Tag Archives: nanosheets

IBM and a 5 nanometre chip

If this continues, they’re going to have change the scale from nano to pico. IBM has announced work on a 5 nanometre (5nm) chip in a June 5, 2017 news item on Nanotechnology Now,

IBM (NYSE: IBM), its Research Alliance partners GLOBALFOUNDRIES and Samsung, and equipment suppliers have developed an industry-first process to build silicon nanosheet transistors that will enable 5 nanometer (nm) chips. The details of the process will be presented at the 2017 Symposia on VLSI Technology and Circuits conference in Kyoto, Japan. In less than two years since developing a 7nm test node chip with 20 billion transistors, scientists have paved the way for 30 billion switches on a fingernail-sized chip.

A June 5, 2017 IBM news release, which originated the news item, spells out some of the details about IBM’s latest breakthrough,

The resulting increase in performance will help accelerate cognitive computing [emphasis mine], the Internet of Things (IoT), and other data-intensive applications delivered in the cloud. The power savings could also mean that the batteries in smartphones and other mobile products could last two to three times longer than today’s devices, before needing to be charged.

Scientists working as part of the IBM-led Research Alliance at the SUNY Polytechnic Institute Colleges of Nanoscale Science and Engineering’s NanoTech Complex in Albany, NY achieved the breakthrough by using stacks of silicon nanosheets as the device structure of the transistor, instead of the standard FinFET architecture, which is the blueprint for the semiconductor industry up through 7nm node technology.

“For business and society to meet the demands of cognitive and cloud computing in the coming years, advancement in semiconductor technology is essential,” said Arvind Krishna, senior vice president, Hybrid Cloud, and director, IBM Research. “That’s why IBM aggressively pursues new and different architectures and materials that push the limits of this industry, and brings them to market in technologies like mainframes and our cognitive systems.”

The silicon nanosheet transistor demonstration, as detailed in the Research Alliance paper Stacked Nanosheet Gate-All-Around Transistor to Enable Scaling Beyond FinFET, and published by VLSI, proves that 5nm chips are possible, more powerful, and not too far off in the future.

Compared to the leading edge 10nm technology available in the market, a nanosheet-based 5nm technology can deliver 40 percent performance enhancement at fixed power, or 75 percent power savings at matched performance. This improvement enables a significant boost to meeting the future demands of artificial intelligence (AI) systems, virtual reality and mobile devices.

Building a New Switch

“This announcement is the latest example of the world-class research that continues to emerge from our groundbreaking public-private partnership in New York,” said Gary Patton, CTO and Head of Worldwide R&D at GLOBALFOUNDRIES. “As we make progress toward commercializing 7nm in 2018 at our Fab 8 manufacturing facility, we are actively pursuing next-generation technologies at 5nm and beyond to maintain technology leadership and enable our customers to produce a smaller, faster, and more cost efficient generation of semiconductors.”

IBM Research has explored nanosheet semiconductor technology for more than 10 years. This work is the first in the industry to demonstrate the feasibility to design and fabricate stacked nanosheet devices with electrical properties superior to FinFET architecture.

This same Extreme Ultraviolet (EUV) lithography approach used to produce the 7nm test node and its 20 billion transistors was applied to the nanosheet transistor architecture. Using EUV lithography, the width of the nanosheets can be adjusted continuously, all within a single manufacturing process or chip design. This adjustability permits the fine-tuning of performance and power for specific circuits – something not possible with today’s FinFET transistor architecture production, which is limited by its current-carrying fin height. Therefore, while FinFET chips can scale to 5nm, simply reducing the amount of space between fins does not provide increased current flow for additional performance.

“Today’s announcement continues the public-private model collaboration with IBM that is energizing SUNY-Polytechnic’s, Albany’s, and New York State’s leadership and innovation in developing next generation technologies,” said Dr. Bahgat Sammakia, Interim President, SUNY Polytechnic Institute. “We believe that enabling the first 5nm transistor is a significant milestone for the entire semiconductor industry as we continue to push beyond the limitations of our current capabilities. SUNY Poly’s partnership with IBM and Empire State Development is a perfect example of how Industry, Government and Academia can successfully collaborate and have a broad and positive impact on society.”

Part of IBM’s $3 billion, five-year investment in chip R&D (announced in 2014), the proof of nanosheet architecture scaling to a 5nm node continues IBM’s legacy of historic contributions to silicon and semiconductor innovation. They include the invention or first implementation of the single cell DRAM, the Dennard Scaling Laws, chemically amplified photoresists, copper interconnect wiring, Silicon on Insulator, strained engineering, multi core microprocessors, immersion lithography, high speed SiGe, High-k gate dielectrics, embedded DRAM, 3D chip stacking and Air gap insulators.

I last wrote about IBM and computer chips in a July 15, 2015 posting regarding their 7nm chip. You may want to scroll down approximately 55% of the way where I note research from MIT (Massachusetts Institute of Technology) about metal nanoparticles with unexpected properties possibly having an impact on nanoelectronics.

Getting back to IBM, they have produced a slick video about their 5nm chip breakthrough,

Meanwhile, Katherine Bourzac provides technical detail in a June 5, 2017 posting on the Nanoclast blog (on the IEEE [Institute of Electrical and Electronics Engineers] website), Note: A link has been removed,

Researchers at IBM believe the future of the transistor is in stacked nanosheets. …

Today’s state-of-the-art transistor is the finFET, named for the fin-like ridges of current-carrying silicon that project from the chip’s surface. The silicon fins are surrounded on their three exposed sides by a structure called the gate. The gate switches the flow of current on, and prevents electrons from leaking out when the transistor is off. This design is expected to last from this year’s bleeding-edge process technology, the “10-nanometer” node, through the next node, 7 nanometers. But any smaller, and these transistors will become difficult to switch off: electrons will leak out, even with the three-sided gates.

So the semiconductor industry has been working on alternatives for the upcoming 5 nanometer node. One popular idea is to use lateral silicon nanowires that are completely surrounded by the gate, preventing electron leaks and saving power. This design is called “gate all around.” IBM’s new design is a variation on this. In their test chips, each transistor is made up of three stacked horizontal sheets of silicon, each only a few nanometers thick and completely surrounded by a gate.

Why a sheet instead of a wire? Huiming Bu, director of silicon integration and devices at IBM, says nanosheets can bring back one of the benefits of pre-finFET, planar designs. Designers used to be able to vary the width of a transistor to prioritize fast operations or energy efficiency. Varying the amount of silicon in a finFET transistor is not practicable because it would mean making some fins taller and other shorter. Fins must all be the same height due to manufacturing constraints, says Bu.

IBM’s nanosheets can range from 8 to 50 nanometers in width. “Wider gives you better performance but takes more power, smaller width relaxes performance but reduces power use,” says Bu. This will allow circuit designers to pick and choose what they need, whether they are making a power efficient mobile chip processor or designing a bank of SRAM memory. “We are bringing flexibility back to the designers,” he says.

The test chips have 30 billion transistors. …

It was a struggle trying to edit Bourzac’s posting with its good detail and clear writing. I encourage you to read it (June 5, 2017 posting) in its entirety.

As for where this drive downwards to the ‘ever smaller’ is going, there’s Dexter’s Johnson’s June 29, 2017 posting about another IBM team’s research on his Nanoclast blog on the IEEE website (Note: Links have been removed),

There have been increasing signs coming from the research community that carbon nanotubes are beginning to step up to the challenge of offering a real alternative to silicon-based complementary metal-oxide semiconductor (CMOS) transistors.

Now, researchers at IBM Thomas J. Watson Research Center have advanced carbon nanotube-based transistors another step toward meeting the demands of the International Technology Roadmap for Semiconductors (ITRS) for the next decade. The IBM researchers have fabricated a p-channel transistor based on carbon nanotubes that takes up less than half the space of leading silicon technologies while operating at a lower voltage.

In research described in the journal Science, the IBM scientists used a carbon nanotube p-channel to reduce the transistor footprint; their transistor contains all components to 40 square nanometers [emphasis mine], an ITRS roadmap benchmark for ten years out.

One of the keys to being able to reduce the transistor to such a small size is the use of the carbon nanotube as the channel in place of silicon. The nanotube is only 1 nanometer thick. Such thinness offers a significant advantage in electrostatics, so that it’s possible to reduce the device gate length to 10 nanometers without seeing the device performance adversely affected by short-channel effects. An additional benefit of the nanotubes is that the electrons travel much faster, which contributes to a higher level of device performance.

Happy reading!

Novel self-assembly at 102 atoms

A Jan. 13, 2017 news item on ScienceDaily announces a discovery about self-assembly of 102-atom gold nanoclusters,

Self-assembly of matter is one of the fundamental principles of nature, directing the growth of larger ordered and functional systems from smaller building blocks. Self-assembly can be observed in all length scales from molecules to galaxies. Now, researchers at the Nanoscience Centre of the University of Jyväskylä and the HYBER Centre of Excellence of Aalto University in Finland report a novel discovery of self-assembling two- and three-dimensional materials that are formed by tiny gold nanoclusters of just a couple of nanometres in size, each having 102 gold atoms and a surface layer of 44 thiol molecules. The study, conducted with funding from the Academy of Finland and the European Research Council, has been published in Angewandte Chemie.

A Jan. 13, 2017 Academy of Finland press release, which originated the news item, provides more technical information about the work,

The atomic structure of the 102-atom gold nanocluster was first resolved by the group of Roger D Kornberg at Stanford University in 2007 (2). Since then, several further studies of its properties have been conducted in the Jyväskylä Nanoscience Centre, where it has also been used for electron microscopy imaging of virus structures (3). The thiol surface of the nanocluster has a large number of acidic groups that can form directed hydrogen bonds to neighbouring nanoclusters and initiate directed self-assembly.

The self-assembly of gold nanoclusters took place in a water-methanol mixture and produced two distinctly different superstructures that were imaged in a high-resolution electron microscope at Aalto University. In one of the structures, two-dimensional hexagonally ordered layers of gold nanoclusters were stacked together, each layer being just one nanocluster thick. Modifying the synthesis conditions, also three-dimensional spherical, hollow capsid structures were observed, where the thickness of the capsid wall corresponds again to just one nanocluster size (see figure).

While the details of the formation mechanisms of these superstructures warrant further systemic investigations, the initial observations open several new views into synthetically made self-assembling nanomaterials.

“Today, we know of several tens of different types of atomistically precise gold nanoclusters, and I believe they can exhibit a wide variety of self-assembling growth patterns that could produce a range of new meta-materials,” said Academy Professor Hannu Häkkinen, who coordinated the research at the Nanoscience Centre. “In biology, typical examples of self-assembling functional systems are viruses and vesicles. Biological self-assembled structures can also be de-assembled by gentle changes in the surrounding biochemical conditions. It’ll be of great interest to see whether these gold-based materials can be de-assembled and then re-assembled to different structures by changing something in the chemistry of the surrounding solvent.”

“The free-standing two-dimensional nanosheets will bring opportunities towards new-generation functional materials, and the hollow capsids will pave the way for highly lightweight colloidal framework materials,” Postdoctoral Researcher Nonappa (Aalto University) said.

Professor Olli Ikkala of Aalto University said: “In a broader framework, it has remained as a grand challenge to master the self-assemblies through all length scales to tune the functional properties of materials in a rational way. So far, it has been commonly considered sufficient to achieve sufficiently narrow size distributions of the constituent nanoscale structural units to achieve well-defined structures. The present findings suggest a paradigm change to pursue strictly defined nanoscale units for self-assemblies.”

References:

(1)    Nonappa, T. Lahtinen, J.S. Haataja, T.-R. Tero, H. Häkkinen and O. Ikkala, “Template-Free Supracolloidal Self-Assembly of Atomically Precise Gold Nanoclusters: From 2D Colloidal Crystals to Spherical Capsids”, Angewandte Chemie International Edition, published online 23 November 2016, DOI: 10.1002/anie.201609036

(2)    P. Jadzinsky et al., “Structure of a thiol-monolayer protected gold nanoparticle at 1.1Å resolution”, Science 318, 430 (2007)

(3)    V. Marjomäki et al., “Site-specific targeting of enterovirus capsid by functionalized monodispersed gold nanoclusters”, PNAS 111, 1277 (2014)

Here’s the figure mentioned in the news release,

Figure: 2D hexagonal sheet-like and 3D capsid structures based on atomically precise gold nanoclusters as guided by hydrogen bonding between the ligands. The inset in the top left corner shows the atomic structure of one gold nanocluster.

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

Template-Free Supracolloidal Self-Assembly of Atomically Precise Gold Nanoclusters: From 2D Colloidal Crystals to Spherical Capsids by Dr. Nonappa, Dr. Tanja Lahtinen, M. Sc. Johannes. S. Haataja, Dr. Tiia-Riikka Tero, Prof. Hannu Häkkinen, and Prof. Olli Ikkala. Angewandte Chemie International Edition Volume 55, Issue 52, pages 16035–16038, December 23, 2016 Version of Record online: 23 NOV 2016 DOI: 10.1002/anie.201609036

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

This paper is behind a paywall.

Hydrogels and cartilage; repurposing vehicles in space; big bang has ‘fingerprints’

The American Institute of Physics (AIP) has made a selection of four articles freely available (h/t Mar. 9, 2015 news item on Azonano).

From a March 6, 2015 AIP news release,

WASHINGTON D.C., March 6, 2015 — The following articles are freely available online from Physics Today (www.physicstoday.org), the world’s most influential and closely followed magazine devoted to physics and the physical science community.

You are invited to read, share, blog about, link to, or otherwise enjoy:

1) STIFF AND SUPPLE CARTILAGE SUBSTITUTE

Physics Today‘s Ashley Smart reports on hydrogels that mimic the tricky nature of cartilage thanks to magnetically aligned nanosheets.

“In the realm of bioengineering, hydrogels are something of an all-purpose material. Made up of networks of interlinked, hydrophilic polymers, they tend to be soft, biocompatible, and highly absorbent…. The new material mimics the articular cartilage that lubricates our joints: It can support a heavy load along one direction while stretching and shearing with ease in the others.”

MORE: http://dx.doi.org/10.1063/PT.3.2707

2) GIVING SPACECRAFT A SECOND LEASE ON LIFE WHILE HURTLING THROUGH THE COSMOS

Physics Today‘s Toni Feder reports on the innovative processes undertaken to repurpose various spacecraft in flight, including Kepler, Voyager, Deep Impact, Spitzer, and the Hubble Space Telescope.

“A comeback like Kepler’s is ‘not unique, but it’s unusual,’ says Derek Buzasi of Florida Gulf Coast University, who reinvented the Wide-Field Infrared Explorer (WIRE) after it failed following its 1999 launch. ‘Spacecraft are built for a specialized purpose, so they are hard to repurpose. You have to come up with something they are capable of at the same time they are incapable of their original mission.’

Deep Impact’s original mission was to hurl a copper ball at a comet and watch the impact. In its continued form as EPOXI, the spacecraft went on to visit another comet and, on the way, served as an observatory for user- proposed targets.”

MORE: http://dx.doi.org/10.1063/PT.3.2713

3) CONGRESSMAN & FUSION RESEARCHER REFLECTS ON SCIENCE POLICY

Physics Today‘s David Kramer interviews Rush Holt, the New Jersey congressman who retired from office and this past December took the helm of the American Association for the Advancement of Science.

“PT: What do you consider to be your accomplishments in Congress?

HOLT: I focused a lot on science education. Our real problem is not that we’re failing to produce excellent scientists, because we are [producing them], but rather that we have failed to maintain an appreciation for and understanding of science in the general population. I was able to keep a spotlight on the need but wasn’t able to accomplish as much as I wanted. We got science included in the subjects emphasized by federal law. But we haven’t really improved teacher professional development and other things we need to do.”

MORE: http://dx.doi.org/10.1063/PT.3.2714

4) PARTICLE PHYSICS AND THE COSMIC MICROWAVE BACKGROUND

In this article, physics researchers John Carlstrom, Tom Crawford and Lloyd Knox discuss the fingerprints of the Big Bang and quantum fluctuations in the early universe, which may soon reveal physics at unprecedented energy scales.

“With its empirical successes, inflation is by consensus the best paradigm—notwithstanding some notable dissenting views—for the mechanism that generated the primordial density fluctuations that led to all structure in the universe. Its success has motivated physicists to search for the siblings of those fluctuations, the gravitational waves, via their signature in the polarization of the CMB. If discovered, that gravitational imprint would open up an observational window onto quantum gravitational effects, extremely early times, and extremely high energies.”

MORE: http://dx.doi.org/10.1063/PT.3.2718

I have checked; all of the links do lead to the articles.

Taking photos and videos in near darkness

Who hasn’t found wanted to take a picture in a situation where there’s very little light? It seems scientists at SUNY (State University of New York) College of Nanoscale Science and Engineering (CNSE) have found a way to solve the problem. From a Jan. 30, 2014 news item on Azonano,

When the lights went out at the big game, fans and film crews struggled to take a decent picture in the darkness. Those same folks will be cheering the latest research by a team of SUNY College of Nanoscale Science and Engineering (CNSE) scientists, which makes brilliant video and pictures possible even if the lights go out.

Dark and blurry low light photos could soon be a thing of the past, thanks to the development of game-changing ultrathin “nanosheets,” which could dramatically improve imaging technology used in everything from cell phone cameras, video cameras, solar cells, and even medical imaging equipment such as MRI machines.

As a result, this technology is perfectly suited for inclusion in a wide variety of everyday devices, including today’s smartphones, which are often used to take pictures, but suffer from limitations in low light environments. This research could allow even novice photographers to take sharper images, even in the midst of a blackout during the biggest game of the year.

A SUNYCNSE research profile titled: SUNY College of Nanoscale Science and Engineering Scientists Publish Game-Changing Semiconductor Nanosheets Research That Could Revolutionize Cameras in Low-Light Environments provides more technical details about the research,

Leading-edge research by a team of SUNY College of Nanoscale Science and Engineering (CNSE) scientists has been published in ACS Nano after the scientists evaluated ultrathin indium(III) selenide (In2Se3) nanosheets and discovered that their electrical resistance drops significantly when exposed to light. This effect, known as a photoconductive response, can be used to make a photodetector or light sensor, and because the two-dimensional nanosheets exhibited such a strong photoconductive response across a broad light spectrum and simultaneously resist chemical contamination, this research could lead to a revolution in extreme low-light, high-resolution imaging products and applications, such as consumer and professional cameras and video cameras, for example.

The team combined a variety of cutting-edge tools and methods, including scanning electron microscopy (SEM) to identify the nanosheets; atomic force microscopy (AFM) to measure their thickness; X-ray diffractometry (XRD) and selected area electron diffraction (SAED) combined with high-resolution images from transmission electron microscopy (TEM) to examine nano-layer details such as the crystallographic phase and morphology of the sample; and energy-dispersive X-ray spectrometry (EDS) and auger electron spectrometry (AES) to explore the sample’s homogeneity. As the photoconductive material’s properties were characterized, the CNSE research group found that the material is extremely resistant to contamination. Additionally, the team utilized a green LED to direct pulsed light at the nanosheets and found that they exhibited a reliable response to light and an excellent response time between 18 and 73 milliseconds, indicating that In2Se3 nanosheets could be a highly effective material for real-time imaging purposes.

The nanosheets were also tested for the ability to detect light and for light responsivity, or the ratio of generated photocurrent to incident light power. The researchers noted that the photoconductive response of the nanosheets, which had a thickness of 3.9 nanometers, was demonstrably higher than other 2D photoresistors across a broad light spectrum, including Ultraviolet, visible light, and infrared, making them suitable for use in a wide-range of imaging devices.

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

Extraordinary Photoresponse in Two-Dimensional In2Se3 Nanosheets by Robin B. Jacobs-Gedrim, Mariyappan Shanmugam, Nikhil Jain, Christopher A. Durcan, Michael T. Murphy, Thomas M. Murray, Richard J. Matyi, Richard L. Moore, II, and Bin Yu.  ACS Nano (2014), vol. 8, no. 1, pp. 514-21

This is a PDF of the document and is being made available by the researchers and their institution.

Mop up the oil spills with nanosheets from Deakin University and The Conversation

Researchers from Deakin University (Australia) have developed a new material, boron-based nanosheets, which can mop up oil spills more efficiently than current methods and are recyclable. From the May 1, 2013 news item on Nanowerk, (Note: A link has been removed)

In Nature Communications today (“Porous boron nitride nanosheets for effective water cleaning”), we showed how we produced, probably for the first time, nanosheets that could revolutionise oil spill clean ups and water purification.

Not only do our nanosheets absorb 33 times their weight in oil, they’re also recyclable.

Ordinarily there’d be a news release from Deakin University but these researchers appear to have taken a different approach posting on a website called The Conversation. This is a very interesting science communicaton initiative from Australia and I will be digressing for a moment. Here’s a description of the initiative from their Who We Are page,

The Conversation is an independent source of news and views, sourced from the academic and research community and delivered direct to the public.

Our team of professional editors work with university, CSIRO and research institute experts to unlock their knowledge for use by the wider public.

Access to independent, high-quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to allow for better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversations.

We have introduced new protocols and controls to help rebuild trust in journalism. All authors and editors sign up to our Editorial Charter and Code of Ethics. And all contributors must abide by our Community Standards policy. We only allow authors to write on a subject on which they have proven expertise, which they must disclose alongside their article. Authors’ funding and potential conflicts of interest must be disclosed. Failure to do so carries a risk of being banned from contributing to the site.

Since our launch in March 2011, we’ve grown to become one of Australia’s largest independent news and commentary sites. Around 35% of our readers are from outside Australia.

We believe in open access and the free-flow of information. The Conversation is a free resource: free to read (we’ll never go behind a paywall), and free to share or republish under Creative Commons. All you need to do is follow our simple guidelines. We have also become an indispensable media resource: providing free content, ideas and talent to follow up for press, web, radio or TV.

They believe in open access and the free-flow of information as long as you don’t edit the article, etc. Here are five of the guidelines (from the Republishing guidelines page),

Republishing guidelines, for print and online

  1. Unless you have express permission from the author, you can’t edit our material, except to reflect relative changes in time, location and editorial style. (For example, “yesterday” can be changed to “last week,” and “Canberra, ACT.” to “Canberra” or “here”). If you need to materially edit our content, please contact our External Relations Manager.
  2. You have to credit our authors and partner institutions — ideally in the byline. We prefer “Author Name, Institution” (for example, Qing Wang, Warwick Business School).
  3. You have to credit The Conversation — ideally at the top of the article and include our logo — with a link back to either our home page, The Conversation, or (preferably) the specific article URL on The Conversation website.
  4. If space is tight, you can run the first few lines of the article and then say: “Read the full article at The Conversation” with a link back to the article page on our site.
  5. If you’re republishing online, you must use our page view counter, link to us, and include links from our story. Our page view counter is a small pixel-ping image (invisible to the eye) that allows us to know when our content is republished, and gives our authors sense of the size of audience and which publications they’re reaching. It is a condition of our guidelines that you include our counter. If you use the “republish” button that accompanies each article then you’ll capture our page counter.
  6. ….

Since I usually cut and paste parts of articles and news releases and often intersperse with my own comments and I don’t have the technical skills to use their page view counter, I won’t be using anything directly from The Conversation. I view my role as a curator (bringing together pieces of information from disparate sources) and a ‘connector’. To encourage connections, I don’t usually include a full news release or article as I suggest my readers look at the original or seek out the other sources I’ve included if they want more information.

Back to the boron nitride nanosheets and the news item on Nanowerk,

We found that porous boron nitride nanosheets have a couple of properties that make them particularly suitable for absorbing organic (carbon-based) contaminants, such as oil or dyes.

The nanosheets are made of a few layers of boron nitride atomic planes, and these sheets have a large number of holes.

It’s these holes that increase the surface area of the nanosheets to a huge 1,425m2 a gram.
This means one gram of porous boron nitride nanosheets has the same surface area as nearly 5.5 tennis courts – so plenty of surface for absorption.

Another advantage is that the saturated boron nitride nanosheets can be cleaned for reuse by simply heating in air for two hours.

The absorbed oil is burned off, leaving the nanosheets clean and free to absorb again.

To make our porous nanosheets, boron oxide powder and guanidine hydrochloride are mixed in methane and heated at 1,100C for several hours in nitrogen gas.

The news item on Nanowerk is illustrated with images and provides more detail as does the May 1, 2013 article (Don’t cry over spilled oil – use nanosheets) on The Conversation.

For those who’d like to read the published research, here’s a link to and a citation for it,

Porous boron nitride nanosheets for effective water cleaning by Weiwei Lei, David Portehault, Dan Liu, Si Qin, & Ying Chen. Nature Communications 4, Article number: 1777 doi:10.1038/ncomms2818 Published 30 April 2013

The article is behind a paywall.

Interestingly scientists in China have developed an entirely different material with similar properties for mopping up oil spills as per my Feb. 27, 2013 posting titled, Bacterial cellulose could suck up pollutants from oil spills.

ETA May 6, 2013: Dexter Johnson has commented on an outstanding issue with the Deakin University research and other such initiatives: a lack of commercialization efforts. From his May 4, 2013 posting on his Nanoclast blog (found on the IEEE [Institute of Electrical and Electronics Engineers] website), Note: A link has been removed,

In fact, there are a variety of nanomaterials for these applications [oil spill remediation and water purification]—so many of them that there are catalogues to guide you through them.  But not so fast. As yet, no one is bothering to commercialize them so that they are available for the next oil spill.

Dexter provides worthwhile context and some provocative comments on how to ‘encourage’ commercialization of nanotechnology-enabled oil spill remediation/water purification  products.