Tag Archives: carbon nanotubes

First carbon nanotube mirrors for Cubesat telescope

A July 12, 2016 news item on phys.org describes a project that could lead to the first carbon nanotube mirrors to be used in a Cubesat telescope in space,

A lightweight telescope that a team of NASA scientists and engineers is developing specifically for CubeSat scientific investigations could become the first to carry a mirror made of carbon nanotubes in an epoxy resin.

Led by Theodor Kostiuk, a scientist at NASA’s [US National Aeronautics and Space Administration] Goddard Space Flight Center in Greenbelt, Maryland, the technology-development effort is aimed at giving the scientific community a compact, reproducible, and relatively inexpensive telescope that would fit easily inside a CubeSat. Individual CubeSats measure four inches on a side.

John Kolasinski (left), Ted Kostiuk (center), and Tilak Hewagama (right) hold mirrors made of carbon nanotubes in an epoxy resin. The mirror is being tested for potential use in a lightweight telescope specifically for CubeSat scientific investigations. Credit: NASA/W. Hrybyk

John Kolasinski (left), Ted Kostiuk (center), and Tilak Hewagama (right) hold mirrors made of carbon nanotubes in an epoxy resin. The mirror is being tested for potential use in a lightweight telescope specifically for CubeSat scientific investigations. Credit: NASA/W. Hrybyk

A July 12, 2016 US National Aeronautics and Space Administration (NASA) news release, which originated the news item, provides more information about Cubesats,

Small satellites, including CubeSats, are playing an increasingly larger role in exploration, technology demonstration, scientific research and educational investigations at NASA. These miniature satellites provide a low-cost platform for NASA missions, including planetary space exploration; Earth observations; fundamental Earth and space science; and developing precursor science instruments like cutting-edge laser communications, satellite-to-satellite communications and autonomous movement capabilities. They also allow an inexpensive means to engage students in all phases of satellite development, operation and exploitation through real-world, hands-on research and development experience on NASA-funded rideshare launch opportunities.

Under this particular R&D effort, Kostiuk’s team seeks to develop a CubeSat telescope that would be sensitive to the ultraviolet, visible, and infrared wavelength bands. It would be equipped with commercial-off-the-shelf spectrometers and imagers and would be ideal as an “exploratory tool for quick looks that could lead to larger missions,” Kostiuk explained. “We’re trying to exploit commercially available components.”

While the concept won’t get the same scientific return as say a flagship-style mission or a large, ground-based telescope, it could enable first order of scientific investigations or be flown as a constellation of similarly equipped CubeSats, added Kostiuk.

With funding from Goddard’s Internal Research and Development program, the team has created a laboratory optical bench made up of three commercially available, miniaturized spectrometers optimized for the ultraviolet, visible, and near-infrared wavelength bands. The spectrometers are connected via fiber optic cables to the focused beam of a three-inch diameter carbon-nanotube mirror. The team is using the optical bench to test the telescope’s overall design.

The news release then describes the carbon nanotube mirrors,

By all accounts, the new-fangled mirror could prove central to creating a low-cost space telescope for a range of CubeSat scientific investigations.

Unlike most telescope mirrors made of glass or aluminum, this particular optic is made of carbon nanotubes embedded in an epoxy resin. Sub-micron-size, cylindrically shaped, carbon nanotubes exhibit extraordinary strength and unique electrical properties, and are efficient conductors of heat. Owing to these unusual properties, the material is valuable to nanotechnology, electronics, optics, and other fields of materials science, and, as a consequence, are being used as additives in various structural materials.

“No one has been able to make a mirror using a carbon-nanotube resin,” said Peter Chen, a Goddard contractor and president of Lightweight Telescopes, Inc., a Columbia, Maryland-based company working with the team to create the CubeSat-compatible telescope.

“This is a unique technology currently available only at Goddard,” he continued. “The technology is too new to fly in space, and first must go through the various levels of technological advancement. But this is what my Goddard colleagues (Kostiuk, Tilak Hewagama, and John Kolasinski) are trying to accomplish through the CubeSat program.”

The use of a carbon-nanotube optic in a CubeSat telescope offers a number of advantages, said Hewagama, who contacted Chen upon learning of a NASA Small Business Innovative Research program awarded to Chen’s company to further advance the mirror technology. In addition to being lightweight, highly stable, and easily reproducible, carbon-nanotube mirrors do not require polishing — a time-consuming and often times expensive process typically required to assure a smooth, perfectly shaped mirror, said Kolasinski, an engineer and science collaborator on the project.

To make a mirror, technicians simply pour the mixture of epoxy and carbon nanotubes into a mandrel or mold fashioned to meet a particular optical prescription. They then heat the mold to to cure and harden the epoxy. Once set, the mirror then is coated with a reflective material of aluminum and silicon dioxide.

“After making a specific mandrel or mold, many tens of identical low-mass, highly uniform replicas can be produced at low cost,” Chen said. “Complete telescope assemblies can be made this way, which is the team’s main interest. For the CubeSat program, this capability will enable many spacecraft to be equipped with identical optics and different detectors for a variety of experiments. They also can be flown in swarms and constellations.”

There could be other applications for these carbon nanotube mirrors according to the news release,

A CubeSat telescope is one possible application for the optics technology, Chen added.

He believes it also would work for larger telescopes, particularly those comprised of multiple mirror segments. Eighteen hexagonal-shape mirrors, for example, form the James Webb Space Telescope’s 21-foot primary mirror and each of the twin telescopes at the Keck Observatory in Mauna Kea, Hawaii, contain 36 segments to form a 32-foot mirror.

Many of the mirror segments in these telescopes are identical and can therefore be produced using a single mandrel. This approach avoids the need to grind and polish many individual segments to the same shape and focal length, thus potentially leading to significant savings in schedule and cost.

Moreover, carbon-nanotube mirrors can be made into ‘smart optics’. To maintain a single perfect focus in the Keck telescopes, for example, each mirror segment has several externally mounted actuators that deform the mirrors into the specific shapes required at different telescope orientations.

In the case of carbon-nanotube mirrors, the actuators can be formed into the optics at the time of fabrication. This is accomplished by applying electric fields to the resin mixture before cure, which leads to the formation of carbon-nanotube chains and networks. After curing, technicians then apply power to the mirror, thereby changing the shape of the optical surface. This concept has already been proven in the laboratory.

“This technology can potentially enable very large-area technically active optics in space,” Chen said. “Applications address everything from astronomy and Earth observing to deep-space communications.”

Dexter Johnson provides some additional tidbits in his July 14, 2016 post (on his Nanoclast blog on the IEEE [Institute for Electrical and Electronics Engineers] about the Cubesat mirrors.

A carbon nanotube ‘bridge’ for nerves

Italian researchers have developed a three-dimensional carbon nanotube sponge (or bridge) that could be used in conjunction with neural explants according to a July 15, 2016 SISSA press release (also on EurekAlert), which describes the work,

A complex study, lasting several years and involving work groups with specialties in various fields, has shown that a new material (a three-dimensional sponge made of carbon nanotubes) supports the growth of nerve fibers, bridging segregated neural explants and providing a functional re-connection. The study, which was coordinated by the International School for Advanced Studies (SISSA) in Trieste, in collaboration with the University of Rome Tor Vergata and the University of Trieste, also observed biocompatibility in vivo of the material, demonstrating that implanting it into  the brain of small rodents does not cause large scars or a marked immune response.

“Under the microscope, it looks like a knotted tangle of tubes. It was initially studied by Maurizio De Crescenzi’s team at the University of Rome Tor Vergata for cleaning up spilled hydrocarbons in the sea,” explains Laura Ballerini, SISSA Professor and coordinator of the recently-published study. It was Maurizio Prato’s intuition, however, that pushed them to investigate the possibility of applying such a material to nerve tissue. The idea of developing the hybrids of neurons and nano-materials was the result of a long-term project and collaboration between Prato (University of Trieste) and Ballerini’s (SISSA) groups.

In the present study, Ballerini and her team first investigated the material’s reaction to nerve tissue in vitro. “We explanted two spinal cord segments and cultured them together but separated by 300 microns,” says Sadaf Usmani, a PhD student at the School and first author of the study. “In those conditions, without any scaffolds reconstructing the space between the two explants, we observed growth of nerve fibers which extended in a straight bundles in any direction, but not necessarily towards the other tissue. If we insert a small piece of the carbon sponge into the space between the two, however, we see dense growth of nerve fibers that fill the structure and intertwine with the other sample.”

“Observing fiber reaching the contralateral explant is not enough, however,” points out University of Trieste researcher and one of the authors of the study, Denis Scaini. “You have to show that there is a functional connection between the two populations of neurons.” For this, SISSA Professor, David Zoccolan and his team’s contribution was crucial. “With signal analysis techniques they had already developed, we were able to demonstrate two things: first, that spontaneous nervous activity in the two samples was actually correlated, indicating a connection, that was not there when the sponge was absent, and second,, that by applying an electrical signal to one of the samples, the activity of the second sample could be triggered, but only when the nanotubes were present.”

Tests for Biocompatibility

The results in the lab were extremely positive. But this was not sufficient for Ballerini and her colleagues. “In order to continue to invest additional energy and resources to the study for potential applications, is crucial to test if the material is accepted by living organisms without negative consequences,” says Ballerini.

To perform these tests, Ballerini’s team worked closely with SISSA Post-Doc researcher, and member of Zoccolan’s team, Federica Rosselli. “We implanted small portions of the material into the brain of healthy rodents. After four weeks, we observed that the material was well tolerated. There were limited scars, as well as low immune responses, some biological indicators even showed that there could be positive implications. There was also a progressive invasion of neurons within the sponge. The rats were vital and healthy during the entire four weeks,” says Usmani.

“In conclusion,” says Ballerini, “the excellent results at the structural and functional level in vitro and in vivo showed biocompatibility are encouraging us to continue this line of research. These materials could be useful for covering electrodes used for treating movement disorders like Parkinson’s because they are well accepted by tissue, while the implants being used today become less effective over time because of scar tissue. We hope this encourages other research teams with multidisciplinary expertise to expand this type of study even further.”

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

3D meshes of carbon nanotubes guide functional reconnection of segregated spinal explants by Sadaf Usmani, Emily Rose Aurand, Manuela Medelin, Alessandra Fabbro, Denis Scaini, Jummi Laishram, Federica B. Rosselli, Alessio Ansuini, Davide Zoccola1, Manuela Scarselli, Maurizio De Crescenzi, Susanna Bosi, Maurizio Prato, and Laura Ballerini. Science Advances  15 Jul 2016: Vol. 2, no. 7, e1600087 DOI: 10.1126/sciadv.1600087 Published 01 July 2016

This paper is open access.

H/t July 15, 2016 news item on phys.org.

NEC and its ‘carbon nanobrush’

Long associated with the discovery of carbon nanotubes (CNTs), NEC Corporation has announced another carbon material, carbon nanobrushes, in a July 7, 2016 news item on phys.org,

NEC Corporation today [June 30, 2016] announced the discovery of a new nano carbon material, the “carbon nanobrush,” a fibrous aggregate of single-walled carbon nanohorns. Moreover, NEC has become the first company in the world to manufacture the carbon nanobrush.

A June 30, 2016 NEC Corporation press release, which originated the news item, provides more detail (Note: This excerpt has been reformatted for clarity),

“The ‘carbon nanobrush’ is a new nano carbon material that, like existing carbon nanohorns, has high water and solvent dispersity, and high adsorptivity, including substance adsorption, but has more than 10 times the electrical conductivity than existing carbon nanohorns, an important characteristic for industrial applications,” said Dr. Sumio Iijima, Senior Research Fellow, NEC Corporation. “With these characteristics, it is anticipated that the carbon nanobrush will help to improve the basic functionality of a range of devices, including increasing the speed of sensor and actuator responses, improving the output properties of batteries and capacitors, while increasing the electrical conductivity of rubber and plastic composite materials, as well as having application in a wide range of industries.”

1. TEM images of the obtained samples

2. Tips of single-walled carbon nanohorn

3. Spherical-carbon nanohorn aggregates

Carbon nanohorns are horn-shaped (figure 2) nano carbon structures 2-5 nanometers (nm) in diameter and 40-50nm in length, which until now have been produced as radial spherical aggregates (figure 3). The newly discovered carbon nanobrush is a uniquely shaped material. It is fibrous aggregates composed of radially-assembled graphene-based single-walled nanotubules, named here as fibrous aggregates of single-walled carbon nanohorns, whose structure resembles that of a round brush (figure 1).

Features of the “carbon nanobrush” include the following:

    1. Structure
      (1)Single-walled carbon nanohorns of 2-5nm in diameter and 40-50nm in length radially gather and are connected fibrously in several micrometers.
      (2)The single-walled carbon nanohorn which is a horn-shaped nano carbon structure with a large surface area radially gather and are connected fibrously in several micrometers. So it has a large surface area per unit mass (up to 1700㎡/g).
    1. Characteristics
      (1)Dispersity
      Like carbon nanohorns, the carbon nanobrush has high dispersibility, dispersing in water and organic solvents, for example. This means that it can be easily mixed with a variety of materials, making it easy to improve its characteristics as a base material.(2)Adsorptivity
      Like spherical carbon nanohorns, the carbon nanobrush can contain various substances in the nano-sized spaces inside the tubular structure, so it can be utilized as a high-performance adsorbent. When holes are formed on the surface of the carbon nanohorns by oxidation treatments, the inner space can be used, expanding the surface area by a factor of approximately five and greatly increasing adsorptivity.

      (3)Electrical conductivity
      As carbon nanobrush is a fibrous aggregate of radially-assembled carbon nanohorns, it has more than 10 times the electrical conductivity compared with existing spherical carbon nanohorn aggregates. As a result, they are highly effective in increasing the speed of sensor and actuator responses, increasing output properties of batteries and capacitors, and increasing the electrical conductivity of rubber and plastic composite materials.

  1. Production process
    Carbon nanobrush can be produced at room temperature and under atmospheric pressure using the laser ablation method where an iron-containing carbon target (mass of carbon) is irradiated by a laser with high power density. The simple production process means that they can be produced efficiently and at a low cost when compared to the cost of other nano carbon materials.

This technology was developed in part through collaborative research with the National Institute of Advanced Industrial Science and Technology (AIST).

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

Preparation and Characterization of Newly Discovered Fibrous Aggregates of Single-Walled Carbon Nanohorns by Ryota Yuge, Fumiyuki Nihey, Kiyohiko Toyama, and Masako Yudasaka. Advanced Materials DOI: 10.1002/adma.201602022 Version of Record online: 25 MAY 2016

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

This paper is behind a paywall.

For anyone interested in a history of carbon nanotubes, there’s my June 10, 2016 posting: The birth of carbon nanotubes (CNTs): a history, which includes a mention of NEC and its position as the discoverer of carbon nanotubes.

Wireless, wearable carbon nanotube-based gas sensors for soldiers

Researchers at MIT (Massachusetts Institute of Technology) are hoping to make wireless, toxic gas detectors the size of badges. From a June 30, 2016 news item on Nanowerk,

MIT researchers have developed low-cost chemical sensors, made from chemically altered carbon nanotubes, that enable smartphones or other wireless devices to detect trace amounts of toxic gases.

Using the sensors, the researchers hope to design lightweight, inexpensive radio-frequency identification (RFID) badges to be used for personal safety and security. Such badges could be worn by soldiers on the battlefield to rapidly detect the presence of chemical weapons — such as nerve gas or choking agents — and by people who work around hazardous chemicals prone to leakage.

A June 30, 2016 MIT news release (also on EurekAlert), which originated the news item, describes the technology further,

“Soldiers have all this extra equipment that ends up weighing way too much and they can’t sustain it,” says Timothy Swager, the John D. MacArthur Professor of Chemistry and lead author on a paper describing the sensors that was published in the Journal of the American Chemical Society. “We have something that would weigh less than a credit card. And [soldiers] already have wireless technologies with them, so it’s something that can be readily integrated into a soldier’s uniform that can give them a protective capacity.”

The sensor is a circuit loaded with carbon nanotubes, which are normally highly conductive but have been wrapped in an insulating material that keeps them in a highly resistive state. When exposed to certain toxic gases, the insulating material breaks apart, and the nanotubes become significantly more conductive. This sends a signal that’s readable by a smartphone with near-field communication (NFC) technology, which allows devices to transmit data over short distances.

The sensors are sensitive enough to detect less than 10 parts per million of target toxic gases in about five seconds. “We are matching what you could do with benchtop laboratory equipment, such as gas chromatographs and spectrometers, that is far more expensive and requires skilled operators to use,” Swager says.

Moreover, the sensors each cost about a nickel to make; roughly 4 million can be made from about 1 gram of the carbon nanotube materials. “You really can’t make anything cheaper,” Swager says. “That’s a way of getting distributed sensing into many people’s hands.”

The paper’s other co-authors are from Swager’s lab: Shinsuke Ishihara, a postdoc who is also a member of the International Center for Materials Nanoarchitectonics at the National Institute for Materials Science, in Japan; and PhD students Joseph Azzarelli and Markrete Krikorian.

Wrapping nanotubes

In recent years, Swager’s lab has developed other inexpensive, wireless sensors, called chemiresistors, that have detected spoiled meat and the ripeness of fruit, among other things [go to the end of this post for links to previous posts about Swager’s work]. All are designed similarly, with carbon nanotubes that are chemically modified, so their ability to carry an electric current changes when exposed to a target chemical.

This time, the researchers designed sensors highly sensitive to “electrophilic,” or electron-loving, chemical substances, which are often toxic and used for chemical weapons.

To do so, they created a new type of metallo-supramolecular polymer, a material made of metals binding to polymer chains. The polymer acts as an insulation, wrapping around each of the sensor’s tens of thousands of single-walled carbon nanotubes, separating them and keeping them highly resistant to electricity. But electrophilic substances trigger the polymer to disassemble, allowing the carbon nanotubes to once again come together, which leads to an increase in conductivity.

In their study, the researchers drop-cast the nanotube/polymer material onto gold electrodes, and exposed the electrodes to diethyl chlorophosphate, a skin irritant and reactive simulant of nerve gas. Using a device that measures electric current, they observed a 2,000 percent increase in electrical conductivity after five seconds of exposure. Similar conductivity increases were observed for trace amounts of numerous other electrophilic substances, such as thionyl chloride (SOCl2), a reactive simulant in choking agents. Conductivity was significantly lower in response to common volatile organic compounds, and exposure to most nontarget chemicals actually increased resistivity.

Creating the polymer was a delicate balancing act but critical to the design, Swager says. As a polymer, the material needs to hold the carbon nanotubes apart. But as it disassembles, its individual monomers need to interact more weakly, letting the nanotubes regroup. “We hit this sweet spot where it only works when it’s all hooked together,” Swager says.

Resistance is readable

To build their wireless system, the researchers created an NFC tag that turns on when its electrical resistance dips below a certain threshold.

Smartphones send out short pulses of electromagnetic fields that resonate with an NFC tag at radio frequency, inducing an electric current, which relays information to the phone. But smartphones can’t resonate with tags that have a resistance higher than 1 ohm.

The researchers applied their nanotube/polymer material to the NFC tag’s antenna. When exposed to 10 parts per million of SOCl2 for five seconds, the material’s resistance dropped to the point that the smartphone could ping the tag. Basically, it’s an “on/off indicator” to determine if toxic gas is present, Swager says.

According to the researchers, such a wireless system could be used to detect leaks in Li-SOCl2 (lithium thionyl chloride) batteries, which are used in medical instruments, fire alarms, and military systems.

The next step, Swager says, is to test the sensors on live chemical agents, outside of the lab, which are more dispersed and harder to detect, especially at trace levels. In the future, there’s also hope for developing a mobile app that could make more sophisticated measurements of the signal strength of an NFC tag: Differences in the signal will mean higher or lower concentrations of a toxic gas. “But creating new cell phone apps is a little beyond us right now,” Swager says. “We’re chemists.”

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

Ultratrace Detection of Toxic Chemicals: Triggered Disassembly of Supramolecular Nanotube Wrappers by Shinsuke Ishihara, Joseph M. Azzarelli, Markrete Krikorian, and Timothy M. Swager. J. Am. Chem. Soc., Article ASAP DOI: 10.1021/jacs.6b03869 Publication Date (Web): June 23, 2016

Copyright © 2016 American Chemical Society

This paper is behind a paywall.

Here are links to other posts about Swager’s work featured here previously:

Carbon nanotubes sense spoiled food (April 23, 2015 post)

Smart suits for US soldiers—an update of sorts from the Lawrence Livermore National Laboratory (Feb. 25, 2014 post)

Come, see my etchings … they detect poison gases (Oct. 9, 2012 post)

Soldiers sniff overripe fruit (May 1, 2012 post)

The birth of carbon nanotubes (CNTs): a history

There is a comprehensive history of the carbon nanotube stretching back to prehistory and forward to recent times in a June 3, 2016 Nanowerk Spotlight article by C.K. Nisha and Yashwant Mahajan of the Center of Knowledge Management of Nanoscience & Technology (CKMNT) in India. The authors provide an introduction explaining the importance of CNTs,

Carbon nanotubes (CNTs) have been acknowledged as the material of the 21st century. They possess unique combination of extraordinary mechanical, electronic, transport, electrical and optical, properties and nanoscale sizes making them suitable for a variety of applications ranging from engineering, electronics, optoelectronics, photonics, space, defence industry, medicine, molecular and biological systems and so on and so forth. Worldwide demand for CNTs is increasing at a rapid pace as applications for the material are being matured.

According to MarketsandMarkets (M&M), the global market for carbon nanotubes in 2015 was worth about $2.26 billion1; an increase of 45% from 2009 (i.e. ~ $ 1.24 billion). This was due to the growing potential of CNTs in electronics, plastics and energy storage applications and the projected market of CNTs is expected to be around $ 5.64 billion in 2020.

In view of the scientific and technological potential of CNTs, it is of immense importance to know who should be credited for their discovery. In the present article, we have made an attempt to give a glimpse into the discovery and early history of this fascinating material for our readers. Thousands of papers are being published every year on CNTs or related areas and most of these papers give credit for the discovery of CNTs to Sumio Iijima of NEC Corporation, Japan, who, in 1991, published a ground-breaking paper in Nature reporting the discovery of multi-walled carbon nanotubes (MWCNTs)2. This paper has been cited over 27,105 times in the literature (as on January 12, 2016, based on Scopus database). This discovery by Iijima has triggered an avalanche of scientific publications and catapulted CNTs onto the global scientific stage.

Nisha and Mahajan then prepare to take us back in time,

In a guest editorial for the journal Carbon, Marc Monthioux and Vladimir L. Kuznetsov3 have tried to clear the air by describing the chronological events that led to the discovery of carbon nanotubes. As one delves deeper into the history of carbon nanotubes, it becomes more apparent that the origin of CNTs could be even pre-historic in nature.

Recently, Ponomarchuk et al from Russia have reported the presence micro and nano carbon tubes in igneous rocks formed about 250 million years ago4-7. They suggested the possibility of formation of carbon nanotubes during the magmatic processes. It is presumed that the migration of hydrocarbon fluids through the residual melt of the rock groundmass created gas-saturated areas (mostly CH4, CO2, CO) in which condensation and decomposition of hydrocarbon in presence of metal elements resulted in the formation of micro and sub-micron carbon tubes.

Another most compelling evidence of pre-historic naturally occurring carbon nanotubes (MWCNTs) is based on the TEM studies carried out by Esquivel and Murr8 that analyzed 10,000-year-old Greenland ice core samples and it was suggested that probably they could have been formed during combustion of natural gas/methane during natural processes.

However, the validity of this evidence is questionable owing to the lack of clear high-resolution TEM images, high-quality diffraction patterns or Raman spectroscopy data. In addition, [an]other interesting possibility is that the carbon nanotubes could have been directly formed by the transformation of naturally occurring C60 fullerenes in nature without the assistance of man, given the right conditions prevail. Suchanek et al.,9 have actually demonstrated this thesis, under the laboratory environment, by transforming C60 fullerenes into CNTs under hydrothermal conditions.

There is a large body of evidence in literature about the existence of naturally occurring fullerenes in nature, e.g., coal, carboneous rocks, interstellar media, etc. Since the above experiments were conducted under the simulated geological environment, their results imply that CNTs may form in natural hydrothermal environment.

This hypothesis was further corroborated by Velasco-Santos and co-workers10, when they reported the presence of CNTs in a coal–petroleum mix obtained from an actual oil well, identified by the PEMEX (the Mexican Petroleum Company) as P1, which is located in Mexico’s southeast shore. TEM studies revealed that the coal-petroleum mix contained predominantly end-capped CNTs that are nearly 2 µm long with outer diameter varying between few to several tenths of nanometers.

There’s another study supporting the notion that carbon nanotubes may be formed naturally,

In yet another study, researchers from Germany11 have synthesized carbon nanotubes using igneous rock from Mount Etna lava as both support and catalyst. The naturally occurring iron oxide particles present in Etna lava rock make it an ideal material for growing and immobilizing nanocarbons.

When a mixture of ethylene and hydrogen were passed over the pulverized rocks reduced in a hydrogen atmosphere at 700°C, the iron particles catalyzed the decomposition of ethylene to elemental carbon, which gets deposited on the lava rock in the form of tiny tubes and fibers.
This study showed that if a carbon source is available, CNTs/CNFs can grow on a mineral at moderate temperatures, which directs towards the possibilities of carbon nanotube formation in active suboceanic volcanos or even in interstellar space where methane, atomic hydrogen, carbon oxides, and metallic iron are present.

This fascinating and informative piece was originally published in the January 2016 edition of Nanotech Insights (CKMNT newsletter; scroll down) and can be found there although it may be more easily accessible as the June 3, 2016 Nanowerk Spotlight article where it extends over five (Nanowerk) pages and has a number of embedded images along with an extensive list of references at the end.

Enjoy!

New model to track flow of nanomaterials through our air, earth, and water

Just how many tons of nanoparticles are making their way through the environment? Scientists at the Swiss Federal Laboratories for Materials Science and Technology (Empa) have devised a new model which could help answer that question. From a May 12, 2016 news item on phys.org,

Carbon nanotubes remain attached to materials for years while titanium dioxide and nanozinc are rapidly washed out of cosmetics and accumulate in the ground. Within the National Research Program “Opportunities and Risks of Nanomaterials” (NRP 64) a team led by Empa scientist Bernd Nowack has developed a new model to track the flow of the most important nanomaterials in the environment.

A May 12, 2016 Empa press release by Michael Hagmann, which also originated the news item, provides more detail such as an estimated tonnage for titanium dioxide nanoparticles produced annually in Europe,

How many man-made nanoparticles make their way into the air, earth or water? In order to assess these amounts, a group of researchers led by Bernd Nowack from Empa, the Swiss Federal Laboratories for Materials Science and Technology, has developed a computer model as part of the National Research Program “Opportunities and Risks of Nanomaterials” (NRP 64). “Our estimates offer the best available data at present about the environmental accumulation of nanosilver, nanozinc, nano-tinanium dioxide and carbon nanotubes”, says Nowack.

In contrast to the static calculations hitherto in use, their new, dynamic model does not just take into account the significant growth in the production and use of nanomaterials, but also makes provision for the fact that different nanomaterials are used in different applications. For example, nanozinc and nano-titanium dioxide are found primarily in cosmetics. Roughly half of these nanoparticles find their way into our waste water within the space of a year, and from there they enter into sewage sludge. Carbon nanotubes, however, are integrated into composite materials and are bound in products such as which are immobilized and are thus found for example in tennis racquets and bicycle frames. It can take over ten years before they are released, when these products end up in waste incineration or are recycled.

39,000 metric tons of nanoparticles

The researchers involved in this study come from Empa, ETH Zurich and the University of Zurich. They use an estimated annual production of nano-titanium dioxide across Europe of 39,000 metric tons – considerably more than the total for all other nanomaterials. Their model calculates how much of this enters the atmosphere, surface waters, sediments and the earth, and accumulates there. In the EU, the use of sewage sludge as fertilizer (a practice forbidden in Switzerland) means that nano-titanium dioxide today reaches an average concentration of 61 micrograms per kilo in affected soils.

Knowing the degree of accumulation in the environment is only the first step in the risk assessment of nanomaterials, however. Now this data has to be compared with results of eco-toxicological tests and the statutory thresholds, says Nowack. A risk assessment has not been carried out with his new model so far. Earlier work with data from a static model showed, however, that the concentrations determined for all four nanomaterials investigated are not expected to have any impact on the environment.

But in the case of nanozinc at least, its concentration in the environment is approaching the critical level. This is why this particular nanomaterial has to be given priority in future eco-toxicological studies – even though nanozinc is produced in smaller quantities than nano-titanium dioxide. Furthermore, eco-toxicological tests have until now been carried out primarily with freshwater organisms. The researchers conclude that additional investigations using soil-dwelling organisms are a priority.

Here are links to and citations for papers featuring the work,

Dynamic Probabilistic Modeling of Environmental Emissions of Engineered Nanomaterials by Tian Yin Sun†, Nikolaus A. Bornhöft, Konrad Hungerbühler, and Bernd Nowack. Environ. Sci. Technol., 2016, 50 (9), pp 4701–4711 DOI: 10.1021/acs.est.5b05828 Publication Date (Web): April 04, 2016

Copyright © 2016 American Chemical Society

Probabilistic environmental risk assessment of five nanomaterials (nano-TiO2, nano-Ag, nano-ZnO, CNT, and fullerenes) by Claudia Coll, Dominic Notter, Fadri Gottschalk, Tianyin Sun, Claudia Som, & Bernd Nowack. Nanotoxicology Volume 10, Issue 4, 2016 pages 436-444 DOI: 10.3109/17435390.2015.1073812 Published online: 10 Nov 2015

The first paper, which is listed in Environmental Science & Technology, appears to be open access while the second paper is behind a paywall.

Teslaphoresis; self-assembling materials from a distance

Getting carbon nanotubes to self-assemble from a distance is possible according to an April 14, 2016 news item on ScienceDaily,

Scientists at Rice University have discovered that the strong force field emitted by a Tesla coil causes carbon nanotubes to self-assemble into long wires, a phenomenon they call “Teslaphoresis.”

An April 14, 2016 Rice University (US) news release, (also on EurekAlert) which originated the news item, expands on the theme,

Cherukuri [Rice chemist Paul Cherukuri] sees this research as setting a clear path toward scalable assembly of nanotubes from the bottom up.

The system works by remotely oscillating positive and negative charges in each nanotube, causing them to chain together into long wires. Cherukuri’s specially designed Tesla coil even generates a tractor beam-like effect as nanotube wires are pulled toward the coil over long distances.

This force-field effect on matter had never been observed on such a large scale, Cherukuri said, and the phenomenon was unknown to Nikola Tesla, who invented the coil in 1891 with the intention of delivering wireless electrical energy.

“Electric fields have been used to move small objects, but only over ultrashort distances,” Cherukuri said. “With Teslaphoresis, we have the ability to massively scale up force fields to move matter remotely.”

The researchers discovered that the phenomenon simultaneously assembles and powers circuits that harvest energy from the field. In one experiment, nanotubes assembled themselves into wires, formed a circuit connecting two LEDs and then absorbed energy from the Tesla coil’s field to light them.

Cherukuri realized a redesigned Tesla coil could create a powerful force field at distances far greater than anyone imagined. His team observed alignment and movement of the nanotubes several feet away from the coil. “It is such a stunning thing to watch these nanotubes come alive and stitch themselves into wires on the other side of the room,” he said.

Nanotubes were a natural first test material, given their heritage at Rice, where the HiPco production process was invented. But the researchers envision many other nanomaterials can be assembled as well.

Lindsey Bornhoeft, the paper’s lead author and a biomedical engineering graduate student at Texas A&M University, said the directed force field from the bench-top coil at Rice is restricted to just a few feet. To examine the effects on matter at greater distances would require larger systems that are under development. Cherukuri suggested patterned surfaces and multiple Tesla coil systems could create more complex self-assembling circuits from nanoscale-sized particles.

Cherukuri and his wife, Tonya, also a Rice alum and a co-author of the paper, noted that their son Adam made some remarkable observations while watching videos of the experiment. “I was surprised that he noticed patterns in nanotube movements that I didn’t see,” Cherukuri said. “I couldn’t make him an author on the paper, but both he and his little brother John are acknowledged for helpful discussions.”

Cherukuri knows the value of youthful observation — and imagination — since he started designing Tesla coils as a teen. “I would have never thought, as a 14-year-old kid building coils, that it was going to be useful someday,” he said.

Cherukuri and his team self-funded the work, which he said made it more meaningful for the group. “This was one of the most exciting projects I’ve ever done, made even more so because it was an all-volunteer group of passionate scientists and students. But because Rice has this wonderful culture of unconventional wisdom, we were able to make an amazing discovery that pushes the frontiers of nanoscience.”

The teammates look forward to seeing where their research leads. “These nanotube wires grow and act like nerves, and controlled assembly of nanomaterials from the bottom up may be used as a template for applications in regenerative medicine,” Bornhoeft said.

“There are so many applications where one could utilize strong force fields to control the behavior of matter in both biological and artificial systems,” Cherukuri said. “And even more exciting is how much fundamental physics and chemistry we are discovering as we move along. This really is just the first act in an amazing story.”

Rice University has produced a video featuring the research and the researchers,

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

Teslaphoresis of Carbon Nanotubes by Lindsey R. Bornhoeft, Aida C. Castillo, Preston R. Smalley, Carter Kittrell, Dustin K. James, Bruce E. Brinson, Thomas R. Rybolt, Bruce R. Johnson, Tonya K. Cherukuri†, and Paul Cherukuri. ACS Nano, Article ASAP DOI: 10.1021/acsnano.6b02313 Publication Date (Web): April 13, 2016

Copyright © 2016 American Chemical Society

This paper is behind a paywall.

The Tesla coil was created by Nikola Tesla, a renowned Serbian-American scientist and engineer.

Doped carbon nanotubes and a new path to quantum encryption

An April 12, 2016 news item on ScienceDaily describes a use for  carbon nanotubes in the field of quantum encryption,

Critical information, ranging from credit card numbers to national security data, is sent in streams of light, or laser pulses. However, the data transmitted in this manner can be stolen by splitting out a few photons (packets of light) from the laser pulse. Such eavesdropping could be prevented by encoding the data into single photons. But that requires generating single photons. Researchers demonstrated a new material, made from tiny carbon tubes, that emits the desired photons at room temperature.

A March 31, 2016 US Department of Energy news release, which originated the news item, explains the concept in more detail,

Digital eavesdropping could be prevented by encoding bits of information in the properties, or quantum mechanical states, of single photons. Single photons emitted by carbon nanotubes altered, or doped with oxygen, are especially attractive for realizing this quantum information technology.

Summary

Single photon generation requires an isolated, quantum mechanical, two-level system that can emit only one photon in one excitation-emission cycle. While artificial nanoscale materials (such as quantum dots and vacancy centers in diamonds) have been explored for single photon generation, none have emerged as the ideal candidate that meets all of the technological requirements. These requirements include the ability to generate single photons in the 1.3 to 1.5 µm fiber optic telecommunication wavelength range at room temperature. Earlier studies revealed that carbon nanotubes were not suited for use in quantum communications because the tubes required extremely low temperatures and had strong photoluminescence fluctuations. In contrast to these earlier findings, researchers led by Han Htoon and Stephen Doorn of the Center for Integrated Nanotechnologies showed that oxygen doping of carbon nanotubes can lead to fluctuation-free photoluminescence emission in the telecommunication wavelength range. Experiments measuring the time-distribution of two successive photon emission events also unambiguously demonstrated single photon emission at room temperature. Furthermore, because oxygen doping is achieved through a simple deposition of a silicon dioxide layer, these doped carbon nanotubes are fully compatible with silicon microfabrication technology and can be fabricated into electrically driven single photon sources. In addition, the silicon dioxide layer encapsulating the nanotubes allows for their easy integration into electronic and photonic integrated circuits. Beyond the implementation of this new method into quantum communication technologies, nanotube-based single photon sources could enable other transformative quantum technologies, including ultra-sensitive absorption measurements, sub-diffraction imaging, and linear quantum computing.

The researchers have provided an illustration of doped carbon nanotubes,

The deposition of a silicon dioxide layer (yellow layer) on a carbon nanotube (gray spheres) introduces solitary oxygen dopants (red spheres). A single photon (red and white star) is emitted when a dopant is excited by a laser pulse (green arrow). Image courtesy of the Center for Integrated Nanotechnologies

The deposition of a silicon dioxide layer (yellow layer) on a carbon nanotube (gray spheres) introduces solitary oxygen dopants (red spheres). A single photon (red and white star) is emitted when a dopant is excited by a laser pulse (green arrow). Image courtesy of the Center for Integrated Nanotechnologies

Here’s a link to and a citation for the paper, which was published a surprisingly long time ago,

Room-temperature single-photon generation from solitary dopants of carbon nanotubes by Xuedan Ma, Nicolai F. Hartmann, Jon K. S. Baldwin, Stephen K. Doorn, & Han Htoon.  Nature Nanotechnology 10, 671–675 (2015)  doi:10.1038/nnano.2015.136 Published online 13 July 2015

This paper is behind a paywall.

The Canadian nano scene as seen by the OECD (Organization for Economic Cooperation and Development)

I’ve grumbled more than once or twice about the seemingly secret society that is Canada’s nanotechnology effort (especially health, safety, and environment issues) and the fact that I get most my information from Organization for Economic Cooperation and Development (OECD) documents. That said, thank you to Lynne Bergeson’s April 8, 2016 post on Nanotechnology Now for directions to the latest OECD nano document,

The Organization for Economic Cooperation and Development recently posted a March 29, 2016, report entitled Developments in Delegations on the Safety of Manufactured Nanomaterials — Tour de Table. … The report compiles information, provided by Working Party on Manufactured Nanomaterials (WPMN) participating delegations, before and after the November 2015 WPMN meeting, on current developments on the safety of manufactured nanomaterials.

It’s an international roundup that includes: Australia, Austria, Belgium, Canada, Germany, Japan, Korea, the Netherlands, Switzerland, Turkey, United Kingdom, U.S., and the European Commission (EC), as well as the Business and Industry Advisory Committee to the OECD (BIAC) and International Council on Animal Protection in OECD Programs (ICAPO).

As usual, I’m focusing on Canada. From the DEVELOPMENTS IN DELEGATIONS ON THE SAFETY OF MANUFACTURED NANOMATERIALS – TOUR DE TABLE Series on the Safety of Manufactured Nanomaterials No. 67,

CANADA
National  developments  on  human  health  and  environmental  safety  including  recommendations, definitions, or discussions related to adapting or applying existing regulatory systems or the drafting of new laws/ regulations/amendments/guidance materials A consultation document on a Proposed Approach to Address Nanoscale Forms of Substances on the Domestic  Substances  List was  published  with  a  public  comment  period  ending on  May  17,  2015. The proposed approach outlines the Government’s plan to address nanomaterials considered in commerce in Canada (on  Canada’s  public inventory).  The  proposal is a stepwise  approach to  acquire  and  evaluate information,  followed  by  any  necessary  action. A  follow-up  stakeholder  workshop  is  being  planned  to discuss  next  steps  and  possible  approaches  to prioritize  future  activities. The  consultation document  is available at: http://www.ec.gc.ca/lcpe-cepa/default.asp?lang=En&n=1D804F45-1

A mandatory information gathering survey was published on July 25, 2015. The purpose of the survey is to collect information to determine the commercialstatus of certain nanomaterials in Canada. The survey targets  206  substances  considered  to  be  potentially  in commerce  at  the  nanoscale. The  list  of  206 substances was developed using outcomes from the Canada-United States Regulatory Cooperation Council (RCC)  Nanotechnology  Initiative  to  identify nanomaterial  types. These  nanomaterial  types  were  cross-referenced  with  the Domestic  Substances  List to  develop  a  preliminary  list  of  substances  which are potentially intentionally manufactured at the nanoscale. The focus of the survey aligns with the Proposed Approach to  Address  Nanoscale  Forms  of  Substances  on  the Domestic  Substances  List (see  above)  and certain  types  of  nanomaterials  were  excluded  during the  development  of  the  list  of  substances. The information  being  requested  by  the  survey  includes substance  identification,  volumes,  and  uses.  This information will feed into the Government’s proposed approach to address nanomaterials on the Domestic Substances List. Available at: http://gazette.gc.ca/rp-pr/p1/2015/2015-07-25/html/notice-avis-eng.php

Information on:

a.risk  assessment  decisions, including  the  type  of:  (a)  nanomaterials  assessed; (b) testing recommended; and (c) outcomes of the assessment;

Four substances were notified to the program since the WPMN14 – three surface modified substances and  one  inorganic  substance.  No  actions,  including  additional  data requests,  were  taken  due  to  low expected  exposures  in  accordance  with  the New  Substances  Notifications  Regulations  (Chemicals and Polymers) (NSNR) for two of the substances.  Two of the substances notified were subject to a Significant New Activity Notice. A Significant New Activity notice is an information gathering tool used to require submission  of  additional  information  if  it  is suspected  that  a  significant  new  activity  may  result in  the substance becoming toxic under the Canadian Environmental Protection Act, 1999.

b.Proposals, or modifications to previous regulatory decisions

As  part  of  the  Government’s  Chemicals  Management Plan,  a  review  is  being  undertaken  for  all substances  which  have  been  controlled through  Significant  New  Activity  (SNAc)  notices (see  above).  As part  of  this  activity,  the  Government  is  reviewing past  nanomaterials  SNAc  notices  to  see  if  new information  is  available  to  refine  the  scope  and information  requirements.    As  a  result  of  this  review, 9 SNAc  notices  previously  in  place  for  nanomaterials have  been  rescinded.    This  work  is  ongoing,  and  a complete review of all nanomaterial SNAcs is currently planned to be completed in 2016.

Information related to good practice documents

The Canada-led,  ISO  standards project, ISO/DTR  19716 Nanotechnologies — Characterization  of cellulose  nanocrystals, [emphasis mine] initiated  in  April 2014, is  now at Committee  Draft  (CD)  3-month  ISO ballot, closing    Aug 31, 2015. Ballot comments will be addressed during JWG2 Measurement and Characterization working  group meetings  at  the 18th Plenary  of  ISO/TC229, Nanotechnologies,  being held in Edmonton, Alberta, Sep. 28 – Oct. 2, 2015.

Research   programmes   or   strategies   designed   to  address   human   health   and/   or environmental safety aspects of nanomaterials

Scientific research

Environment Canada continues to support various academic and departmental research projects. This research has to date included studying fate and effects of nanomaterials in the aquatic, sediment, soil, and air  compartments. Funding  in  fiscal  2015-16  continues  to  support  such  projects,  including  sub-surface transportation, determining key physical-chemical parameters to predict ecotoxicity, and impacts of nano-silver [silver nanoparticles]  addition  to  a  whole  lake  ecosystem [Experimental Lakes Area?]. Environment  Canada  has  also  partnered  with  the National Research  Council  of  Canada  recently  to  initiate  a project  on  the  development  of  test  methods  to identify surfaces of nanomaterials for the purposes of regulatory identification and to support risk assessments. In addition,  Environment  Canada  is  working  with  academic laboratories in  Canada  and  Germany  to  prepare guidance to support testing of nanoparticles using the OECD Test Guideline for soil column leaching.

Health  Canada  continues  its  research  efforts  to  investigate  the  effects  of  surface-modified  silica nanoparticles. The   aims   of   these   projects   are  to:   (1) study the importance of size and surface functionalization;  and  (2)  provide a genotoxic profile and  to  identify  mechanistic  relationships  of  particle properties  to  elicited  toxic  responses.  A manuscript reporting  the in  vitro genotoxic,  cytotoxic and transcriptomic  responses  following  exposure  to  silica  nanoparticles  has  recently  been  submitted to  a  peer reviewed journal and is currently undergoing review. Additional manuscripts reporting the toxicity results obtained to date are in preparation.

Information on public/stakeholder consultations;

A consultation document on a Proposed Approach to Address Nanoscale Forms of Substances on the Domestic  Substances  List was  published  with a  public  comment  period ending  on May  17,  2015  (see Question  1).  Comments  were  received  from approximately  20  stakeholders  representing  industry and industry  associations,  as  well  as  non-governmental  organizations. These  comments  will  inform  decision making to address nanomaterials in commerce in Canada.

Information on research or strategies on life cycle aspects of nanomaterials

Canada, along with Government agencies in the United States, Non-Governmental Organizations and Industry,  is  engaged  in  a  project  to  look  at releases  of  nanomaterials  from  industrial  consumer  matrices (e.g., coatings). The objectives of the NanoRelease Consumer Products project are to develop protocols or
methods (validated  through  interlaboratory  testing) to  measure  releases  of  nanomaterials  from  solid matrices as a result of expected uses along the material life cycle for consumer products that contain the nanomaterials. The  project  is  currently  in  the  advanced  stages  of Phase  3  (Interlaboratory  Studies).  The objectives of Phase 3 of the project are to develop robust methods for producing and collecting samples of CNT-epoxy  and  CNT-rubber  materials  under  abrasion  and  weathering scenarios,  and  to  detect  and quantify, to the extent possible, CNT release fractions. Selected laboratories in the US, Canada, Korea and the European Community are finalising the generation and analysis of sanding and weathering samples and the    results    are    being    collected    in    a   data    hub    for    further    interpretation    and    analysis.

Additional details about the project can be found at the project website: http://www.ilsi.org/ResearchFoundation/RSIA/Pages/NanoRelease1.aspx

Under the OECD Working Party on Resource Productivity and Waste (WPRPW), the expert group on waste containing nanomaterials has developed four reflection papers on the fate of nanomaterials in waste treatment  operations.  Canada  prepared the  paper  on  the  fate  of  nanomaterials in  landfills;  Switzerland on the  recycling  of  waste  containing  nanomaterials;  Germany  on  the  incineration  of  waste  containing nanomaterials;  and  France  on  nanomaterials  in wastewater  treatment.  The  purpose  of  these  papers is to provide  an  overview  of  the  existing  knowledge  on the  behaviour  of  nanomaterials  during  disposal operations and identify the information gaps. At the fourth meeting of the WPRPW that took place on 12-14 November 2013, three of the four reflection papers were considered by members. Canada’s paper was presented and discussed at the fifth meeting of the WPRPRW that took place on 8-10 December 2014. The four  papers  were  declassified  by  EPOC  in  June  2015, and  an  introductory  chapter  was  prepared  to  draw these  papers  together. The introductory  chapter  and accompanying  papers  will  be  published in  Fall  2015. At  the sixth  meeting  of  the  WPRPW  in  June – July  2015,  the  Secretariat  presented  a  proposal  for an information-sharing  platform  that  would  allow  delegates  to  share research  and  documents  related  to nanomaterials. During a trial phase, delegates will be asked to use the platform and provide feedback on its use at the next meeting of the WPRPW in December 2015. This information-sharing platform will also be accessible to delegates of the WPMN.

Information related to exposure measurement and exposure mitigation.

Canada and the Netherlands are co-leading a project on metal impurities in carbon nanotubes. A final version  of  the  report  is  expected  to  be ready for WPMN16. All  research has  been completed (e.g. all components are published or in press and there was a presentation by Pat Rasmussen to SG-08 at the Face-to-Face Meeting in Seoul June 2015). The first draft will be submitted to the SG-08 secretariat in autumn 2015. Revisions  will  be  based  on  early  feedback  from  SG-08  participants.  The  next  steps  depend  on  this feedback and amount of revision required.

Information on past, current or future activities on nanotechnologies that are being done in co-operation with non-OECD countries.

A webinar between ECHA [European Chemicals Agency], the US EPA [Environmental Protection Agency] and Canada was hosted by Canada on April 16, 2015. These are  regularly  scheduled  trilateral  discussions  to keep  each  other  informed  of  activities  in  respective jurisdictions.

In  March 2015, Health  Canada  hosted  3  nanotechnology knowledge  transfer sessions  targeting Canadian  government  research  and  regulatory  communities  working  in  nanotechnology.  These  sessions were  an  opportunity  to  share  information  and perspectives  on  the  current  state  of  science supporting  the regulatory  oversight  of  nanomaterials with  Government.  Presenters  provided  detailed  outputs  from  the OECD WPMN including: updates on OECD test methods and guidance documents; overviews of physical-chemical properties, as well as their relevance to toxicological testing and risk assessment; ecotoxicity and fate   test   methods;   human   health   risk   assessment   and   alternative   testing   strategies;   and exposure measurement  and  mitigation.  Guest  speakers  included  Dr  Richard  C.  Pleus  Managing  Director  and  Director of Intertox, Inc and Dr. Vladimir Murashov Special Assistant on Nanotechnology to the Director of National Institute for Occupational Safety and Health (NIOSH).

On   March   4-5, 2015, Industry   Canada   and   NanoCanada co-sponsored  “Commercializing Nanotechnology  in  Canada”,  a  national  workshop  that brought  together  representatives  from  industry, academia and government to better align Canada’s efforts in nanotechnology.  This workshop was the first of  its  kind  in  Canada. It  also  marked  the  official  launch  of  NanoCanada (http://nanocanada.com/),  a national  initiative  that  is  bringing  together stakeholders  from  across  Canada  to  bridge  the  innovation  gap and stimulates emerging technology solutions.

It’s nice to get an update about what’s going on. Despite the fact this report was published in 2016 the future tense is used in many of the verbs depicting actions long since accomplished. Maybe this was a cut-and-paste job?

Moving on, I note the mention of the Canada-led,  ISO  standards project, ISO/DTR  19716 Nanotechnologies — Characterization  of cellulose  nanocrystals (CNC). For those not familiar with CNC, the Canadian government has invested hugely in this material derived mainly from trees, in Canada. Other countries and jurisdictions have researched nanocellulose derived from carrots, bananas, pineapples, etc.

Finally, it was interesting to find out about the existence of  NanoCanada. In looking up the Contact Us page, I noticed Marie D’Iorio’s name. D’Iorio, as far as I’m aware, is still the Executive Director for Canada’s National Institute of Nanotechnology (NINT) or here (one of the National Research Council of Canada’s institutes). I have tried many times to interview someone from the NINT (Nils Petersen, the first NINT ED and Martha Piper, a member of the advisory board) and more recently D’Iorio herself only to be be met with a resounding silence. However, there’s a new government in place, so I will try again to find out more about the NINT, and, this time, NanoCanada.

Unraveling carbyne (one-dimensional carbon)

An international group of researchers has developed a technique for producing a record-breaking length of one-dimensional carbon (carbon chain) according to an April 4, 2016 news item on Nanowerk,

Elemental carbon appears in many different modifications, including diamond, fullerenes and graphene. Their unique structural, electronic, mechanical, transport and optical properties have a broad range of applications in physics, chemistry and materials science, including composite materials, nanoscale light emitting devices and energy harvesting materials. Within the “carbon family”, only carbyne, the truly one-dimensional form of carbon, has not yet been synthesized despite having been studied for more than 50 years. Its extreme instability in ambient conditions rendered the final experimental proof of its existence elusive.

An international collaboration of researchers now succeeded in developing a novel route for the bulk production of carbon chains composed of more than 6,400 carbon atoms by using thin double-walled carbon nanotubes as protective hosts for the chains.

An April 4, 2016 University of Vienna press release (also on EurekAlert) provides another perspective on the research,

Even in its elemental form, the high bond versatility of carbon allows for many different well-known materials, including diamond and graphite. A single layer of graphite, termed graphene, can then be rolled or folded into carbon nanotubes or fullerenes, respectively. To date, Nobel prizes have been awarded for both graphene (2010) and fullerenes (1996). Although the existence of carbyne, an infinitely long carbon chain, was proposed in 1885 by Adolf von Baeyer (Nobel laureate for his overall contributions in organic chemistry, 1905), scientists have not yet been able to synthesize this material. Von Baeyer even suggested that carbyne would remain elusive as its high reactivity would always lead to its immediate destruction. Nevertheless, carbon chains of increasing length have been successfully synthesized over the last 50 years, with a record of around 100 carbon atoms (2003). This record has now been broken by more than one order of magnitude, with the demonstration of micrometer length-scale chains.

The new record

Researchers from the University of Vienna, led by Thomas Pichler, have presented a novel approach to grow and stabilize carbon chains with a record length of 6,000 carbon atoms, improving the previous record by more than one order of magnitude. They use the confined space inside a double-walled carbon nanotube as a nano-reactor to grow ultra-long carbon chains on a bulk scale. In collaboration with the groups of Kazu Suenaga at the AIST Tsukuba [National Institute of Advanced Industrial Science and Technology] in Japan, Lukas Novotny at the ETH Zürich [Swiss Federal Institute of Technology] in Switzerland and Angel Rubio at the MPI [Max Planck Institute] Hamburg in Germany and UPV/EHU [University of the Basque Country] San Sebastian in Spain, the existence of the chains has been unambiguously confirmed by using a multitude of sophisticated, complementary methods. These are temperature dependent near- and far-field Raman spectroscopy with different lasers (for the investigation of electronic and vibrational properties), high resolution transmission electron spectroscopy (for the direct observation of carbyne inside the carbon nanotubes) and x-ray scattering (for the confirmation of bulk chain growth).

The researchers present their study in the latest edition of Nature Materials. “The direct experimental proof of confined ultra-long linear carbon chains, which are more than an order of magnitude longer than the longest proven chains so far, can be seen as a promising step towards the final goal of unraveling the “holy grail” of carbon allotropes, carbyne”, explains the lead author, Lei Shi.

Application potential

Carbyne is very stable inside double-walled carbon nanotubes. This property is crucial for its eventual application in future materials and devices. According to theoretical models, carbyne’s mechanical properties exceed all known materials, outperforming both graphene and diamond. Carbyne’s electrical properties suggest novel nanoelectronic applications in quantum spin transport and magnetic semiconductors.

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

Confined linear carbon chains as a route to bulk carbyne by Lei Shi, Philip Rohringer, Kazu Suenaga, Yoshiko Niimi, Jani Kotakoski, Jannik C. Meyer, Herwig Peterlik, Marius Wanko, Seymur Cahangirov, Angel Rubio, Zachary J. Lapin, Lukas Novotny, Paola Ayala, & Thomas Pichler. Nature Materials (2016) doi:10.1038/nmat4617 Published online 04 April 2016

This paper is behind a paywall.

But, there is this earlier and open access version on arXiv.org,

Confined linear carbon chains: A route to bulk carbyne
Lei Shi, Philip Rohringer, Kazu Suenaga, Yoshiko Niimi, Jani Kotakoski, Jannik C. Meyer, Herwig Peterlik, Paola Ayala, Thomas Pichler (Submitted on 17 Jul 2015 (v1), last revised 20 Jul 2015 (this version, v2))