Tag Archives: fullerenes

Water cages made of buckyballs could affect nuclear magnetic resonance and magnetic resonance imaging (MRI)

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I wasn’t expecting to find this May 20, 2014 news item on Nanowerk to be* quite so fascinating, especially as It gets off to a slow start (a link has been removed),

In a new paper in The Journal of Chemical Physics (“Nuclear spin conversion of water inside fullerene cages detected by low-temperature nuclear magnetic resonance”), produced by AIP Publishing, a research team in the United Kingdom and the United States describes how water molecules “caged” in fullerene spheres (“buckyballs”) are providing a deeper insight into spin isomers — varieties of a molecule that differ in their nuclear spin. The results of this work may one day help enhance the analytical and diagnostic power of nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI).

A May 20, 2014 American Institute of Physics (AIP) news release on EurekAlert, which originated the news item, provides some information about water molecules prior to describing the research in more detail,

Water molecules can exist as one of two isomers depending on how the spins of their two hydrogen atoms are oriented: ortho, where the spins are parallel and have a spin number of 1, and para, where the spins are antiparallel and have a spin number of 0. Scientists believe that any given molecule can transform from ortho- into para- spin states and vice versa, a process known as nuclear spin conversion.

“Currently, mechanisms for this conversion are not completely understood, nor how long it takes the molecules to transform from one spin isomer to the other,” said Salvatore Mamone, a post-doctoral physicist at the University of Southampton and lead author on the JCP paper. “To study this, we had to figure out how to reduce the strong intermolecular interactions that are responsible for aggregation and lower the rotational mobility of the water molecules.”

Next, there’s a brief summarized version of the research (from the news release),

The answer was to use chemical reactions to open a hole in fullerene (C60, also known as a buckyball) spheres, inject water molecules and then close the “cages” to form a complex referred to as H2O@C60. “At the end of this synthetic preparation nicknamed ‘molecular surgery,’ we find that 70 to 90 percent of the cages are filled, giving us a significant quantity of water molecules to examine,” Mamone said. “Because the [water] molecules are kept separated by the cages, there is a large rotational freedom that makes observation of the ortho and para isomers possible.”

This is followed by more technical details,

In their experiment, the researchers quickly cooled the individual H2O@C60 samples from 50 Kelvin (minus 223 degrees Celsius) to 5 K (minus 268 degrees Celsius) and then monitored their NMR signal every few minutes over several days.

“As the observed NMR signal is proportional to the amount of ortho-water in the sample [para-water with its spin number of 0 is “NMR silent”], we can track the percentages of ortho and para isomers at any time and any temperature,” Mamone explained. “At 50 K, we find that 75 percent of the water molecules are ortho, while at 5 K, they become almost 100 percent para. Therefore, we know that after the quick temperature jump, equilibrium is restored by conversion from ortho to para—and we see that conversion in real time.”

A surprising outcome of the experiment was that the researchers observed a second-order rate law in the kinetics of the spin conversion which proves that pairs of molecules have to interact for conversion to occur. “Previous studies have speculated that other nuclear spins can cause conversion but we found this not to be the case for H2O@C60,” Mamone said.

Next up, the research team plans to study the roles of isomer concentrations and temperature in the conversion process, the conversion of para-water to ortho (“back conversion”), how to detect single ortho- and para-water molecules on surfaces, and spin isomers in other fullerene-caged molecules.

Bravo to the news release writer for a very nice explanation of the science!

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

Nuclear spin conversion of water inside fullerene cages detected by low-temperature nuclear magnetic resonance by Salvatore Mamone, Maria Concistré, Elisa Carignani, Benno Meier, Andrea Krachmalnicoff, Ole G. Johannessen, Xuegong Lei, Yongjun Li, Mark Denning, Marina Carravetta, Kelvin Goh, Anthony J. Horsewill, Richard J. Whitby and Malcolm H. Levitt.  J. Chem. Phys. 140, 194306 (2014) DOI: 10.1063/1.4873343

This is an open access paper.

* ‘to be’ added on July 16, 2014.

Université de Montréal (Canada) collaborates with University of Houston (US) for a new theory and better solar cells

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Solar cell efficiency is not good as researchers from  l’Université de Montréal (UdeM, located in Quebec, Canada) and the University of Houston (UH, located Texas, US) note in a Jan. 29, 2014 joint UH/UdeM news release written by Lisa Merkl (UH) on EurekAlert,

“Scientists don’t fully understand what is going on inside the materials that make up solar cells. We were trying to get at the fundamental photochemistry or photophysics that describes how these cells work,” Bittner said [Eric Bittner, a John and Rebecca Moores Professor of Chemistry and Physics in UH’s College of Natural Sciences and Mathematics,].

Solar cells are made out of organic semiconductors – typically blends of materials. However, solar cells made of these materials have about 3 percent efficiency. Bittner added that the newer materials, the fullerene/polymer blends, only reach about 10 percent efficiency.

“There is a theoretical limit for the efficiency of the ideal solar cell – the Shockley-Queisser limit. The theory we published describes how we might be able to get above this theoretical limit by taking advantage of quantum mechanical effects,” Bittner said. “By understanding these effects and making use of them in the design of a solar cell, we believe you can improve efficiency.”

Silva [Carlos Silva, an associate professor at the Université de Montréal and Canada Research Chair in Organic Semiconductor Materials] added, “In polymeric semiconductors, where plastics form the active layer of solar cells, the electronic structure of the material is intimately correlated with the vibrational motion within the polymer chain. Quantum-mechanical effects due to such vibrational-electron coupling give rise to a plethora of interesting physical processes that can be controlled to optimize solar cell efficiencies by designing materials that best exploit them.”

Unfortunately, there’s no more information about this model other than this (from the news release),

“Our theoretical model accomplishes things that you can’t get from a molecular model,” he [Bittner] said. “It is mostly a mathematical model that allows us to look at a much larger system with thousands of molecules. You can’t do ordinary quantum chemistry calculations on a system of that size.”

The calculations have prompted a series of new experiments by Silva’s group to probe the outcomes predicted by their model.

Bittner and Silva’s next steps involve collaborations with researchers who are experts in making the polymers and fabricating solar cells.

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

Noise-induced quantum coherence drives photo-carrier generation dynamics at polymeric semiconductor heterojunctions by Eric R. Bittner & Carlos Silva. Nature Communications 5, Article number: 3119 doi:10.1038/ncomms4119 Published 29 January 2014

This article is behind a paywall although you can get a free preview via ReadCube Access.

Grossly warped ‘nanographene’, a brand new type of carbon

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A new of form carbon sounds exciting although the naming convention escapes me. Why call it ‘nanographene’ (albeit grossly warped) when graphene is already nanoscale? (For anyone who can explain this to me, please do let me know.) A July 15, 2013 news release on EurekAlert (it’s also available as a July 15, 2013 news item on ScienceDaily) describes the new form of carbon,

Bucking planarity, contorted sheets of graphene alter physical, optical and electronic properties of new material

Chemists at Boston College and Nagoya University in Japan have synthesized the first example of a new form of carbon, the team reports in the most recent online edition of the journal Nature Chemistry.

The new material consists of multiple identical pieces of grossly warped graphene, each containing exactly 80 carbon atoms joined together in a network of 26 rings, with 30 hydrogen atoms decorating the rim. Because they measure slightly more than a nanometer across, these individual molecules are referred to generically as “nanocarbons,” or more specifically in this case as “grossly warped nanographenes.”

There’s an explanation of why this discovery is special and how it was made (from,the news release),

Until recently, scientists had identified only two forms of pure carbon: diamond and graphite. Then in 1985, chemists were stunned by the discovery that carbon atoms could also join together to form hollow balls, known as fullerenes. Since then, scientists have also learned how to make long, ultra-thin, hollow tubes of carbon atoms, known as carbon nanotubes, and large flat single sheets of carbon atoms, known as graphene. The discovery of fullerenes was awarded the Nobel Prize in Chemistry in 1996, and the preparation of graphene was awarded the Nobel Prize in Physics in 2010.

Graphene sheets prefer planar, 2-dimensional geometries as a consequence of the hexagonal, chicken wire-like, arrangements of trigonal carbon atoms comprising their two-dimensional networks. The new form of carbon just reported in Nature Chemistry, however, is wildly distorted from planarity as a consequence of the presence of five 7-membered rings and one 5-membered ring embedded in the hexagonal lattice of carbon atoms.

Odd-membered-ring defects such as these not only distort the sheets of atoms away from planarity, they also alter the physical, optical, and electronic properties of the material, according to one of the principle authors, Lawrence T. Scott, the Jim and Louise Vanderslice and Family Professor of Chemistry at Boston College.

“Our new grossly warped nanographene is dramatically more soluble than a planar nanographene of comparable size,” said Scott, “and the two differ significantly in color, as well. Electrochemical measurements revealed that the planar and the warped nanographenes are equally easily oxidized, but the warped nanographene is more difficult to reduce.”

… By introducing multiple odd-membered ring defects into the graphene lattice, Scott and his collaborators have experimentally demonstrated that the electronic properties of graphene can be modified in a predictable manner through precisely controlled chemical synthesis.

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

A grossly warped nanographene and the consequences of multiple odd-membered-ring defects by Katsuaki Kawasumi, Qianyan Zhang, Yasutomo Segawa, Lawrence T. Scott, & Kenichiro Itami. Nature Chemistry (2013) doi:10.1038/nchem.1704  Published online 14 July 2013

This paper is behind a paywall. For those who would like more information but can’t get access to the paper at this time, there’s a brief July 15, 2015 news piece by Caryl Richards on the Chemistry World website.

Crowdfunding Qii, a foldable, soft keyboard made of a carbon nanotube/fullerene hybrid

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Canatu Ltd. is a Finnish company that’s trying to crowdfund its foldable, soft keyboard, Qii, on indiegogo. Here’s more about Canatu’s keyboard project from the Nov. 24, 2012 news item on Nanowerk,

Canatu Ltd., a developer of a new class of versatile carbon nanomaterial based custom films and sensors for flexible and formable touch devices, is launching Qii – the world’s first, truly mobile, rollable touch accessory.

The company appears to be creating a new class of product under the Qii brand name. From the indiegogo campaign description,

With Qii, your smartphone and your imagination, any surface can be effectively turned into a touch surface and any “dumb” object can be turned into a “smart” object. Nanotechnology and organic electronics make it possible. The idea is simple, but the applications are endless.

…

As our first Qii product, we’re offering a full QWERTY computer keyboard, including a number pad and function keys, wirelessly connected to your smartphone. Because its ultra thin and flexible, Qii is both full sized and pocket sized, so you’ll be able to effortlessly type and surf anywhere you go, be it in a café, the woods, or a car, train, bus or plane. It has an anti fingerprint coating to keep it clean and a textured surface for easy touch typing. It’s dirt and water resistant, so you don’t have to worry about spilling and it’s easily washable with soap and water. And, since Qii’s rollable electronics are printed, it’s tough.

Qii’s case is also a touchpad, allowing you to point, tap and scroll for easy surfing and graphical editing. You can use Qii on most any surface, so you can check your email on your friend’s belly, update your Facebook on your pet, or write your next novel on your pillow.

Some keyboards claim to be rollable, but you can’t roll them up and fit them in your pocket. We use a new kind of flexible transparent electronic film together with a new kind of touch sensing technology that can sense both position and force to create a compact and portable and programmable touch surface.

…

Qii will work with iPhone, iPod, iPad, Android, iPhone, Blackberry, Windows Phone, and Palm phones according to each platform’s available QWERTY keyboard and pointer standards.

Intriguing, non? You might want to watch this video for a demonstration,

There is a very brief description of the technology in the campaign material,

Our team has been working for years with our partners to bring Qii to life. Together we have developed new carbon based nanomaterials, new dry printing manufacturing techniques and now new, ultra-high transparency, flexible, bendable, stretchable, rollable and foldable touch technologies and unique touch algorithms to make Qii possible. It starts with our flexible, transparent, electrically conductive film made with a new carbon nanomaterial connected to state-of-the art sensing electronics to make a flexible, transparent touch sensing surface that determines both your finger’s position and force.

We’ll introduce the Qii in pliable hard coated plastic, but, in the future, the sensor can be printed on most anything, even paper, rubber or fabric.

I took a look at the Canatu website and found this information about a material they’ve developed and named, NanoBuds® and which I believe forms the basis for the company’s proposed Qii keyboard,

Canatu has developed a new material, the Carbon NanoBud®, which is a hybrid of Carbon Nanotubes and fullerenes. The hybridization is achieved directly in the material synthesis process and the resulting material combines the best features of both fullerenes and nanotubes.

…

Canatu’s first products focus on taking advantage of the high conductivity, high aspect ratio, low work function, chemical stability and mechanical flexibility of NanoBuds® to make the world’s highest performance carbon based transparent conductive film for transparent conductors in touch, haptics, displays and photovoltaics. These films, consisting of randomly oriented deposits of NanoBuds on polymer or glass substrates, are flexible, bendable, stretchable and have excellent transparency conductivity performance as shown below. [emphasis mine]

David Brown, the company’s Chief Technical Officer (CTO) originally announced the crowdfunding Qii campaign would take place on Kickstarter in Dan Rogers’s Oct. 10, 2012 article for Plastic Electronics,

An accessory using a novel nanomaterial touchscreen will be launched via the Kickstarter project in the coming weeks, according to nanotechnology developer Canatu.

Based in Finland, Canatu supplies carbon NanoBuds that can be used as a conductive layer alternative to indium tin oxide, which is considered too brittle for flexible electronics.

I’m not sure what happened with the ‘Kickstarter’ plans but the indiegogo campaign has 41 days left as Canatu tries to raise $1,850,000 by Jan. 6, 2013. The company must raise the entire amount requested or it receives nothing.

Good luck to the folks at Canatu. Qii looks like a product which would make moving around much easier. Imagine not having to lug your laptop or tablet around while enjoying the benefits of a full size keyboard.

Where do buckyballs come from?

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I’ve always wondered where buckyballs come from (as have scientists for the last 25 years) and now there’s an answer of sorts  (from the July 31, 2012 Florida State University news release Note: I have removed some links),

“We started with a paste of pre-existing fullerene molecules mixed with carbon and helium, shot it with a laser, and instead of destroying the fullerenes we were surprised to find they’d actually grown,” they wrote. The fullerenes were able to absorb and incorporate carbon from the surrounding gas.

By using fullenes  that contained heavy metal atoms in their centers, the scientists showed that the carbon cages remained closed throughout the process.

“If the cages grew by splitting open, we would have lost the metal atoms, but they always stayed locked inside,” Dunk [Paul Dunk, a doctoral student in chemistry and biochemistry at Florida State and lead author of the study published in Nature Communications] noted.

The researchers worked with a team of MagLab chemists using the lab’s 9.4-tesla Fourier transform ion cyclotron resonance mass spectrometer to analyze the dozens of molecular species produced when they shot the fullerene paste with the laser. The instrument works by separating molecules according to their masses, allowing the researchers to identify the types and numbers of atoms in each molecule. The process is used for applications as diverse as identifying oil spills, biomarkers and protein structures.

Dexter Johnson in his Aug. 6, 2012 posting on the Nanoclast blog on the IEEE (Institute of Electrical and Electronics Engineers) provides some context and commentary (Note: I have removed a link),

When Richard Smalley, Robert Curl, James Heath, Sean O’Brien, and Harold Kroto prepared the first buckminsterfullerene (C60) (or buckyball), they kicked off the next 25 years of nanomaterial science.

Here’s an artist’s illustration of  what these scientists have achieved, fullerene cage growth,

An artist’s representation of fullerene cage growth via carbon absorption from surrounding hot gases. Some of the cages contain lanthanum metal atoms. (Image courtesy National Science Foundation) [downloaded from Florida State University website]

 As I noted earlier I’m not alone in my fascination (from the news release),

Many people know the buckyball, also known by scientists as buckminsterfullerene, carbon 60 or C60, from the covers of their school chemistry textbooks. Indeed, the molecule represents the iconic image of “chemistry.” But how these often highly symmetrical, beautiful molecules with  fascinating properties form in the first place has been a mystery for a quarter-century. Despite worldwide investigation since the 1985 discovery of C60, buckminsterfullerene and other, non-spherical C60 molecules — known collectively as fullerenes — have kept their secrets. How? They’re born under highly energetic conditions and grow ultra-fast, making them difficult to analyze.

“The difficulty with fullerene formation is that the process is literally over in a flash — it’s next to impossible to see how the magic trick of their growth was performed,” said Paul Dunk, a doctoral student in chemistry and biochemistry at Florida State and lead author of the work.

There’s more than just idle curiosity at work (from the news release),

The buckyball research results will be important for understanding fullerene formation in extraterrestrial environments. Recent reports by NASA showed that crystals of C60 are in orbit around distant suns. This suggests that fullerenes may be more common in the universe than previously thought.

“The results of our study will surely be extremely valuable in deciphering fullerene formation in extraterrestrial environments,” said Florida State’s Harry Kroto, a Nobel Prize winner for the discovery of C60 and co-author of the current study.

The results also provide fundamental insight into self-assembly of other technologically important carbon nanomaterials such as nanotubes and the new wunderkind of the carbon family, graphene.

H/T to Nanowerk’s July 31, 2012 news item titled, Decades-old mystery how buckyballs form has been solved. In addition to Florida State University, National High Magnetic Field Laboratory (or MagLab), the CNRS  (Centre National de la Recherche Scientifique)Institute of Materials in France and Nagoya University in Japan were also involved in the research.

Miah and the Olympics; birth of the buckyball

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Given that the Winter Olympics are due to open later this week in Vancouver (Canada), there is a  flurry of interest in gene doping and other means of enhancing athletic performance. (I’m mentioning this because developments in elite athletics find their way into consumer markets and because of my interest in human enhancement.) For example, the University of British Columbia (UBC) is hosting,

Sport, Ethics and Technology: Is High Performance Sport Inconsistent with Ideals and Ethics?

Date/time: Monday, February 8, 8 p.m.

Location: Chan Centre for the Performing Arts
University of British Columbia
6265 Crescent Road, Vancouver
For a map and closest parking, visit: www.maps.ubc.ca?130

As the Vancouver 2010 Olympic Winter Games approach, Olympic athletes will come under close public scrutiny.  New technology will offer unexpected advantages that will challenge the boundaries of what is considered a level playing field.

And given those challenges, how do we determine what is ethical and fair? These questions are explored with Richard Pound followed by a panel discussion with Jim Rupert, Beckie Scott and other participants.

*Richard Pound is a former Olympic swimmer, McGill Chancellor and World Anti-Doping Agency Chairman.

*Jim Rupert is an associate professor in the School of Human Kinetics at UBC. His research looks at future trends in doping and doping control as it pertains to genetics and “gene-doping.”

*Beckie Scott is a former Olympic cross-country ski racer who currently serves as a member of the IOC.

This event is one of five provocative dialogues presented by UBC’s Sport and Society series during February and March. Find details at: http://bit.ly/9LuMXO

Friday, Feb. 5, 2010, the lead article in Section B of The Vancouver Sun by Margaret Munro was (print version), Gene Doping; The latest way to boost performance. The article noted that Andy Miah, at the University of the West of Scotland, in contrast to Olivier Rabin and Theodore Friedmann, the experts (whose study was just published in the journal Science) quoted in the article, suggests that gene doping may be safer than current methods of enhancing performance.

I have mentioned Andy before (here in my series on human enhancement and here regarding a book he edited on art and the future). His response to the Rabin/Friedmann concerns is here. An abstract of Rabin and Friedmann’s article is available here but the full article is behind a paywall.

Andy was also featured in an article in The WestEnder (a Vancouver community newspaper) by Jackie Wong titled (in the print version), New-media [sic] centre seeks to democratize Olympic coverage. From the article,

“We can say that Vancouver 2010 is the first truly digital Olympic Games,” says Andy Miah, chair in Ethics and Emerging Technologies in the School of Media, Language, and Music at the University of the West of Scotland. Miah has been researching new media and the Olympics for 10 years, at six Olympic Games.

Andy has written an essay about new media and its role at the Vancouver 2010 Olympics at Huffington Post. From the essay,

…. perhaps the most interesting dimension of Vancouver’s media culture is the rise of three other media entities, the first of which is the W2 Centre on Hastings, led by Irwin Oostindie. W2 is a cultural and arts infrastructure, serving the independent sector. It will run an extensive programme of art, debate and cultural experiences, some of which will have buy in from the Vancouver Organizing Committee (VANOC), while other elements will be more independent. To this end, W2 will serve as a bridge between the privileged participants and the critical commentators around Games time. For example, they will host the Legal Observers programme, headed up by the Pivot Legal Society and BC Civil Liberties Association, which will monitor the operations of Olympic security during Games time. It will also host a cultural collaboration between the London 2012 and Vancouver 2010 Cultural Olympiads, as part of the UK’s Abandon Normal Devices festival, led by England’s Northwest.

You can read more here.

I’ve now mentioned the two areas that Andy sees as the two major controversies from the Vancouver Olympics, doping and new media activism.

One final note on this, Andy will be bringing a team of about 10 students from his university in Scotland who will be blogging from this site, Culture@tO Vancouver 2010. I’m not sure what the start date will be, presumably Feb. 12, 2010 when the games open.

Bucky balls are the popular name for the buckminsterfullerene (aka fullerene). Named for Buckminster Fuller, the molecule resembles one of Fuller’s geodesic domes. (There’s a geodesic dome in Vancouver which houses our local science centre and during the Olympics it will be home to the Sochi [host for 2014 Olympics], Russia pavilion.) The fullerene was first discovered at Rice University in Texas and this year marks its 25th anniversary and what many describe as the birth of nanotechnology. In celebration, the university is hosting a technical symposium.  From the news item on Nanowerk,

On Oct. 11-13, the best minds in carbon nanotechnology will gather at Rice University for a technical symposium during the Year of Nano, a series of events at the university celebrating the 25th anniversary of nano’s big bang.

Hmmm … I may have gone a little ‘link happy’ today. Tomorrow I should be looking at nano sponges and patents. Later this week I expect to be posting my interview with Dr. Cheryl Geisler, the new dean for Simon Fraser University’s new Faculty of Communication, Art and Technology (FCAT).