In physics, there's small, and then there's nullity, as in zero-dimensional. Univ. of Cincinnati researchers have reached this threshold with a special structure, zero-dimensional quantum dots, that may someday lead to better ways of harnessing solar energy, stronger lasers or more sensitive medical diagnostic devices.
A big step in the development of advanced fuel cells and water-alkali electrolyzers has been achieved with the discovery of a new class of bimetallic nanocatalysts that are an order of magnitude higher in activity than the target set by the U.S. Department of Energy for 2017. The new catalysts feature a 3-D catalytic surface activity that makes them significantly more efficient and far less expensive than the best platinum catalysts.
Ultraviolet light (UV) has not only harmful effects on molecules and biological tissue like human skin but it also can impair the performance of organic solar cells upon long-term exposure. Researchers in Germany have now developed a so-called plasmonic metamaterial which is compatible with solar technology and completely absorbs UV light despite being only 20 nm thin.
How heat flows at the nanoscale can be very different than at larger scales, and researchers are working to understand how these features affect the transport of the fundamental units of heat, called phonons. At Cornell Univ. scientists have invented a phonon spectrometer whose measurements are 10 times sharper than standard methods. This boosted sensitivity has uncovered never-before-seen effects of phonon transport.
Tear apart an electric car's rechargeable battery and you'll find a mineral normally associated with No. 2 pencils. It's graphite. And experts say the promise of expanded uses for "pencil lead" in lithium-ion batteries, as well as a decrease in supply from China, has helped touch off the largest wave of mining projects in decades.
Cornell Univ. researchers have recently led what is probably the most comprehensive study to date of block copolymer nanoparticle self-assembly processes. The work is important, because using polymers to self-assemble inorganic nanoparticles into porous structures could revolutionize electronics.
Researchers from North Carolina State Univ. have developed a superabsorbing design that may significantly improve the light absorption efficiency of thin-film solar cells and drive down manufacturing costs. The superabsorbing design could decrease the thickness of the semiconductor materials used in thin-film solar cells by more than one order of magnitude without compromising the capability of solar light absorption.
A new study from the International Electrotechnical Commission and the Fraunhofer Institute in Europe has found that nanotechnology will bring significant benefits to the energy sector, especially to energy storage and solar energy. Improved materials efficiency and reduced manufacturing costs are just two of the real economic benefits that nanotechnology already brings these fields and that’s only the beginning.
Every second, your computer must process billions of computational steps to produce even the simplest outputs. Imagine if every one of those steps could be made just a tiny bit more efficient. A Northeastern Univ. team has developed a series of novel devices that do just that. The team combined their expertise to unearth a physical phenomenon that could usher in a new wave of highly efficient electronics.
Researchers at Argonne National Laboratory in collaboration with scientists at Northwestern Univ. are the first to grow graphene on silver which, until now, posed a major challenge to many in the field. Part of the issue has to do with the properties of silver, the other involves the process by which graphene is grown.
Researchers have devised a way of making tiny holes of controllable size in sheets of graphene, a development that could lead to ultra-thin filters for improved desalination or water purification. The team of researchers succeeded in creating subnanoscale pores in a sheet of the one-atom-thick material, which is one of the strongest materials known.
When deciding what materials to use in building something, determining how those materials respond to stress and strain is often the first task. A material’s macroscopic, or bulk, properties in this area is generally the product of what is happening on a microscopic scale. When stress causes a material’s constituent molecules to rearrange in a way such that they can't go back to their original positions, it is known as plastic deformation.
Researchers from NIST and the FDA have demonstrated that they can make sensitive chemical analyses of minute samples of nanoparticles by, essentially, roasting them on top of a quartz crystal. The NIST-developed technique, "microscale thermogravimetric analysis," holds promise for studying nanomaterials in biology and the environment, where sample sizes often are quite small and larger-scale analysis won't work.
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.