•  12/20/04 Selective coatings create biological sensors from nanotubes

Protein-encapsulated carbon nanotubes that alter their fluorescence in the presence of specific biomolecules could generate many new types of implantable biological sensors. In a paper in the journal Nature Materials, the researchers from UIUC showed the viability of their technique by creating a near-infrared nanoscale sensor that detects glucose.

•  12/10/04 Potential way to store memory in ferroelectric nanostructure

University of Arkansas physicists have discovered a new phase in tiny nanodisks and nanorods that potentially may enable researchers to increase memory storage by more than one thousand fold. This finding also opens a new area in physics to fundamental investigation.

•  11/19/04 Multifunctional multi-wall carbon nanotube yarns

Technologies used to spin wool have been adapted to produce yarns made from multi-wall carbon nanotubes. Baughman's group at the University of Texas at Dallas has achieved a major technological breakthrough that should soon lead to the production of futuristic strong, light and flexible 'smart' clothing materials.

•  11/18/04 H2O assisted synthesis of single-walled carbon nanotubes

Japanese researchers report in Science a breakthrough in nanotube synthesis. By simply adding a little water vapor to a standard CVD nanotube production scheme, they've hit upon a new, highly efficient way to grow nanotubes with carbon purity above 99.98%. They have grown "superdense and vertically aligned nanotube forests" and fabricated "patterned, highly organized intrinsic nanotube structures".

•  11/10/04 Ionic nanocrystals show a quick route to change

Alivisatos group at UC-Berkeley reports in Science that for nanocrystals, the doping process in which one type of positively charged atom, or cation, is exchanged for another, take place at a much faster rate than for crystals of extended size, and is fully reversible, something that is virtually forbidden in micro-sized crystals under the same environmental conditions.

•  11/06/04 Epitaxial growth of InP nanowires on germanium

A team of scientists from Philips Research Laboratories and Delft Univ. of Tech., The Netherlands has grown III-V semiconductor nanowires on Ge and Si substrates. In the Nature Materials article, the scien-tists describe the growth of InP nanowires on Ge substrates. In the meantime, the team has also succeed-ed in growing InP and GaP wires on Si substrates.

•  10/22/04 Graphene Goes Ballistic

Physicists in the UK and Russia have shown that films of carbon only one atom thick might have useful elec-tronic properties. The graphene films prepared by Andre Geim and co-workers at Manchester Univ. and the Institute for Microelectronics Technology in Cherno-golovka can be processed to make transistors and may eventually offer an alternative to silicon for some semiconductor applications.

•  10/17/04 Nanowire devices spot viruses

Charles Lieber's group at Harvard University employed a nanowire field-effect transistor to detect single influ-enza viruses while a research team at Cornell Univer-sity used a nanoelectromechanical device to detect an insect baculovirus. The new methods could be scaled up for applications in medicine or the detection of bio-logical weapons.

•  10/08/04 Nanotubes of VOx shape up for spintronics

Scientists at IBM Research have shown that nano-tubes made of vanadium oxide are magnetic at room temperature. Moreover, the magnetic properties of the nanotubes can be controlled by doping them with electrons or holes. The work could have applications in spintronic devices that exploit the spin of the electron as well as its charge to perform logic opera-tions.

 •  09/16/04 Nanotube oscillator can feel extremely small force

Physicists at Cornell University have used carbon nanotubes to make the first nanometer-sized electro-mechanical resonator capable of detecting extremely small forces. The device, consisting of a single nano-tube suspended between two gold electrodes, can be tuned across a wide range of radio frequencies, and one day might replace bulky power-hungry elements in electronic circuits.

 •  09/12/04 4 cm long individual single-walled carbon nanotube

Researchers working at Los Alamos National Laboratory have recently grown a world record-length 4cm-long SWNT. In addition to uses in lightweight, high-strength applica-tions, these long metallic nanotubes also will enable new types of nano electro-mechanical systems such as micro-electric motors, nanoscale diodes, and nanoconducting cable for wiring micro-electronic devices.

IBM scientists have measured a fundamental magnetic property of a single atom -- the energy required to flip its magnetic orientation. This is the first result by a promising new technique they developed to study the properties of nano-scale magnetic structures that are expected to revolutionize future information technologies. From spintronics to quantum computing, a large number of dramatically new ideas for electronic, computing and data storage devices are emerging to exploit the remarkable properties resulting from the magnetic orientations of electrons and atoms.

In an effort to put more science into the largely trial and error building of nanostructures, physicists at NIST have demonstrated new methods for placing what are typically unruly individual atoms at precise locations on a crystal surface. The advance enables scientists to observe and control, for the first time, the movement of a single atom back and forth between neighboring locations on a crystal and should make it easier to efficiently build nanoscale devices "from the bottom up," atom by atom.

Hongjie Dai's group at Stanford University has come up with a relatively simple technique for making devices based on short single-walled carbon nanotubes. The method, which combines photolithography and shadow evaporation, does not require electron beam lithography.

Scientists have shown that gold nanoparticles can help X-rays kill cancerous cells more effectively in mice. The team hopes to refine the technique so that it will eventually work on humans.

Single-walled carbon nanotubes (SWNTs) can be difficult to process because they are insoluble in most solvents. The addition of surfactants can improve SWNT solubility, but the surfactants tend to poison the outstanding nanotube properties. Smalley's group at Rice Univ. building on previous work in which they showed that SWNTs can dissolve in fuming sulfuric acid, have developed a process for spinning the SWNTs into highly oriented fibers without having to debundle the as-formed nanotubes. They show how the superacids interact with the nanotubes and nanotube bundles to make them soluble.

Rinzler's group at University of Florida reported a simple process for the fabrication of ultrathin, transparent, optically homogeneous, electrically conducting films of pure single-walled carbon nanotubes and the transfer of those films to various substrates. For equivalent sheet resistance, the films exhibit optical transmittance comparable to that of commercial indium tin oxide in the visible spectrum, but far superior transmittance in the technologically relevant 2- to 5-micrometer infrared spectral band. These characteristics indicate broad applicability of the films for electrical coupling in photonic devices. In an example application, the films are used to construct an electric field–activated optical modulator, which constitutes an optical analog to the nanotube-based field effect transistor.

While nanowire devices that can emit light and detect photons are already available, nanowire waveguides have so far proved elusive. Now, scientists at the University of California, Berkeley, and Lawrence Berkeley National Laboratory, both in the US, have used nanoribbons of crystalline oxide to channel light between devices.

Physicists have made a bizarre discovery: the concept of temperature is meaningless in some tiny objects. Although the concept of temperature is known to break down on the scale of individual atoms, research now suggests that it may also fail to apply in rather larger entities, such as carbon nanotubes.

Researchers at the NIST have discovered that the addition of carbon nanotubes to a common commercial polymer, polypropylene, leads to dramatic changes in how the molten polymer flows. This process eliminates a widespread manufacturing headache known as "die-swell" in which polymers swell in undesirable directions when passing through the exit port of an extruder.

Ajayan's group at RPI has devised a simple, easy way to make filters of multi-wall carbon nanotubes that could help generate high-octane gasoline and filter out germs.

Two reports about nanoscale understanding of particles appear in the July 30, 2004 issue of Science. The electronic and optical properties of a material can change on going from bulk materials to the nanoscale.

Emory University scientists have for the first time used a new class of luminescent "quantum dot" nanoparticles in living animals to simultaneously target and image cancerous tumors. The quantum dots were encapsulated in a highly protective polymer coating and attached to a monoclonal antibody that guided them to prostate tumor sites in living mice, where they were visible using a simple mercury lamp. The scientists believe the ability to both target and image cells in vivo represents a significant step in the quest to eventually use nanotechnology to target, image, and treat cancer, cardiovascular plaques, and neurodegenerative disease in humans. 

A UK government report said nanotechnology brings great potential but also risks.

A significant breakthrough in the development of the highly prized semiconductor GaN as a building block for nanotechnology has been achieved by a team of scientists with the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California at Berkeley. For the first time ever, the researchers have been able control the direction in which a gallium nitride nanowire grows.

Would You Like a Bouquet of Nanoflowers?

Diamonds are the hardest known substance. Carbon nanotubes are the strongest. Scientists at the U.S. Department of Energy's Argonne National Laboratory [profile] tried to combine the best of both worlds by creating a composite nanostructure. They wanted to grow tiny carbon tubes with tiny diamonds. But the results were not as expected.Instead, the experiment altered the surface area of the nanotubes, creating wing-like extensions. It provides insight into how to synthesize an emerging class of material called “nanocarbons”.

Scientists at Lawrence Berkeley National Laboratory have found new ways of combining quantum dots and segmented nanorods into multiply branching forms and have applied new ways to calculate the electronic properties of these nanostructures.

Researchers at Lund University in Sweden have imaged the inside of a freestanding nanowire with atomic resolution for the first time. The process revealed defects inside a gallium arsenide (GaAs) nanowire such as planar twin segments and single-atom impurities.

Until now, making contact to nanowires and nanotubes in electronic devices has meant using lithography to define metal electrodes. But this means that the contacts must be relatively large. Now, Lieber's group at Harvard University has come up with an integrated contact and interconnection method that overcomes this inherent size constraint. The technique transforms selected regions of silicon nanowires into metallic nickel silicide.

Fascinated by the ship-in-a-bottle trick and other 3-D puzzles? Then here’s one to consider: How do you put a chain inside of a tube and insert the tube into another tube, when the opening of the largest piece measures barely more than one billionth of a meter across?

Researchers from the University of Manchester, UK, and the Italian National Agency for New Technologies, Energy and the Environment (ENEA) have dispersed single- and multi-walled nanotubes in liquid crystals in order to control the alignment of the tubes. The liquid crystal-nanotube dispersions could have applications in externally controlled nanotube switches or in sensor devices.

An amphiphilic hexa-peri-hexabenzocoronene self-assembles to form a -electronic, discrete nanotubular object. The object is characterized by an aspect ratio greater than 1000 and has a uniform, 14-nanometer-wide, open-ended hollow space, which is an order of magnitude larger than those of carbon nanotubes. The wall is 3 nanometers thick and consists of helical arrays of the -stacked graphene molecule, whose exterior and interior surfaces are covered by hydrophilic triethylene glycol chains. The graphitic nanotube is redox active, and a single piece of the nanotube across 180-nanometer-gap electrodes shows, upon oxidation, an electrical conductivity of 2.5 megohms at 285 K. This family of molecularly engineered graphite with a one-dimensional tubular shape and a chemically accessible surface constitutes an important step toward molecular electronics.

Someday, carbon could light up your house. Researchers at China's Tsinghua University and at Louisiana State University have developed a prototype lightbulb that replaces the standard tungsten filament in lightbulbs with a carbon nanotube.

Scientists from the Chinese University of Hong Kong and the University of Oxford, UK, have found that they could induce the self-assembly of multiple nanolayers of zinc oxide (ZnO) and amorphous carbon on the surface of zinc nanowires. The structures could have applications in improving the properties of nanowires.

By threading a magnetic field through a carbon nanotube, scientists have switched the molecule between metallic and semiconducting states, a phenomenon predicted by physicists some years ago, but never before clearly seen in individual molecules. In the May 21 issue of the journal Science, researchers from the Rice Univ. present experimental evidence that a nanotube's electronic structure can be altered in response to a magnetic field.

A researcher from the Institute of Materials Research and Engineering [profile] in Singapore has fashioned a drive shaft that is 1,000 times narrower than a human hair. The component could someday be used in machines that are smaller than bacteria.

Researchers from Meijo University in Japan and Research Centre Jülich in Germany have made what they say is the smallest stable carbon nanotube. The tube, just 3 Angstroms in diameter, grew inside a multiwalled carbon nanotube during a hydrogen arc discharge process.

Senators, Congressmen, entrepreneurs, academics, Nobel-prize winning scientists, and researchers gathered at the National Nanotechnology Initiative (NNI) conference last week (March 31-April 2, 2004) to discuss the state of nanotechnology funding and investment. Currently, most research into the field of nanotechnology is supported by federal or state funding, with states such as California and Texas receiving the lion's share. Most of the speakers at the conference were Government bureaucrats, who explained the nanotechnology related research that their agencies were conducting. The speakers emphasized that the U.S. Government was funding a plethora of molecular research projects, but some implied that more funding of nanotechnology programs would be beneficial.

Tiny "nanotubes" that assemble themselves using the same chemistry as DNA could be ideal for creating better artificial joints and other body implants. Researchers at Purdue University [profile], the University of Alberta and Canada's National Institute for Nanotechnology [profile] have discovered that bone cells called osteoblasts attach better to nanotube-coated titanium than they do to conventional titanium used to make artificial joints.

Researchers at RPI are reporting the discovery of a simple method for rapidly creating different shapes of carbon nanotube structures. To produce the minuscule structures on a commercial scale, manufacturers are looking for such techniques that make it possible to work with materials several billionths of a meter in size.

One key to using nanotubes as the next generation of electronic components is to organize them into patterns more precise than those now possible with conventional lithography. Some form of self-assembly presents an attractive possibility. In organisms, DNA and RNA organize molecules, so it seems logical to try to use DNA to organize nanotubes. A team at the Technion- Israel Institute of Technology has done just that, creating single-nanotube transistors by guiding the nanotubes in a solution into place with DNA.

A method to continuously spin carbon nanotubes has been developed by Cambridge-MIT Institute scientists. Carbon nanotubes have been spun before, but directly spinning them into a fiber as they are made has proven very difficult. The Cambridge way brings the industrial production of a myriad of materials made of carbon nanotubes a step closer.

Researchers at the University of Cambridge, UK, have spun fibres and ribbons of carbon nanotubes directly from the reaction zone of a furnace. They were able to wind up continuous fibre “without apparent limit to length”.

"Nanorings" are the newest members of a growing family of nanometer-scale structures based on single crystals of zinc oxide (ZnO), a semiconducting and piezoelectric material. The rings, complete circles formed by a spontaneous self-coiling process (Figure ), could serve as nanometer-scale sensors, resonators and transducers — and provide a unique test bed for studying piezoelectric effects and other phenomena at the small scale.

Scientists from the University of Maryland, Rowan University, Virginia Tech and Pennsylvania State University, US, have made a nanostructured BaTiO₃-CoFe₂O₄ ferroelectromagnet. The self-assembled multiferroic structure contained vertical CoFe₂O₄ nanopillars in a ferroelectric BaTiO₃ matrix.

Researchers at Rice University have discovered how to create continuous fibers of out of pristine single-walled carbon nanotubes. The process, which is similar to the one used to make Kevlar® on an industrial scale, offers the first real hope of making threads, cables and sheets of pure carbon nanotubes (SWNTs).

For a decade, materials scientists have dreamed of using nanotubes as the building blocks for a new generation of sensors, transistors, and other tiny devices. Before that happens, however, researchers must find better ways to grow and align these carbon nanotubes.Jie Liu and his colleagues at Duke University in Durham, N.C., now report growing the longest individual carbon nanotubes ever and aligning them in a two-dimensional grid.