To attach itself to surfaces, the marine sponge Monorhaphis chuni forms an unusual glass rod. Researchers have recently analyzed the nanostructure of the filament passing through the center of this glass rod and discovered that it is formed with a perfect periodic arrangement of nanopores. In this way, the sponge employs a similar method that is now used for fabrication of man-made mesoporous nanomaterials.
Previous efforts to create graphene nanoribbons followed a top-down approach, using lithography and etching process to try to cut ribbons out of graphene sheets. Cutting ribbons 2 nm-wide is not practical, however, and these efforts have not been very successful. Now, a research team has developed a chemical approach to mass producing these graphene nanoribbons. This process that may provide an avenue to harnessing graphene's conductivity.
A tabletop device invented at Rice Univ. can tell how efficiently a nanoparticle would travel through a well and may provide a wealth of information for oil and gas producers. The device gathers data on how tracers, microscopic particles that can be pumped into and recovered from wells, move through deep rock formations that have been opened by hydraulic fracturing.
Researchers in the U.K. have developed a method of controlling the composition of a range of polymers, the large molecules that are commonly used as plastics and fibers. They have demonstrated how the chemical reactions can be manipulated, especially in fixing the composition of a polymer using a mixture of up to three different monomers. The secret lies in understanding and switching “on” and “off” the catalyst used to make the polymers.
The scarcity of ultraviolet (UV) light in sunlight has held back the usefulness of titanium dioxide-based photocatalysts. Through the application of nanotechnology, researchers in Japan have recently succeeded in the development of better titanium dioxide-based material that can be activated by visible light. The solution lies in an array of nanoparticles that “simulate” the photoexcitation of UV light.
Univ. of Colorado Boulder scientists have found a creative way to radically improve thermoelectric materials, a finding that could one day lead to the development of improved solar panels and more energy-efficient cooling equipment. The technique, building an array of tiny pillars on top of a sheet of thermoelectric material, represents an entirely new way of attacking a century-old problem.
A multi-university team of engineers has developed what could be a promising solution for charging smartphone batteries on the go, without the need for an electrical cord. Incorporated directly into a cell phone housing, the team's nanogenerator could harvest and convert vibration energy from a surface, such as the passenger seat of a moving vehicle, into power for the phone.
Clemson Univ. researchers have developed nanoparticles that can deliver drugs targeting damaged arteries, a non-invasive method to fight heart disease. Heart disease is the leading cause of death in the U.S., according to the Centers for Disease Control and Prevention. One of the standard ways to treat clogged and damaged arteries currently is to implant vascular stents, which hold the vessels open and release such drugs as paclitaxel.
An electrode designed like a pomegranate—with silicon nanoparticles clustered like seeds in a tough carbon rind—overcomes several remaining obstacles to using silicon for a new generation of lithium-ion batteries, say its inventors at Stanford Univ. and the SLAC National Accelerator Laboratory.
A single-walled carbon nanotube grows from the round cap down, so it’s logical to think the cap’s formation determines what follows. But according to researchers at Rice Univ., that’s not entirely so. Theoretical physicist Boris Yakobson and his Rice colleagues found through exhaustive analysis that those who wish to control the chirality of nanotubes would be wise to look at other aspects of their growth.
On a pound-per-pound basis, carbon nanotube-based fibers invented at Rice Univ. have greater capacity to carry electrical current than copper cables of the same mass, according to new research. While individual nanotubes are capable of transmitting nearly 1,000 times more current than copper, the same tubes coalesced into a fiber using other technologies fail long before reaching that capacity.
A team in France has greatly miniaturized the light-emitting diode (LED) by creating one from a single polythiophene wire placed between the tip of a scanning tunneling microscope and a gold surface. This nanowire, which is made of the same hydrogen, carbon and sulfur components found in much larger LEDs, emits light only when the current passes in a certain direction.
An international partnerships is aiming to develop robust fingerprint sensors with resolution beyond today’s 500 dpi international standards, the minimum required by the U.S. Federal Bureau of Investigation. The new platform uses vertical piezoelectric nanowire matrices designed using multiphysics modeling software.
An international team has recently unveiled a superconducting pairing mechanism in calcium-doped graphene. The pairing, which was using a angle-resolved photoemission spectroscopy method, is important because graphene is easily doped or functionalized with chemicals, allowing scientists to more fully explore the nature of superconductivity.
Engineers are increasingly turning to plasmonic color filters (PCFs) to create and control a broad spectrum of colors for imaging applications. However, PCF light transmission efficiency has been limited to only about 30%, less than half the rate of conventional filters. Researchers have now developed a new PCF scheme that achieves a transmission efficiency of 60 to 70%.
Inspired by tiny particles that carry cholesterol through the body, Massachusetts Institute of Technology chemical engineers have designed nanoparticles that can deliver snippets of genetic material that turn off disease-causing genes. This approach, known as RNA interference, holds great promise for treating cancer and other diseases. However, delivering enough RNA to treat the diseased tissue has proven difficult.
Materials experts in Ireland have developed a new germanium nanowire-based anode that has the ability to greatly increase the capacity and lifetimes of lithium-ion batteries. The typical lithium-ion battery on the market today is based on graphite, which has a relatively low capacity for energy storage. Restructuring the germanium replacement material into nanowires produces a stable, porous battery material.
Cars inch forward slowly in traffic jams, but molecules, when jammed up, can move extremely fast. New research by Northwestern Univ. researchers finds that water molecules traveling through tiny carbon nanotube pipes do not flow continuously but rather intermittently, like stop-and-go traffic, with unexpected results.
An international team of researchers from France and the United States have devised an entirely new way to synthesize graphene ribbons with defined, regular edges, allowing electrons to flow freely through the material. Demonstrating this phenomenon at room temperature, the material was shown to permit electron flow up to 200 times faster than through silicon.
We all learn in high school science about the dual nature of light—that it exists as both waves and quantum particles called photons. It’s this duality of light that enables the coherent transport of photons in lasers. Sound at the atomic-scale has the same dual nature, existing as both waves and quasi-particles known as phonons. Does this duality allow for phonon-based lasers?
Using electrons more like photons could provide the foundation for a new type of electronic device that would capitalize on the ability of graphene to carry electrons with almost no resistance even at room temperature—a property known as ballistic transport. Research reported that electrical resistance in nanoribbons of epitaxial graphene changes in discrete steps following quantum mechanical principles.
Researchers at Tyndall National Institute in Ireland have produced the first ever atom-by-atom simulation of nanoscale film growth by atomic layer deposition (ALD), a thin-film technology used in the production of silicon chips. The accomplishment required the acquisition of the complete set of hundreds of ALD reactions at the quantum mechanical level.
Designing nanomedicine to combat diseases is a hot area of scientific research, primarily for treating cancer, but very little is known in the context of atherosclerotic disease. Scientists have engineered a microchip coated with blood vessel cells to learn more about the conditions under which nanoparticles accumulate in the plaque-filled arteries of patients with atherosclerosis, the underlying cause of myocardial infarction and stroke.
Scientists have used a particle physics theory to describe the behavior of particle-like entities, referred to as excitons, in two layers of graphene. The use of equations typically employed in high-energy physics has prompted the authors to suggest a design for an experimental device relying on a magnetically tunable optical filter that could verify their predictions.
Perfect sheets of diamond a few atoms thick appear to be possible even without the big squeeze that makes natural gems. Scientists have speculated about it and a few laboratories have even seen signs of what they call diamane, an extremely thin film of diamond that has all of diamond’s superior semiconducting and thermal properties.