Energy Storage Science (ACCESS)

The US Department of Energy’s Argonne National Laboratory’s Oct. 6, 2015 press release by Greg Cunningham announced two initiatives meant to speed commercialization of nanotechnology-enabled products for the energy storage and other sectors,

Few technologies hold more potential to positively transform our society than energy storage and nanotechnology. Advances in energy storage research will revolutionize the way the world generates and stores energy, democratizing the delivery of electricity. Grid-level storage can help reduce carbon emissions through the increased adoption of renewable energy and use of electric vehicles while helping bring electricity to developing parts of the world. Nanotechnology has already transformed the electronics industry and is bringing a new set of powerful tools and materials to developers who are changing everything from the way energy is generated, stored and transported to how medicines are delivered and the way chemicals are produced through novel catalytic nanomaterials.

Recognizing the power of these technologies and seeking to accelerate their impact, the U.S. Department of Energy’s Argonne National Laboratory has created two new collaborative centers that provide an innovative pathway for business and industry to access Argonne’s unparalleled scientific resources to address the nation’s energy and national security needs. These centers will help speed discoveries to market to ensure U.S. industry maintains a lead in this global technology race.

“This is an exciting time for us, because we believe this new approach to interacting with business can be a real game changer in two areas of research that are of great importance to Argonne and the world,” said Argonne Director Peter B. Littlewood. “We recognize that delivering to market our breakthrough science in energy storage and nanotechnology can help ensure our work brings the maximum benefit to society.”

Nano Design Works (NDW) and the Argonne Collaborative Center for Energy Storage Science (ACCESS) will provide central points of contact for companies — ranging from large industrial entities to smaller businesses and startups, as well as government agencies — to benefit from Argonne’s world-class expertise, scientific tools and facilities.

NDW and ACCESS represent a new way to collaborate at Argonne, providing a single point of contact for businesses to assemble tailored interdisciplinary teams to address their most challenging R&D questions. The centers will also provide a pathway to Argonne’s fundamental research that is poised for development into practical products. The chance to build on existing scientific discovery is a unique opportunity for businesses in the nano and energy storage fields.

The center directors, Andreas Roelofs of NDW and Jeff Chamberlain of ACCESS, have both created startups in their careers and understand the value that collaboration with a national laboratory can bring to a company trying to innovate in technologically challenging fields of science. While the new centers will work with all sizes of companies, a strong emphasis will be placed on helping small businesses and startups, which are drivers of job creation and receive a large portion of the risk capital in this country.

“For a startup like mine to have the ability to tap the resources of a place like Argonne would have been immensely helpful,” said Roelofs. “We”ve seen the power of that sort of access, and we want to make it available to the companies that need it to drive truly transformative technologies to market.”

Chamberlain said his experience as an energy storage researcher and entrepreneur led him to look for innovative approaches to leveraging the best aspects of private industry and public science. The national laboratory system has a long history of breakthrough science that has worked its way to market, but shortening that journey from basic research to product has become a growing point of emphasis for the national laboratories over the past couple of decades. The idea behind ACCESS and NDW is to make that collaboration even easier and more powerful.

“Where ACCESS and NDW will differ from the conventional approach is through creating an efficient way for a business to build a customized, multi-disciplinary team that can address anything from small technical questions to broad challenges that require massive resources,” Chamberlain said. “That might mean assembling a team with chemists, physicists, computer scientists, materials engineers, imaging experts, or mechanical and electrical engineers; the list goes on and on. It’s that ability to tap the full spectrum of cross-cutting expertise at Argonne that will really make the difference.”

Chamberlain is deeply familiar with the potential of energy storage as a transformational technology, having led the formation of Argonne’s Joint Center for Energy Storage Research (JCESR). The center’s years-long quest to discover technologies beyond lithium-ion batteries has solidified the laboratory’s reputation as one of the key global players in battery research. ACCESS will tap Argonne’s full battery expertise, which extends well beyond JCESR and is dedicated to fulfilling the promise of energy storage.

Energy storage research has profound implications for energy security and national security. Chamberlain points out that approximately 1.3 billion people across the globe do not have access to electricity, with another billion having only sporadic access. Energy storage, coupled with renewable generation like solar, could solve that problem and eliminate the need to build out massive power grids. Batteries also have the potential to create a more secure, stable grid for countries with existing power systems and help fight global climate disruption through adoption of renewable energy and electric vehicles.

Argonne researchers are pursuing hundreds of projects in nanoscience, but some of the more notable include research into targeted drugs that affect only cancerous cells; magnetic nanofibers that can be used to create more powerful and efficient electric motors and generators; and highly efficient water filtration systems that can dramatically reduce the energy requirements for desalination or cleanup of oil spills. Other researchers are working with nanoparticles that create a super-lubricated state and other very-low friction coatings.

“When you think that 30 percent of a car engine’s power is sacrificed to frictional loss, you start to get an idea of the potential of these technologies,” Roelofs said. “But it’s not just about the ideas already at Argonne that can be brought to market, it’s also about the challenges for businesses that need Argonne-level resources. I”m convinced there are many startups out there working on transformational ideas that can greatly benefit from the help of a place Argonne to bring those ideas to fruition. That is what has me excited about ACCESS and NDW.”

For more information on ACCESS, see: access.anl.gov

For more information on NDW, see: nanoworks.anl.gov

You can read more about the announcement in an Oct. 6, 2015 article by Greg Watry for R&D magazine featuring an interview with Andreas Roelofs.

Cleaning up carbon dioxide pollution in the oceans and elsewhere

I have a mini roundup of items (3) concerning nanotechnology and environmental applications with a special focus on carbon materials.

Carbon-capturing motors

First up, there’s a Sept. 23, 2015 news item on ScienceDaily which describes work with tiny carbon-capturing motors,

Machines that are much smaller than the width of a human hair could one day help clean up carbon dioxide pollution in the oceans. Nanoengineers at the University of California, San Diego have designed enzyme-functionalized micromotors that rapidly zoom around in water, remove carbon dioxide and convert it into a usable solid form.

The proof of concept study represents a promising route to mitigate the buildup of carbon dioxide, a major greenhouse gas in the environment, said researchers. …

A Sept 22, 2015 University of California at San Diego (UCSD) news release by Liezel Labios, which originated the news release, provides more details about the scientists’ hopes and the technology,

“We’re excited about the possibility of using these micromotors to combat ocean acidification and global warming,” said Virendra V. Singh, a postdoctoral scientist in Wang’s [nanoengineering professor and chair Joseph Wang] research group and a co-first author of this study.

In their experiments, nanoengineers demonstrated that the micromotors rapidly decarbonated water solutions that were saturated with carbon dioxide. Within five minutes, the micromotors removed 90 percent of the carbon dioxide from a solution of deionized water. The micromotors were just as effective in a sea water solution and removed 88 percent of the carbon dioxide in the same timeframe.

“In the future, we could potentially use these micromotors as part of a water treatment system, like a water decarbonation plant,” said Kevin Kaufmann, an undergraduate researcher in Wang’s lab and a co-author of the study.

The micromotors are essentially six-micrometer-long tubes that help rapidly convert carbon dioxide into calcium carbonate, a solid mineral found in eggshells, the shells of various marine organisms, calcium supplements and cement. The micromotors have an outer polymer surface that holds the enzyme carbonic anhydrase, which speeds up the reaction between carbon dioxide and water to form bicarbonate. Calcium chloride, which is added to the water solutions, helps convert bicarbonate to calcium carbonate.

The fast and continuous motion of the micromotors in solution makes the micromotors extremely efficient at removing carbon dioxide from water, said researchers. The team explained that the micromotors’ autonomous movement induces efficient solution mixing, leading to faster carbon dioxide conversion. To fuel the micromotors in water, researchers added hydrogen peroxide, which reacts with the inner platinum surface of the micromotors to generate a stream of oxygen gas bubbles that propel the micromotors around. When released in water solutions containing as little as two to four percent hydrogen peroxide, the micromotors reached speeds of more than 100 micrometers per second.

However, the use of hydrogen peroxide as the micromotor fuel is a drawback because it is an extra additive and requires the use of expensive platinum materials to build the micromotors. As a next step, researchers are planning to make carbon-capturing micromotors that can be propelled by water.

“If the micromotors can use the environment as fuel, they will be more scalable, environmentally friendly and less expensive,” said Kaufmann.

The researchers have provided an image which illustrates the carbon-capturing motors in action,

Nanoengineers have invented tiny tube-shaped micromotors that zoom around in water and efficiently remove carbon dioxide. The surfaces of the micromotors are functionalized with the enzyme carbonic anhydrase, which enables the motors to help rapidly convert carbon dioxide to calcium carbonate. Image credit: Laboratory for Nanobioelectronics, UC San Diego Jacobs School of Engineering.

Nanoengineers have invented tiny tube-shaped micromotors that zoom around in water and efficiently remove carbon dioxide. The surfaces of the micromotors are functionalized with the enzyme carbonic anhydrase, which enables the motors to help rapidly convert carbon dioxide to calcium carbonate. Image credit: Laboratory for Nanobioelectronics, UC San Diego Jacobs School of Engineering.

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

Micromotor-Based Biomimetic Carbon Dioxide Sequestration: Towards Mobile Microscrubbers by Murat Uygun, Virendra V. Singh, Kevin Kaufmann, Deniz A. Uygun, Severina D. S. de Oliveira, and oseph Wang. Angewandte Chemie DOI: 10.1002/ange.201505155 Article first published online: 4 SEP 2015

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This article is behind a paywall.

Carbon nanotubes for carbon dioxide capture (carbon capture)

In a Sept. 22, 2015 posting by Dexter Johnson on his Nanoclast blog (located on the IEEE [Institute for Electrical and Electronics Engineers] website) describes research where carbon nanotubes are being used for carbon capture,

Now researchers at Technische Universität Darmstadt in Germany and the Indian Institute of Technology Kanpur have found that they can tailor the gas adsorption properties of vertically aligned carbon nanotubes (VACNTs) by altering their thickness, height, and the distance between them.

“These parameters are fundamental for ‘tuning’ the hierarchical pore structure of the VACNTs,” explained Mahshid Rahimi and Deepu Babu, doctoral students at the Technische Universität Darmstadt who were the paper’s lead authors, in a press release. “This hierarchy effect is a crucial factor for getting high-adsorption capacities as well as mass transport into the nanostructure. Surprisingly, from theory and by experiment, we found that the distance between nanotubes plays a much larger role in gas adsorption than the tube diameter does.”

Dexter provides a good and brief summary of the research.

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

Double-walled carbon nanotube array for CO2 and SO2 adsorption by Mahshid Rahimi, Deepu J. Babu, Jayant K. Singh, Yong-Biao Yang, Jörg J. Schneider, and Florian Müller-Plathe. J. Chem. Phys. 143, 124701 (2015); http://dx.doi.org/10.1063/1.4929609

This paper is open access.

The market for nanotechnology-enabled environmental applications

Coincident with stumbling across these two possible capture solutions, I found this Sept. 23, 2015 BCC Research news release,

A groundswell of global support for developing nanotechnology as a pollution remediation technique will continue for the foreseeable future. BCC Research reveals in its new report that this key driver, along with increasing worldwide concerns over removing pollutants and developing alternative energy sources, will drive growth in the nanotechnology environmental applications market.

The global nanotechnology market in environmental applications is expected to reach $25.7 billion by 2015 and $41.8 billion by 2020, conforming to a five-year (2015-2020) compound annual growth rate (CAGR) of 10.2%. Air remediation as a segment will reach $10.2 billion and $16.7 billion in 2015 and 2020, respectively, reflecting a five-year CAGR of 10.3%. Water remediation as a segment will grow at a five-year CAGR of 12.4% to reach $10.6 billion in 2020.

As nanoparticles push the limits and capabilities of technology, new and better techniques for pollution control are emerging. Presently, nanotechnology’s greatest potential lies in air pollution remediation.

“Nano filters could be applied to automobile tailpipes and factory smokestacks to separate out contaminants and prevent them from entering the atmosphere. In addition, nano sensors have been developed to sense toxic gas leaks at extremely low concentrations,” says BCC research analyst Aneesh Kumar. “Overall, there is a multitude of promising environmental applications for nanotechnology, with the main focus area on energy and water technologies.”

You can find links to the report, TOC (table of contents), and report overview on the BCC Research Nanotechnology in Environmental Applications: The Global Market report webpage.

Carbon nanotubes as sensors in the body

Rachel Ehrenberg has written an Aug. 21, 2015 news item about the latest and greatest carbon nanotube-based biomedical sensors for the journal Nature,

The future of medical sensors may be going down the tubes. Chemists are developing tiny devices made from carbon nanotubes wrapped with polymers to detect biologically important compounds such as insulin, nitric oxide and the blood-clotting protein fibrinogen. The hope is that these sensors could simplify and automate diagnostic tests.

Preliminary experiments in mice, reported by scientists at a meeting of the American Chemical Society in Boston, Massachusetts, this week [Aug. 16 – 20, 2015], suggest that the devices are safe to introduce into the bloodstream or implant under the skin. Researchers also presented data showing that the nanotube–polymer complexes could measure levels of large molecules, a feat that has been difficult for existing technologies.

Ehrenberg focuses on one laboratory in particular (Note: Links have been removed),

“Anything the body makes, it is meant to degrade,” says chemical engineer Michael Strano, whose lab at the Massachusetts Institute of Technology (MIT) in Cambridge is behind much of the latest work1. “Our vision is to make a sensing platform that can monitor a whole range of molecules, and do it in the long term.”

To design one sensor, MIT  researchers coated nanotubes with a mix of polymers and nucleotides and screened for configurations that would bind to the protein fibrinogen. This large molecule is important for building blood clots; its concentration can indicate bleeding disorders, liver disease or impending cardiovascular trouble. The team recently hit on a material that worked — a first for such a large molecule, according to MIT nanotechnology specialist Gili Bisker. Bisker said at the chemistry meeting that the fibrinogen-detecting nanotubes could be used to measure levels of the protein in blood samples, or implanted in body tissue to detect changing fibrinogen levels that might indicate a clot.

The MIT team has also developed2 a sensor that can be inserted beneath the skin to monitor glucose or insulin levels in real time, Bisker reported. The team imagines putting a small patch that contains a wireless device on the skin just above the embedded sensor. The patch would shine light on the sensor and measure its fluorescence, then transmit that data to a mobile phone for real-time monitoring.

Another version of the sensor, developed3 at MIT by biomedical engineer Nicole Iverson and colleagues, detects nitric oxide. This signalling molecule typically indicates inflammation and is associated with many cancer cells. When embedded in a hydrogel matrix, the sensor kept working in mice for more than 400 days and caused no local inflammation, MIT chemical engineer Michael Lee reported. The nitric oxide sensors also performed well when injected into the bloodstreams of mice, successfully passing through small capillaries in the lungs, which are an area of concern for nanotube toxicity. …

There’s at least one corporate laboratory (Google X), working on biosensors although their focus is a little different. From a Jan. 9, 2015 article by Brian Womack and Anna Edney for BloombergBusiness,

Google Inc. sent employees with ties to its secretive X research group to meet with U.S. regulators who oversee medical devices, raising the possibility of a new product that may involve biosensors from the unit that developed computerized glasses.

The meeting included at least four Google workers, some of whom have connections with Google X — and have done research on sensors, including contact lenses that help wearers monitor their biological data. Google staff met with those at the Food and Drug Administration who regulate eye devices and diagnostics for heart conditions, according to the agency’s public calendar. [emphasis mine]

This approach from Google is considered noninvasive,

“There is actually one interface on the surface of the body that can literally provide us with a window of what happens inside, and that’s the surface of the eye,” Parviz [Babak Parviz, … was involved in the Google Glass project and has talked about putting displays on contact lenses, including lenses that monitor wearer’s health]  said in a video posted on YouTube. “It’s a very interesting chemical interface.”

Of course, the assumption is that all this monitoring is going to result in  healthier people but I can’t help thinking about an old saying ‘a little knowledge can be a dangerous thing’. For example, we lived in a world where bacteria roamed free and then we learned how to make them visible, determined they were disease-causing, and began campaigns for killing them off. Now, it turns out that at least some bacteria are good for us and, moreover, we’ve created other, more dangerous bacteria that are drug-resistant. Based on the bacteria example, is it possible that with these biosensors we will observe new phenomena and make similar mistakes?

Wearable technologies, electric vehicles and conundrums at Wollongong University (Australia)

A July 25, 2015 news item on Nanowerk announces research at the University of Wollongong designed to address a conundrum (Note: A link has been removed),

UOW’s Institute for Superconducting and Electronic Materials (ISEM) has successfully pioneered a way to construct a flexible, foldable and lightweight energy storage device that provides the building blocks for next-generation batteries needed to power wearable electronics and implantable medical devices (ACS Central Science, “Self-Assembled Multifunctional Hybrids: Toward Developing High-Performance Graphene-Based Architectures for Energy Storage Devices”).

The conundrum researchers have faced in developing miniature energy storage devices, such as batteries and supercapacitors, has been figuring out how to increase the surface area of the device, to store more charge, without making it larger.

A July 27, 2015 University of Wollongong news release by Grant Reynolds, which originated the news item, describes the research in more detail,

To solve this problem, a team of PhD students, led by Dr Konstantin Konstantinov under the patronage of ISEM Director Professor Shi Xue Dou and with the support of Professor Hua Kun Liu, the head of ISEM Energy Storage Division, have developed a three-dimensional structure using a flat-pack self-assembly of three components: graphene, a conductive polymer and carbon nanotubes, which are atom-thick lattice-like networks of carbon formed into cylinders.

Graphene, made from single atom-thick layers of graphite, was a suitable candidate due its electronic performance and mechanical strength.

“We knew in theory that if you can make a sort of carbon skeleton you have a greater surface area and greater surface area means more charge,” Dr Konstantinov said. “If we could efficiently separate the layers of carbon we could then use both surfaces of each layer for charge accumulation. The problem we faced was that fabricating these 3D shapes in practice, not just theory, is a challenging, if not impossible task.”

The solution was to flat-pack the components by building the 3D shape layer-by-layer, much like a miniature exercise in cake decoration. The graphene in liquid form was mixed with the conductive polymer and reduced to solid and the carbon nanotubes carefully inserted between the graphene layers to form a self-assembled flat-packed, wafer-thin supercapacitor material.

“The real challenge was how to assemble these three components into a single structure with the best use of the space available,” PhD student Monirul Islam said. “Getting the proportions or ratios of the components appropriately in order to obtain a composite material with maximum energy storage performance was another challenge.”

Wrong proportions of either ingredient result in a lumpy mess, or a 3D shape that isn’t strong enough to retain the needed flexibility as well as the charge storage ability. There’s also elegance in the simplicity of the team’s design: the researchers dispersed the components in liquid crystalline, which enabled natural chemical interactions to prevent the graphene layers clumping together.

The result was a 3D shape with, thanks to the carbon nanotubes, a massive surface area, excellent charge capacity that is also foldable. It can also be cheaply and easily fabricated without the need for expensive vacuum chambers or sophisticated equipment.

“Our graphene-based flexible composite is highly conductive, lightweight, is able to fold like a roll or stack like a paper in electronic devices to store a huge amount of charge,” Monirul said. “This material can store charge in a second and deliver the charge in superfast speed and will be more lightweight than traditional batteries used in present day’s electronics.”

The ISEM study has been financially supported by the Automotive Australia 2020 CRC as part of its research into electric vehicles. ISEM is the program leader for electrification and plays crucial role for design of next generation electric vehicles A key to unlocking the electric vehicle’s capability is a lightweight and powerful battery pack.

“Our simple fabrication method of eco-friendly materials with increased performance has great potential to be scaled up for use supercapacitor and battery technology. Our next step is to use this material to fabricate flexible wearable supercapacitors with high power density and energy density as well as large scale supercapacitors for electric vehicles.”

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

Self-Assembled Multifunctional Hybrids: Toward Developing High-Performance Graphene-Based Architectures for Energy Storage Devices by Md. Monirul Islam, Seyed Hamed Aboutalebi, Dean Cardillo, Hua Kun Liu, Konstantin Konstantinov, and Shi Xue Dou. ACS Cent. Sci., 2015, 1 (4), pp 206–216 DOI: 10.1021/acscentsci.5b00189 Publication Date (Web): July 2, 2015

Copyright © 2015 American Chemical Society

This appears to be an open access paper.

Replacing metal with nanocellulose paper

The quest to find uses for nanocellulose materials has taken a step forward with some work coming from the University of Maryland (US). From a July 24, 2015 news item on Nanowerk,

Researchers at the University of Maryland recently discovered that paper made of cellulose fibers is tougher and stronger the smaller the fibers get … . For a long time, engineers have sought a material that is both strong (resistant to non-recoverable deformation) and tough (tolerant of damage).

“Strength and toughness are often exclusive to each other,” said Teng Li, associate professor of mechanical engineering at UMD. “For example, a stronger material tends to be brittle, like cast iron or diamond.”

A July 23, 2015 University of Maryland news release, which originated the news item, provides details about the thinking which buttresses this research along with some details about the research itself,

The UMD team pursued the development of a strong and tough material by exploring the mechanical properties of cellulose, the most abundant renewable bio-resource on Earth. Researchers made papers with several sizes of cellulose fibers – all too small for the eye to see – ranging in size from about 30 micrometers to 10 nanometers. The paper made of 10-nanometer-thick fibers was 40 times tougher and 130 times stronger than regular notebook paper, which is made of cellulose fibers a thousand times larger.

“These findings could lead to a new class of high performance engineering materials that are both strong and tough, a Holy Grail in materials design,” said Li.

High performance yet lightweight cellulose-based materials might one day replace conventional structural materials (i.e. metals) in applications where weight is important. This could lead, for example, to more energy efficient and “green” vehicles. In addition, team members say, transparent cellulose nanopaper may become feasible as a functional substrate in flexible electronics, resulting in paper electronics, printable solar cells and flexible displays that could radically change many aspects of daily life.

Cellulose fibers can easily form many hydrogen bonds. Once broken, the hydrogen bonds can reform on their own—giving the material a ‘self-healing’ quality. The UMD discovered that the smaller the cellulose fibers, the more hydrogen bonds per square area. This means paper made of very small fibers can both hold together better and re-form more quickly, which is the key for cellulose nanopaper to be both strong and tough.

“It is helpful to know why cellulose nanopaper is both strong and tough, especially when the underlying reason is also applicable to many other materials,” said Liangbing Hu, assistant professor of materials science at UMD.

To confirm, the researchers tried a similar experiment using carbon nanotubes that were similar in size to the cellulose fibers. The carbon nanotubes had much weaker bonds holding them together, so under tension they did not hold together as well. Paper made of carbon nanotubes is weak, though individually nanotubes are arguably the strongest material ever made.

One possible future direction for the research is the improvement of the mechanical performance of carbon nanotube paper.

“Paper made of a network of carbon nanotubes is much weaker than expected,” said Li. “Indeed, it has been a grand challenge to translate the superb properties of carbon nanotubes at nanoscale to macroscale. Our research findings shed light on a viable approach to addressing this challenge and achieving carbon nanotube paper that is both strong and tough.”

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

Anomalous scaling law of strength and toughness of cellulose nanopaper by Hongli Zhu, Shuze Zhu, Zheng Jia, Sepideh Parvinian, Yuanyuan Li, Oeyvind Vaaland, Liangbing Hu, and Teng Li. PNAS (Proceedings of the National Academy of Sciences) July 21, 2015 vol. 112 no. 29 doi: 10.1073/pnas.1502870112

This paper is behind a paywall.

There is a lot of research on applications for nanocellulose, everywhere it seems, except Canada, which at one time was a leader in the business of producing cellulose nanocrystals (CNC).

Here’s a sampling of some of my most recent posts on nanocellulose,

Nanocellulose as a biosensor (July 28, 2015)

Microscopy, Paper and Fibre Research Institute (Norway), and nanocellulose (July 8, 2015)

Nanocellulose markets report released (June 5, 2015; US market research)

New US platform for nanocellulose and occupational health and safety research (June 1, 2015; Note: As you find new applications, you need to concern yourself with occupational health and safety.)

‘Green’, flexible electronics with nanocellulose materials (May 26, 2015; research from China)

Treating municipal wastewater and dirty industry byproducts with nanocellulose-based filters (Dec. 23, 2014; research from Sweden)

Nanocellulose and an intensity of structural colour (June 16, 2014; research about replacing toxic pigments with structural colour from the UK)

I ask again, where are the Canadians? If anybody has an answer, please let me know.