which the nanoribbons are pulled apart. The way atoms line up along the edge of a ribbon of graphenehe atom-thick form of carbonontrols
which appeared this month in the Royal Society of Chemistry journal Nanoscale, the Rice team used sophisticated computer modeling to show it's possible to rip nanoribbons
and get graphene with either pristine zigzag edges or what are called reconstructed zigzags. Perfect graphene looks like chicken wire,
The researchers have used the technique to determine that materials with a highly organized structure at the nanoscale are not more efficient at creating free electrons than poorly organized structures#a finding
The researchers created highly organized nanostructures within a portion of the active layer of an organic solar cell meaning that the molecules in that portion all ran the same way.
and it tells us that we don't need highly ordered nanostructures for efficient free electron generation.
and nanostructure features are needed to advance organic solar cell technology. Explore further: Hybrid materials could smash the solar efficiency ceiling More information:
#Researchers generate tiny images that contain over 300 colors A scheme for greatly increasing the number of colors that can be produced by arrays of tiny aluminum nanodisks has been demonstrated by A*STAR scientists.
A similar effect can be realized at a much smaller scale by using arrays of metallic nanostructures since light of certain wavelengths excites collective oscillations of free electrons known as plasmon resonances in such structures.
An advantage of using metal nanostructures rather than inks is that it is possible to enhance the resolution of color images by a hundred fold.
Joel Yang and Shawn Tan at the A*STAR Institute of Materials Research and Engineering and co-workers used an electron beam to form arrays of approximately 100-nanometer-tall pillars.
In these arrays each pixel was an 800-nanometer-long square containing four aluminum nanodisks.
The plasmon resonance wavelength varies sensitively with the dimensions of the nanostructures. Consequently by varying the diameter of the four aluminum nanodisks in a pixel (all four nanodisks having the same diameter) the scientists were able to produce about 15 distinct colors#a good start
but hardly enough to faithfully reproduce full-color images. By allowing two pairs of diametrically opposite nanodisks to have different diameters from each other then varying the two diameters enabled them to increase this number to over 100.
Finally they generated over 300 colors by varying both the nanodisk diameter (but keeping all four diameters within a pixel the same) and the spacing between adjacent nanodisks in a pixel (see image).
This method is analogous to half-toning used in ink-based printing and results in a broad color gamut comments Yang.
The researchers demonstrated the effectiveness of their extended palette using a Monet painting. They reproduced the image using both a limited and extended palette with a much better color reproduction from the extended palette.
Researchers use aluminum nanostructures for photorealistic printing of plasmonic color palettes More information: Tan S. J. Zhang L. Zhu D. Goh X. M. Wang Y. M. et al.
Plasmonic color palettes for photorealistic printing with aluminum nanostructures. Nano Letters 14 4023#4029 (2014.
#One nanoparticle six types of medical imaging It's technology so advanced that the machine capable of using it doesn't yet exist.
University at Buffalo researchers and their colleagues have designed a nanoparticle that can be detected by six medical imaging techniques:
In the future, patients could receive a single injection of the nanoparticles to have all six types of imaging done.
"This nanoparticle may open the door for new'hypermodal'imaging systems that allow a lot of new information to be obtained using just one contrast agent,
"When Lovell and colleagues used the nanoparticles to examine the lymph nodes of mice, they found that CT
One nanoparticle, 6 types of medical imaging This transmission electron microscopy image shows the nanoparticles, which consist of a core that glows blue
The research, Hexamodal Imaging with Porphyrin-Phospholipid-Coated Upconversion Nanoparticles, was published online Jan 14 in the journal Advanced Materials.
The researchers designed the nanoparticles from two components: An"upconversion"core that glows blue when struck by near-infrared light,
"Combining these two biocompatible components into a single nanoparticle could give tomorrow's doctors a powerful,
whether the nanoparticle is safe to use for such purposes, but it does not contain toxic metals such as cadmium that are known to pose potential risks
and found in some other nanoparticles.""""Another advantage of this core/shell imaging contrast agent is that it could enable biomedical imaging at multiple scales, from single-molecule to cell imaging,
and nanoscale lateral dimensions represent two critical capabilities for advanced applications. The thickness can be controlled through a combination of printing parameters including the size of the nozzle the stage speed ink composition and voltage bias.
Their work on high-resolution patterns of quantum dots is of interest as it shows that advanced techniques in e-jet printing offer powerful capabilities in patterning quantum dot materials from solution inks over large areas.
E-jet printing refers to a technique called electrohydrodynamic jet described as a micro/nanomanufacturing process that uses an electric field to induce fluid jet printing through micro/nanoscale nozzles.
Writing in IEEE Spectrum on Monday Prachi Patel similarly made note that Quantum dots (QDS) are light-emitting semiconductor nanocrystals that used in light-emitting diodes (LEDS) hold the promise of brighter faster displays.
Princeton team explores 3d printed quantum dot LEDS More information: High-resolution Patterns of Quantum dots Formed by Electrohydrodynamic Jet Printing for Light-emitting diodes Nano Lett.
#Nanoparticles for clean drinking water One way of removing harmful nitrate from drinking water is to catalyse its conversion to nitrogen.
By using palladium nanoparticles as a catalyst, and by carefully controlling their size, this drawback can be eliminated partially.
It was research conducted by Yingnan Zhao of the University of Twente's MESA+Institute for Nanotechnology that led to this discovery.
Yingnan Zhao decided to use nanometre-sized colloidal palladium particles, as their dimensions can be controlled easily.
This has resulted in palladium nanoparticles that can catalyse the conversion to nitrogen while producing very little ammonia.
which is entitled"Colloidal Nanoparticles as Catalysts and Catalyst Precursors for Nitrite Hydrogenation"on Thursday 15 january a
New nanotechnology keeps bacteria from sticking to surfaces Just as the invention of nonstick pans was a boon for chefs,
a new type of nanoscale surface that bacteria can't stick to holds promise for applications in the food processing, medical and even shipping industries.
The technology, developed collaboratively by researchers from Cornell University and Rensselaer Polytechnic institute, uses an electrochemical process called anodization to create nanoscale pores that change the electrical charge and surface energy of a metal surface,
These pores can be as small as 15 nanometers; a sheet of paper is about 100,000 nanometers thick.
When the anodization process was applied to aluminum, it created a nanoporous surface called alumina, which proved effective in preventing surrogates of two well-known pathogens, Escherichia coli o157:
The study also investigates how the size of the nanopores changes the repulsive forces on bacteria."
"It's probably one of the lowest-cost possibilities to manufacture a nanostructure on a metallic surface,
#Carbon nanotube finding could lead to flexible electronics with longer battery life University of Wisconsin-Madison materials engineers have made a significant leap toward creating higher-performance electronics with improved battery lifend the ability
the team has reported the highest-performing carbon nanotube transistors ever demonstrated. In addition to paving the way for improved consumer electronics,
000 times better and a conductance that's 100 times better than previous state-of-the-art carbon nanotube transistors."
because metallic nanotube impurities act like copper wires and"short"the device. Researchers have struggled also to control the placement and alignment of nanotubes.
Until now these two challenges have limited the development of high-performance carbon nanotube transistors. Building on more than two decades of carbon nanotube research in the field,
the UW-Madison team drew on cutting-edge technologies that use polymers to selectively sort out the semiconducting nanotubes,
achieving a solution of ultra-high-purity semiconducting carbon nanotubes. Previous techniques to align the nanotubes resulted in less than-desirable packing density,
or how close the nanotubes are to one another when they are assembled in a film. However, the UW-Madison researchers pioneered a new technique,
called floating evaporative self-assembly, or FESA, which they described earlier in 2014 in the ACS journal Langmuir.
In that technique, researchers exploited a self-assembly phenomenon triggered by rapidly evaporating a carbon nanotube solution.
The team's most recent advance also brings the field closer to realizing carbon nanotube transistors as a feasible replacement for silicon transistors in computer chips and in high-frequency communication devices,
which are rapidly approaching their physical scaling and performance limits.""This is not an incremental improvement in performance,
"With these results, we've really made a leap in carbon nanotube transistors. Our carbon nanotube transistors are an order of magnitude better in conductance than the best thin film transistor technologies currently being used commercially
while still switching on and off like a transistor is supposed to function.""The researchers have patented their technology through the Wisconsin Alumni Research Foundation
and the Centre for Materials Physics (CSIC-UPV/EHU) has managed with atomic precision to create nanostructures combining graphene ribbons of varying widths.
The work is being published in the prestigious journal Nature Nanotechnology. Few materials have received as much attention from the scientific world
That is why ribbons or rows of graphene with nanometric widths are emerging as tremendously interesting electronic components.
On the other hand due to the great variability of electronic properties upon minimal changes in the structure of these nanoribbons exact control on an atomic level is an indispensable requirement to make the most of all their potential.
The lithographic techniques used in conventional nanotechnology do not yet have such resolution and precision. In the year 2010 however a way was found to synthesise nanoribbons with atomic precision by means of the so-called molecular self-assembly.
Molecules designed for this purpose are deposited onto a surface in such a way that they react with each other
This work the results of which are being published this very week in the prestigious journal Nature Nanotechnology
Manipulating nanoribbons at the molecular level More information: Bandgap Engineering of Bottom-up Synthesized Graphene nanoribbons by Controlled Heterojunctions.
F. Crommie Nature Nanotechnology (2015) DOI: 10.1038/nnano. 2014.307 7
#A speedy test for bladder cancer A fast and accurate urine test for bladder cancer developed by A*STAR researchers has the potential to replace the currently used invasive physical probe.
and bimetallic film over nanoparticles, a planar substrate for enhancing SERS signals. Together these technologies help to overcome interfering signals from the matrix background such as proteins in urine.
The bimetallic film over nanoparticles is coated also with osmium carbonyl clusters to which target-seeking antibodies can be conjugated for assaying A1at (see image).
The researchers first tested the immunoassay on a series of standard solutions containing A1at antigens at various concentrations in the range 10 to 1, 000 nanograms per milliliter.
#Researchers find exposure to nanoparticles may threaten heart health Nanoparticles extremely tiny particles measured in billionths of a meter are increasingly everywhere and especially in biomedical products.
but now a team of Israeli scientists has for the first time found that exposure nanoparticles (NPS) of silicon dioxide (Sio2) can play a major role in the development of cardiovascular diseases
and the Center of Excellence in Exposure Science and Environmental Health (TCEEH Environmental exposure to nanoparticles is becoming unavoidable due to the rapid expansion of nanotechnology says the study's lead author Prof.
and dispose of nanoparticles. Products that use silica-based nanoparticles for biomedical uses such as various chips drug or gene delivery and tracking imaging ultrasound therapy and diagnostics may also pose an increased cardiovascular
risk for consumers as well. In this study researchers exposed cultured laboratory mouse cells resembling the arterial wall cells to NPS of silicon dioxide
The aims of our study were to gain additional insight into the cardiovascular risk associated with silicon dioxide nanoparticle exposure
We also wanted to use nanoparticles as a model for ultrafine particle (UFP) exposure as cardiovascular disease risk factors.
Here researchers have discovered for the first time that the toxicity of silicon dioxide nanoparticles has a significant and substantial effect on the accumulation of triglycerides in the macrophages at all exposure concentrations analyzed
This reality leads to increased human exposure and interaction of silica-based nanoparticles with biological systems.
and environmental hazards are being addressed at the same time as the nanotechnology is being developed. Explore further: New driver of atherosclerosis offers potential as therapeutic targe r
if nanometer-sized carbon balls are added. This could result in enormous efficiency gains in the power grids of the future,
a nanomaterial in the fullerene molecular group, provide strong protection against breakdown of the insulation plastic used in high-voltage cables.
It is sufficient to add very small amounts of fullerene to the insulation plastic for it to withstand a voltage that is 26 per cent higher, without the material breaking down,
Fullerenes prevent electrical trees from forming by capturing electrons that would otherwise destroy chemical bonds in the plastic.
In recent years, other researchers have experimented with fullerenes in the electrically conductive parts of high-voltage cables.
Lina Bertling The Chalmers researchers have demonstrated now that fullerenes are the best voltage stabilizers identified for insulation plastic thus far.
Fullerenes turned out to be the type of additive that most effectively protects the insulation plastic.
#Arming nanoparticles for cancer diagnosis and treatment UCD researchers have manipulated successfully nanoparticles to target two human breast cancer cell lines as a tool in cancer diagnosis and treatment.
Coating nanoparticles with different substances allows their interaction with cells to be tuned in a particular way.
For example using an optically active particle like gold (Au) will provide excellent contrast in near infrared (NIR) imaging
and Chemical Biology and Professor Walter Kolch in Systems Biology Ireland synthesised nanorods with a long iron segment coated with polyethylene glycol
The team believe that Fe-Au functionalised nanorods used in conjunction with these drugs could be useful in cancer treatment.
After characterising and tuning the interaction of the nanorods with the cells the research team assessed how the cells respond to mechanical stimulation.
and used a novel microfluidic chip to monitor the interaction of individual nanorods with two human breast cancer cell lines that express the Erbb family of receptors at different rates.
When the HRG-nanorods bind to cancer cells expressing Erbb they kick off a cascade of signalling events that lead to cell death.
The results are a positive indication for nanoscale targeting and localised manipulation of cancer cells with a specific receptor profile.
#'Trojan horse'proteins are step forward for nanoparticle-based anticancer and anti-dementia therapeutic approaches Scientists at Brunel University London have found a way of targeting hard-to-reach cancers
and degenerative diseases using nanoparticles but without causing the damaging side effects the treatment normally brings.
In a huge step forward in the use of nanomedicine the research helped discover proteins in the blood that disguise nanoparticles
Two studies Complement activation by carbon nanotubes and its influence on the phagocytosis and cytokine response by macrophages and Complement deposition on nanoparticles can modulate immune responses by macrophage B
and T cells found that carbon nanotubes (CNTS) triggered a chain reaction in the complement system which is part of the innate immune system
The interaction between CNTS and C1q (a starter-protein for complement) was anti-inflammatory. This suggests that either coating nanoparticles
or healthy tissue with complement proteins could reduce tissue damage and help treat inflammatory diseases like Parkinson's Huntington's ALS and Alzheimer's.
if the binding between complement proteins and CNTS was direct or indirect. However changing the surfaces of CNTS affected how likely the complement system was to be activated and in what way.
Using the data from this study carbon nanoparticles coated with genetically-engineered proteins are being used to target glioblastoma the most aggressive form of brain tumour.
Dr Uday Kishore from Brunel University London's College of Health and Life sciences said: By using a protein recognised by the immune system to effectively disguise carbon nanoparticles we will be able to deploy these tiny particles to target hard-to-reach areas without damaging side effects to the patient.
This is a big step forward. It is like understanding how to use penicillin safely and could be as revolutionary to modern medicine as its twentieth century predecessor r
#Scalable growth of high quality bismuth nanowires Bismuth nanowires have intriguing electronic and energy harvesting application possibilities.
A group at the CFN Brookhaven National Laboratory has demonstrated a new technique to produce single-crystal nanowires atop arbitrary substrates including glass silicon
#The simplicity of the technique and the universality of the mechanism open a new avenue for the growth of nanowire arrays of a variety of materials.
This is the first report on the high yield(>70%)synthesis of single crystalline bismuth nanowires a material with potentially exploitable and intriguing thermoelectric properties.#
#This technique produces bismuth nanowires in quantities limited only by the size of the substrate on
#The dimensions of the bismuth nanowires can be tuned over a very wide range simply by varying the substrate's temperature.#
#Further in contrast with other fabrication methods with this new technique there is no need for a catalyst to activate the production of the nanowires
CFN's Materials Synthesis and Characterization Electron microscopy and Advanced UV and X-ray Probes Facilities were used for synthesis of nanowires and their structural characterization.
Uniform nanowire arrays for science and manufacturing More information: Surface energy induced formation of single crystalline bismuth nanowires over vanadium thin film at room temperature.
Nano Letters 14 5630#5635 (2014) DOI: 10.1021/nl502208 2
#New'electronic skin'for prosthetics robotics detects pressure from different directions Touch can be a subtle sense,
We used the quantum dots also known as nanoparticles as an ink Mcalpine said. We were able to generate two different colors orange and green.
For example it is not trivial to pattern a thin and uniform coating of nanoparticles and polymers without the involvement of conventional microfabrication techniques yet the thickness and uniformity of the printed films are two of the critical parameters that determine the performance
#Nanotechnology against malaria parasites Malaria parasites invade human red blood cells they then disrupt them and infect others. Researchers at the University of Basel and The swiss Tropical and Public health Institute have developed now so-called nanomimics of host cell membranes that trick the parasites.
#New technique allows low-cost creation of 3-D nanostructures Researchers from North carolina State university have developed a new lithography technique that uses nanoscale spheres to create three-dimensional (3-D) structures
Our approach reduces the cost of nanolithography to the point where it could be done in your garage says Dr. Chih-Hao Chang an assistant professor of mechanical and aerospace engineering at NC State and senior author of a paper on the work.
The NC State researchers took a different approach placing nanoscale polystyrene spheres on the surface of the photosensitive film.
The nanospheres are transparent but bend and scatter the light that passes through them in predictable ways according to the angle that the light takes when it hits the nanosphere.
The researchers control the nanolithography by altering the size of the nanosphere the duration of light exposures and the angle wavelength and polarization of light.
The researchers can also use one beam of light or multiple beams of light allowing them to create a wide variety of nanostructure designs.
We are using the nanosphere to shape the pattern of light which gives us the ability to shape the resulting nanostructure in three dimensions without using the expensive equipment required by conventional techniques Chang says.
And it allows us to create 3-D structures all at once without having to make layer after layer of 2-D patterns.
The researchers have shown also that they can get the nanospheres to self-assemble in a regularly-spaced array
which in turn can be used to create a uniform pattern of 3-D nanostructures. This could be used to create an array of nanoneedles for use in drug delivery
or other applications says Xu Zhang a Ph d. student in Chang's lab and lead author of the paper.
The new technique could also be used to create nanoscale inkjet printers for printing electronics or biological cells or to create antennas or photonic components.
For this work we focused on creating nanostructures using photosensitive polymers which are used commonly in lithography Zhang says.
But the technique could also be used to create templates for 3-D structures using other materials.
We're exploring the use of nanosphere materials other than polystyrene as well as nanoparticle shapes other than spheres Chang says.
The paper Sculpting Asymmetric Hollow-Core Three-dimensional Nanostructures Using Colloidal Particles was published online Dec 8 in the journal Small l
#Atomic'mismatch'creates nano'dumbbells'Like snowflakes nanoparticles come in a wide variety of shapes and sizes.
The geometry of a nanoparticle is often as influential as its chemical makeup in determining how it behaves from its catalytic properties to its potential as a semiconductor component.
Thanks to a new study from the U s. Department of energy's (DOE) Argonne National Laboratory researchers are closer to understanding the process by which nanoparticles made of more than one material called heterostructured nanoparticles form.
Heterostructured nanoparticles can be used as catalysts and in advanced energy conversion and storage systems. Typically these nanoparticles are created from tiny seeds of one material on top of
which another material is grown. In this study the Argonne researchers noticed that the differences in the atomic arrangements of the two materials have a big impact on the shape of the resulting nanoparticle.
Before we started this experiment it wasn't entirely clear what's happening at the interface
when one material grows on another said nanoscientist Elena Shevchenko of Argonne Center for Nanoscale Materials a DOE Office of Science user facility.
In this study the researchers observed the formation of a nanoparticle consisting of platinum and gold.
Initially the gold covered the platinum seed's surface uniformly creating a type of nanoparticle known as core-shell.
While the lattice mismatch is only fractions of a nanometer the effect accumulates as layer after layer of gold forms on the platinum.
As the gold continues to accumulate on one side of the seed nanoparticle small quantities slide down the side of the nanoparticle like grains of sand rolling down the side of a sand hill creating the dumbbell shape.
This is the first time anyone has been able to study the kinetics of this heterogeneous nucleation process of nanoparticles in real-time under realistic conditions said Argonne physicist Byeongdu Lee.
and the nanoscale which gave us a good view of how the nanoparticles form and transform.
This analysis of nanoparticle formation will help to lay the groundwork for the formation of new materials with different and controllable properties according to Shevchenko.
An article based on the research Heterogeneous nucleation and shape transformation of multicomponent metallic nanostructures appeared in the Nov 2 online issue of Nature Materials s
#Scientists use'smallest possible diamonds'to form ultra-thin nanothreads For the first time scientists have discovered how to produce ultra-thin diamond nanothreads that promise extraordinary properties including strength and stiffness greater than that of today's strongest nanotubes
The team's discovery comes after nearly a century of failed attempts by other labs to compress separate carbon-containing molecules like liquid benzene into an ordered diamond-like nanomaterial.
The nanothread also may be the first member of a new class of diamond-like nanomaterials based on a strong tetrahedral core.
One of our wildest dreams for the nanomaterials we are developing is that they could be used to make the super-strong lightweight cables that would make possible the construction of a space elevator
They have demonstrated for the first time the on-demand emission of electron pairs from a semiconductor quantum dot and verified their subsequent splitting into two separate conductors.
Their results have been published in the current online issue of the renowned journal Nature Nanotechnology. A precise control and manipulation of quantum-mechanical states could pave the way for promising applications such as quantum computers and quantum cryptography.
#Nanoparticle network could bring fast-charging batteries (Phys. org) A new electrode design for lithium-ion batteries has been shown to potentially reduce the charging time from hours to minutes by replacing the conventional graphite electrode with a network of tin-oxide nanoparticles.
The anode consists of an ordered network of interconnected tin oxide nanoparticles that would be practical for commercial manufacture
When tin oxide nanoparticles are heated at 400 degrees Celsius they self-assemble into a network containing pores that allow the material to expand
Without the proper pore size and interconnection between individual tin oxide nanoparticles the battery fails. The research paper was authored by Etacheri;
They describe their nanowire mesh design in the journal ACS Nano. Peidong Yang Bin Liu and colleagues note that harnessing sunlight to split water
The researchers took a page from the paper industry using one of its processes to make a flat mesh out of light-absorbing semiconductor nanowires that
Scientists create multifunctional nanotubes using nontoxic materials A doctoral student in materials science at Technische Universitat Darmstadt is making multifunctional nanotubes of goldith the help of Vitamin c and other harmless substances.
The doctoral student in the research group of Professor Wolfgang Ensinger in the Department of Material Analysis is working on making nanotubes of gold.
The metal on the walls of the channels adopts the shape of nanotubes; the film is dissolved then.
and simple basic chemicals can produce such precise nanostructures"says Münch.""Green meets Nano"is a motto of the researchers at the TU.
Its diameter can be set precisely-down to far less than 100 nanometers. The gold nanotubes are thus several hundred times finer than a human hair.
Their wall thickness depends both on the duration of precipitation and on the gold concentration of the original solution.
the result is-depending on the experimental conditions-a collection of individual nanotubes or an array of hundreds of thousands of interconnected tubes.
"With 1 gram of gold, we could make a nanotube for literally every person on earth."
Ensinger's team has tested already successfully one use of the gold nanotubes: they are suitable for building sensors to measure hydrogen peroxide.
The gold nanotubes conduct electricity especially well due to their one-dimensional structure. In addition, they are relatively long
and are thus more durable than normal nanoparticles.""Nano meets Life"is the second motto of the TU Materials science researchers.
For example, they are thinking about also using the nanotubes to measure blood sugar.""A subcutaneous sensor could save diabetes patients from having to constantly prick their fingers"thinks Ensinger.
Overtext Web Module V3.0 Alpha
Copyright Semantic-Knowledge, 1994-2011