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Above: IBM's carbon nanotubes have tiny circuits that are fractions of a meter apart.Image Credit: IBM Carbon nanotubes are the leading candidate to replace silicon in semiconductor chips after the decades-long run of silicon electronics runs out. And IBM is hoping to usher along that transition with a new breakthrough being announced today.In the October 2 issue of the journal Science, IBM researchers say they have overcome one of the most daunting challenges around carbon nanotube transistors, which are the building blocks of electronic circuits with dimensions that are measured in billionths of a meter. Carbon nanotubes may be...

IBM boffins have been given a tidy $3bn cash pile to solve a problem that lurks not too far in our future. That problem is the imminent breakdown in conventional chip operation and chip materials as we shrink transistor gates from today's 14nm process size to 10nm and 7nm. At around 7nm, which most industry observers expect we will hit in the early 2020s, things start to get really unpleasant. More and more jostling electrons jump in and out of gates against processor designers' wishes, leading to a frustrating problem known as gate current leakage. ... These investment areas include:...

© ShutterstockChinese scientists at Tsinghua University in Beijing have managed to grow a carbon nanotube (CNT) that is just over half a metre long – over double their previous best.For two hours the group used chemical vapour deposition to grow the long nanotube on a silica substrate. The team managed to improve their technique so much as they discovered that CNT growth is controlled by kinetics and that catalyst activity is the most important factor. If the catalyst has a high probability of failing after 1mm growth, the CNTs grown will be short. Optimising the conditions to reduce the...

Nanocrystals slither through tiny tubes Nothing can squeeze through tight spaces quite like a nanocrystal. Physicists watched a small iron crystal slide through a tube with an opening less than half the diameter of the crystal itself. The finding could lead to remotely controlled nanomachines that navigate through confined quarters. Using an electric field, the researchers drove an iron crystal 12 nanometers in diameter through a carbon nanotube like a train in a tunnel. The surprise came when the tube constricted to 5 nanometers in diameter: The iron nanocrystal altered its shape and squeezed through. Microscope images showed that the...

Paper has been getting beat by electronics for years. But it may be about to stage a comeback. Researchers are reporting that they've made batteries and other energy-storage devices by printing layers of carbon nanotube–based ink atop standard photocopy paper. The result is a highly conductive sheet that can carry a charge and be easily incorporated into a flexible battery. Because of paper's low cost, that could help lower the price of batteries used in electric vehicles, wind farms, and other renewable sources. The idea of using paper to make a lightweight, flexible battery isn't new. Researchers led by Robert...

In a remarkable home movie, an international team of researchers has filmed individual metal atoms as they move around and react within the confines of a carbon nanotube. As well as demonstrating the power of the imaging technique, the work has shown that the interior of carbon nanotubes may not be as inert as previously assumed.Andrey Chuvilin from the University of Ulm in Germany and colleagues trapped single atoms of the heavy metal dysprosium within hollow fullerene spheres made up of 82 carbon atoms, and enclosed a series of these dysprosium-seeded cages within single-walled carbon nanotubes, with the fullerenes stringing themselves along the...

Carbon nanotubes are increasingly being used in everyday products such as sporting equipment, biomedical devices and aeroplanes. But questions remain as to how safe these nanotubes really are. A main factor in nanotube toxicity are the metal contaminants that remain from manufacture, which are typically one to ten per cent by weight, say Martin Pumera and Yuji Miyahara at the National Institute for Materials Science, Ibaraki, Japan. 'Carbon nanotubes are often viewed as homogenous materials, which is of course incorrect - they often contain impurities which are not even listed by the manufacturers,'  says Pumera.  The pair have used an electrochemical...

Mini X-ray tubes could revolutionize radiotherapy — and airport baggage scanners. Carbon nanotubes can be used to generate X-rays.Pasieka / Science Photo Library It's taken more than a century, but X-rays are finally getting a shake-up. A new way of generating them uses carbon nanotubes and could allow real-time three-dimensional scanning. "If you look at current imaging technology, technically very little has changed since Wilhelm Röntgen discovered X-rays more than 100 years ago," says materials scientist Otto Zhou at the University of North Carolina (UNC) in Chapel Hill. Zhou and his colleagues first came up with their novel alternative to...

Confusion over classification of nanomaterials under the Reach chemicals legislation has led to two groups of companies using different criteria to submit data on carbon nanotubes to the European Chemicals Agency (ECHA). Currently there is so much uncertainty about dealing with nanomaterials under the Reach regulations (which came into force in 2008) that different groups of companies are forming separate data-gathering bodies, called substance information exchange forums (SIEFs), to deal with carbon nanotubes (CNTs).  One group is setting up its own SIEF for carbon nanotubes to register them as distinct chemicals with their own safety profile. Another much larger collection of CNT...

The nanotube aerogel can expand and contract up to 1,000 times a second.Science Technology Education Media As light as air, yet stronger than steel and bendier than rubber. A new material made from bundles of carbon nanotubes combines all of these characteristics in a substance that twitches like a bionic man's biceps when a voltage is applied.The 'artificial muscle' is an aerogel — a lightweight, sponge-like material consisting mostly of air — drawn into a long ribbon.Applying a voltage across the width of the ribbon electrically charges the nanotubes that thread through the material. This makes them repel one another,...

Nanotubes (above) were used to introduce a complex of proteins into testicular cells (stained, below).UNIDYMA Californian biotech company claims that it has used carbon nanotubes to ‘reprogramme’ adult human cells to an embryonic-like state — a breakthrough that removes the elevated risk of cancer that blights other techniques. But uncertainties about the cells, which have yet to be reported in a peer-reviewed journal, have left many sceptical. PRIMEGEN Last year, researchers led by Shinya Yamanaka of Kyoto University demonstrated that by using just four genes it was possible to reprogramme adult human skin cells to a stem-cell-like pluripotent state —...

A new type of carbon fibre, developed at the University of Cambridge, could be woven into super-strong body armour for the military and law enforcement. The researchers say their material is already several times stronger, tougher and stiffer than fibres currently used to make protective armour. The lightweight fibre, made up of millions of tiny carbon nanotubes, is starting to reveal exciting properties. Carbon nanotubes are hollow cylinders of carbon just one atom thick. The new material was developed by a group at the Department of Materials Science and Metallurgy at Cambridge. It has emerged from efforts to create the...

NASA has begun work on a protein sensor based on carbon nanotubes. “We are working on proteins and have some preliminary data,” Dr. Jun Li of NASA’s Ames Research Center told Electronics Weekly. The design is based on a structure that the organization has been using for DNA sensing. “The bio-sensor is basically an electrochemical sensor,” said Li. “The innovation is in how to constrain a local electrode to optimize sensitivity.”

Since their discovery 14 years ago, carbon nanotubes have captured the imagination of scientists and lay people alike. These structures, so minuscule they cannot be seen, are stronger than diamonds. They are formed from organic material but act as metals or semi-conductors. And they offer great potential in electronics, lasers and medicine. To highlight the current status of nanotube research, Slava V. Rotkin and Shekhar Subramoney have edited a new book, “Applied Physics of Carbon Nanotubes: Fundamentals of Theory, Optics and Transport Devices,” which was just released by Springer. The book's 12 chapters are written by top researchers in the...

Tiny nanotubes are big news in science. Now a research group headed by Dr. Ernesto Joselevich of the Weizmann Institute of Science has developed a new approach to create patterns of carbon nanotubes by having them form along atomic steps on sapphire surfaces. "The orientation and form of the atomic steps on a crystal surface can be controlled by the cutting process, and defects can be created artificially," says Joselevich. "It should thus be possible to produce different nanowire arrangements in a controlled fashion."