Articles from February 2013

Solar Energy Cost-Competitive with Fossil Fuels?

A novel fabrication technique developed by the University of ConnecticutUConn could provide the breakthrough technology scientists have been looking for to vastly improve today’s solar energy systems.The technology would be a vast improvement over the silicon solar panels. Even the best silicon panels collect only about 20 percent of available solar radiation, and separate mechanisms are needed to convert the stored energy to usable electricity for the commercial power grid. The panels’ limited efficiency and expensive development costs have been two of the biggest barriers to the widespread adoption of solar power as a practical replacement for traditional fossil fuels.
But while nanosized antennas have shown promise in theory, scientists have lacked the technology required to construct and test them. The fabrication process is immensely challenging. The nano-antennas – known as “rectennas” because of their ability to both absorb and rectify solar energy from alternating current to direct current – must be capable of operating at the speed of visible light and be built in such a way that their core pair of electrodes is a mere 1 or 2 nanometers apart, a distance of approximately one millionth of a millimeter. Nanosized antenna arrays are theoretically capable of harvesting more than 70 percent of the sun’s electromagnetic radiation and simultaneously converting it into usable electric power.
The potential breakthrough lies in a novel fabrication process called selective area atomic layer deposition (ALD) that was developed by Willis, an associate professor of chemical and biomolecular engineering at UConn. Willis developed the ALD process while teaching at the University of Delaware, and patented the technique in 2011.


How To Miniaturize Batteries

While the demand for ever-smaller electronic devices has spurred the miniaturization of a variety of technologies, one area has lagged behind in this downsizing revolution: energy-storage units, such as batteries and capacitors. Now, Richard Kaner, a member of the California NanoSystems Institute at UCLA and a professor of chemistry and biochemistry, and Maher El-Kady, a graduate student in Kaner‘s laboratory, may have changed the game.The UCLA researchers have developed a groundbreaking technique that uses a DVD burner to fabricate micro-scale graphene-based supercapacitors — devices that can charge and discharge a hundred to a thousand times faster than standard batteries. These micro-supercapacitors, made from a one-atom–thick layer of graphitic carbon, can be easily manufactured and readily integrated into small devices such as next-generation pacemakers.The new cost-effective fabrication method, described in a study published this week in the journal Nature Communications, holds promise for the mass production of these supercapacitors, which have the potential to transform electronics .

The integration of energy-storage units with electronic circuits is challenging and often limits the miniaturization of the entire system,” said Kaner,. “This is because the necessary energy-storage components scale down poorly in size and are not well suited to the planar geometries of most integrated fabrication processes.” “Traditional methods for the fabrication of micro-supercapacitors involve labor-intensive lithographic techniques that have proven difficult for building cost-effective devices, thus limiting their commercial application,El-Kady said. “Instead, we used a consumer-grade LightScribe DVD burner to produce graphene micro-supercapacitors over large areas at a fraction of the cost of traditional devices. Using this technique, we have been able to produce more than 100 micro-supercapacitors on a single disc in less than 30 minutes, using inexpensive materials.

Revolutionary Method To Convert Sunlight into Energy

A new method of harvesting the Sun’s energy is emerging, thanks to scientists at UC Santa Barbara‘s Departments of Chemistry, Chemical Engineering, and Materials. Though still in its infancy, the research promises to convert sunlight into energy using a process based on metals that are more robust than many of the semiconductors used in conventional methods.
When nanostructures, such as nanorods, of certain metals are exposed to visible light, the conduction electrons of the metal can be caused to oscillate collectively, absorbing a great deal of the light,” said Martin Moskovits, professor of chemistry at UCSB.. “This excitation is called a surface plasmon.
It is the first radically new and potentially workable alternative to semiconductor-based solar conversion devices to be developed in the past 70 years or so,” said Moskovits.

Catalyst Converts Hydrogen Directly To Electricity

A research team at the Center for Molecular Electrocatalysis – Pacific Northwest National Laboratory (PNNL) has been developing catalysts that use cheaper metals such as nickel and iron to make fuel cells more economical. The one they report here can split hydrogen as fast as two molecules per second with an efficiency approaching those of commercial catalysts. The center is one of 46 Energy Frontier Research Centers established by the DOE Office of Science across USA to accelerate basic research in energy.
hydrogen electric carHyundai ix35 FCEV (Fuel Cell Electric Vehicle)

A drawback with today’s fuel cells is that the platinum they use is more than a thousand times more expensive than iron,” said chemist R. Morris Bullock, who leads the research at the Department of Energy’s Pacific Northwest National Laboratory
such a catalyst is the first iron-based catalyst that converts hydrogen directly to electricity. The result moves chemists and engineers one step closer to widely affordable fuel cells.

Protein Passport to Past Immune System

The body’s immune system exists to identify and destroy foreign objects, whether they are bacteria, viruses, flecks of dirt or splinters. Unfortunately, nanoparticles designed to deliver drugs, and implanted devices like pacemakers or artificial joints, are just as foreign and subject to the same response. Now, researchers at the University of Pennsylvania School of Engineering and Applied Science and Penn’s Institute for Translational Medicine and Therapeutics have figured out a way to provide a “passport” for such therapeutic devices, enabling them to get past the body’s security system.
protein passport

From your body’s perspective,” said the student Rodriguez, member of the research team led by professor Dennis Discher, “an arrowhead a thousand years ago and a pacemaker today are treated the same — as a foreign invader. “We’d really like things like pacemakers, sutures and drug-delivery vehicles to not cause an inflammatory response from the innate immune system.


Nano-Shish-Kebabs for Better Lithium-Ion Batteries

Researchers at North Carolina State University have developed a new type of nanoscale structure that resembles a “nano-shish-kebab,” consisting of multiple two-dimensional nanosheets that appear to be impaled upon a one-dimensional nanowire. However, the nanowire and nanosheets are actually a single, three-dimensional structure consisting of a seamless series of germanium sulfide (GeS) crystals. The structure holds promise for use in the creation of new, three-dimensional (3-D) technologies. The researchers believe this is the first engineered nanomaterial to combine one-dimensional and two-dimensional structures in which all of the components have a shared crystalline structure.
We think this approach could also be used to create heterostructures like these using other materials whose molecules form similar crystalline layers, such as molybdenum sulfide (MoS2),” says Dr. Linyou Cao, an assistant professor of materials science and engineering at NC State and co-author of a paper on the research. “And, while germanium sulfide has excellent photonic properties, MoS2 holds more promise for electronic applications.
For instance it could be used to develop 3-D devices, such as next-generation sensors, photodetectors or solar cells. This 3-D structure could also be useful for developing new energy storage technologies, like Lithium-Ion batteries.


Forging Artificial Atoms

Chad A. Mirkin, a researcher from Northwestern University, has developed a completely new set of building blocks that is based on nanoparticles and DNA. Using these tools, scientists will be able to build — from the bottom up, just as nature does — new and useful structures. Using nanoparticles and DNA, Mirkin has built more than 200 different crystal structures with 17 different particle arrangements. Some of the lattice types can be found in nature, but he also has built new structures that have no naturally occurring mineral counterpart.
artificial atom
We have a new set of building blocks,” Mirkin said. “Instead of taking what nature gives you, we can control every property of the new material we make. We’ve always had this vision of building matter and controlling architecture from the bottom up, and now we’ve shown it can be done.”

Mirkin has presented his research in a session titled “Nucleic Acid-Modified Nanostructures as Programmable Atom Equivalents: Forging a New Periodic Table” at the American Association for the Advancement of Science (AAAS) annual meeting in Boston.

A cell phone charger that recharges your phone remotely

Recharge your phone remotely without even knowing where it is; or a device that targets and destroys tumors, wherever they are in the body; or a security field that can disable electronics, even a listening device hiding in a prosthetic toe, without knowing where it is.While these applications remain only dreams, researchers at the University of Maryland have come up with a sci-fi seeming technology that one day could make them real. Using a “time-reversal” technique, the team has discovered how to transmit power, sound or images to a “nonlinear object” without knowing the object’s exact location or affecting objects around it.

time reversal

That’s the magic of time reversal,” says Steven Anlage, a university physics professor involved in the project. “When you reverse the waveform’s direction in space and time, it follows the same path it took coming out and finds its way exactly back to the source.

Physical Review Letters:

Nano-machines for “Bionic Proteins”

Physicists of the University of Vienna together with researchers from the University of Natural Resources and Life Sciences Vienna developed nano-machines which recreate principal activities of proteins. They present the first versatile and modular example of a fully artificial protein-mimetic model system, thanks to the Vienna Scientific Cluster (VSC), a high performance computing infrastructure. These “bionic proteins” could play an important role in innovating pharmaceutical research. The results have now been published in the journal “Physical Review Letters“.
bionic protein
Proteins are the fundamental building blocks of all living organism we currently know. Because of the large number and complexity of bio-molecular processes they are capable of, proteins are often referred to as “molecular machines“. Take for instance the proteins in your muscles: At each contraction stimulated by the brain, an uncountable number of proteins change their structures to create the collective motion of the contraction. This extraordinary process is performed by molecules which have a size of only about a nanometer, a billionth of a meter. Muscle contraction is just one of the numerous activities of proteins: There are proteins that transport cargo in the cells, proteins that construct other proteins, there are even cages in which proteins that “mis-behave” can be trapped for correction, and the list goes on and on. “Imitating these astonishing bio-mechanical properties of proteins and transferring them to a fully artificial system is our long term objective“, says Ivan Coluzza from the Faculty of Physics of the University of Vienna, who works on this project together with colleagues of the University of Natural Resources and Life Sciences Vienna.


Ultra-sensitive Tool for DNA analysis, thanks to Ancient Roman Cup

Utilizing optical characteristics first demonstrated by the ancient Romans, researchers at the University of Illinois at Urbana-Champaign have created a novel, ultra-sensitive tool for chemical, DNA, and protein analysis..plasmon resonance sensor
With this device, the nanoplasmonic spectroscopy sensing, for the first time, becomes colorimetric sensing, requiring only naked eyes or ordinary visible color photography,” explained Logan Liu, an assistant professor of electrical and computer engineering and of bioengineering at Illinois. “It can be used for chemical imaging, biomolecular imaging, and integration to portable microfluidics devices for lab-on-chip-applications“. His research team’s results were featured in the cover article of the inaugural edition of Advanced Optical Materials (AOM, optical section of Advanced Materials).

Roman Cup
Lycurgus cups were created by the Romans in 400 A.D. Made of a dichroic glass, the famous cup exhibits different colors depending on whether or not light is passing through it; red when lit from behind and green when lit from in front. It is also the origin of inspiration for all contemporary nanoplasmonics research—the study of optical phenomena in the nanoscale vicinity of metal surfaces.

Nanotechnology Used To Prevent Hay Fever

Scientists at the Charité – Universitätsmedizin Berlin – Germany – have now been able to identify the grass pollen molecule, against which the allergic response of hay fever in children is initiated. In addition, it was shown that the first individual antibodies generated in children against individual pollen molecules can be identified even before the initial symptoms of a pollen allergy are developed. The findings of this long-term study have appeared in the Journal of Allergy and Clinical Immunology. In its study, the Molecular Allergology working group headed by Adj. Professor Dr. Paolo Matricardi investigated the data and blood samples taken from 820 children. The working group was for the first time also able to examine the data using nanotechnological methods at a molecular level.

The detection of lgE antibodies at an early stage could enhance the prospects of a successful therapeutic and even preventative intervention”, according to a confident Laura Hatzler, the first author of the study. “The investigation of allergen-specific, immunological treatments at early stages of the disease process in childhood represents the next step in our research.


3 times more powerfull Lithium-Ion Batteries, recharge in 10 minutes

Researchers at the University of South California – USC have developed a new lithium-ion battery design that uses porous silicon nanoparticles in place of the traditional graphite anodes to provide superior performance. The new batteries—which could be used in anything from cell phones to hybrid cars—hold three times as much energy as comparable graphite-based designs and recharge within 10 minutes. The design, currently under a provisional patent, could be commercially available within two to three years.

It’s an exciting research. It opens the door for the design of the next generation lithium-ion batteries,” said Chongwu Zhou, professor at the USC Viterbi School of Engineering, who led the team that developed the battery. Zhou worked with USC graduate students Mingyuan Ge, Jipeng Rong, Xin Fang and Anyi Zhang, as well as Yunhao Lu of Zhejiang University in China. Their research was published in Nano Research in January. “The easy method we use may generate real impact on battery applications in the near future,” Zhou said.