and carrier concentrations with an accurate nanoscale picture of the semiconductor film's microstructure really gives a complete picture of how the device operates and
#Electron microscopes take first measurements of nanoscale chemistry in action (Phys. org) Scientists'underwater cameras got a boost this summer from the Electron microscopy Center at the U s. Department of energy's Argonne National Laboratory.
Along with colleagues at the University of Manchester researchers captured the world's first real-time images and simultaneous chemical analysis of nanostructures while underwater or in solution.
and materials scientists to explore never-before-measured stages of nanoscale chemical processes in materials said Argonne materials scientist Nestor Zaluzec one of the paper's authors.
Understanding how materials grow at the nanoscale level helps scientists tailor them for everything from batteries to solar cells.
and nanoscale for decades but it's usually done with the sample in a vacuum Zaluzec said.
This lets scientists watch as nanostructures grow and change with time during chemical reactions. The team is now working with the manufacturer Protochips Inc. to make this capability available to the scientific community.
The study Real-time imaging and local elemental analysis of nanostructures in liquids was published in the journal Chemical Communications with researchers from the University of Manchester and BP.
Real-time imaging and local elemental analysis of nanostructures in liquids. Edward A. Lewis et al. Chem.
The researchers used a handheld device resembling a laser pointer that can detect Raman nanoprobes with very high accuracy.
These nanoprobes are injected the day prior to the operation and go specifically to tumor cells and not to normal brain cells.
Guiding Brain tumor Resection Using Surface-Enhanced Raman Scattering Nanoparticles and a Hand-held Raman Scanner ACS Nano Article ASAPDOI:
Here we evaluated the ability of a hand-held Raman scanner guided by surface-enhanced Raman scattering (SERS) nanoparticles to identify the microscopic tumor extent in a genetically engineered RCAS/tv-a glioblastoma mouse model.
and correlation with histology showed that SERS nanoparticles accurately outlined the extent of the tumors.
because it uses inert gold#silica SERS nanoparticles and a hand-held Raman scanner that can guide brain tumor resection in the operating room o
#Ultrafast graphene based photodetectors with data rates up to 50 GBIT/s In cooperation with Alcatel Lucent Bell labs researcher from AMO realized the worldwide fastest Graphene based photodetectors.
Graphene a two-dimensional layer of carbon atoms is currently one of the most promising materials for future ultrafast and compact telecommunication systems.
In the current work Graphene based photodetectors were integrated in a conventional silicon photonic platform designed for future on-chip applications in the area of ultrafast data communication.
In addition the specific features of Graphene-based photodetectors like dark current free and high speed operation
not only set a new benchmark for graphene based photodetectors but also demonstrate for the first time that Graphene based photodetectors surpass comparable detectors based on conventional materials concerning maximal data rates.
The work was supported by the European commission through the Flagship project Graphene and the integrated project Grafol as well as the DPG supported project Gratis.
The publication is published in the international renowned journal ACS Photonics and was chosen as Editor's Choice article.
Graphene and related materials promise cheap flexible printed cameras More information: 50 GBIT/s photodetectors based on wafer-scale graphene for integrated silicon photonic communication systems.
ACS Photonics Just Accepted Manuscript. DOI: 10.1021/ph500160 6
#Graphene reinvents the future For many scientists the discovery of one-atom-thick sheets of graphene is hugely significant something with the potential to affect just about every aspect of human activity and endeavour.
Graphene is hidden inside graphite an ore that has not been particularly sought after in the past. But a few years ago it revealed a secret.
At the molecular level it is a unique two-dimensional molecule: an electrically conductive latticelike layer just one carbon atom thick.
Graphene has usually cautious physicists and chemists itching with excitement mesmerised by the possibilities starting to take shape from flexible electronics embedded into clothing to biomedicine (imagine synthetic nerve cells) vastly superior forms of energy storage (tiny
But despite the extraordinary potential for graphene's properties the stumbling block has been to get it into a useable form.
Professor Li has invented a cost-effective and scalable way to split graphite into microscopic graphene sheets and dissolve them in water.
From this he has developed two new graphene technology platforms the starting points for developing commercial applications. One is a graphene gel that works as a supercapacitor electrode
and the second is a 3-D porous graphene foam. The graphene gel provides the same functionality as porous carbon a material currently sourced from coconut husks for use in supercapacitors and other energy conversion and storage technologies but with vastly enhanced performance.
Supercapacitors have an expanding range of applications as their capabilities increase from powering computer memory backup to powering electric vehicles.
Professor Li's team has also been able to give graphene a more functional 3-D form by engineering it into an elastic graphene foam that retains its extraordinary qualities.
Professor Li likened his developments to having invented bricks and said it was time to bring in architects
a new class of nanoscale materials made in sheets only three atoms thick. The University of Washington researchers have demonstrated that two of these single-layer semiconductor materials can be connected in an atomically seamless fashion known as a heterojunction.
#Competition for graphene: Researchers demonstrate ultrafast charge transfer in new family of 2-D semiconductors A new argument has just been added to the growing case for graphene being bumped off its pedestal as the next big thing in the high-tech world by the two-dimensional semiconductors
known as MX2 materials. An international collaboration of researchers led by a scientist with the U s. Department of energy (DOE)' s Lawrence Berkeley National Laboratory (Berkeley Lab) has reported the first experimental observation of ultrafast charge transfer in photo-excited
"Wang is the corresponding author of a paper in Nature Nanotechnology describing this research. The paper is titled"Ultrafast charge transfer in atomically thin Mos2/WS2 heterostructures."
These 2d semiconductors feature the same hexagonal"honeycombed"structure as graphene and superfast electrical conductance,
but, unlike graphene, they have natural energy band-gaps. This facilitates their application in transistors and other electronic devices because
unlike graphene, their electrical conductance can be switched off.""Combining different MX2 layers together allows one to control their physical properties,
who is also an investigator with the Kavli Energy Nanosciences Institute (Kavli-ENSI).""For example, the combination of Mos2 and WS2 forms a type-II semiconductor that enables fast charge separation.
#Conductive nanofiber networks for flexible unbreakable and transparent electrodes Transparent conductors are required as electrodes in optoelectronic devices, such as touch panel screens, liquid crystal displays, and solar cells.
Tokyo Institute of technology researchers report the first development of a facile method for the fabrication of flexible and unbreakable transparent electrodes using nanofibers.
Two-dimensional aluminum (Al) nanofiber networks offering transparent conductors were fabricated by simple wet chemical etching of Al metalized polymer films using an electrospun polystyrene nanofiber mask template.
The resulting Al nanowire networksith a width of 500 nm and an area fraction of 22.0%xhibited 80%optical transmittance and sheet resistance of 45 O sq-1
The metallic nanostructures use surface plasmons waves of electrons that flow like a fluid across metal surfaces.
Researchers use aluminum nanostructures for photorealistic printing of plasmonic color palettes More information: Zheng B. Y. Wang Y. Nordlander P. and Halas N. J. 2014) Color-Selective and CMOS-Compatible Photodetection Based on Aluminum Plasmonics.
#Scientists fabricate defect-free graphene set record reversible capacity for Co3o4 anode in Li-ion batteries Graphene has already been demonstrated to be useful in Li-ion batteries,
despite the fact that the graphene used often contains defects. Large-scale fabrication of graphene that is chemically pure, structurally uniform,
and size-tunable for battery applications has remained so far elusive. Now in a new study, scientists have developed a method to fabricate defect-free graphene (df-G) without any trace of structural damage.
Wrapping a large sheet of negatively charged df-G around a positively charged Co3o4 creates a very promising anode for high-performance Li-ion batteries.
current methods to fabricate high-quality graphene fall into two categories: mechanical approaches and chemical approaches. While mechanical cleavage provides high-quality graphene,
its low yield makes it insufficient for large-scale production. Chemical approaches, on the other hand, can produce bulk quantities
which causes the layers to expand away from each other to form graphene nanosheets that could later be cooled
because when a single graphene sheet is wrapped around a bundle of Co3o4 particles, the Co3o4 particles are prevented from becoming pulverized
whereas anodes with an imperfect graphene layer rapidly decrease with cycling. The large size of the graphene plays a key role in the performance
because a larger size provides a higher cycling stability of the nanosized anode materials by improving their mechanical integrity.
but a new way of working with copper nanowires and a PVA"nano glue"could be a game-changer.
Previous success in the field of ultra-lightweight"aerogel monoliths"has relied largely on the use of precious gold and silver nanowires.
By turning instead to copper, both abundant and cheap, researchers at Monash University and the Melbourne Centre for Nanofabrication have developed a way of making flexible conductors cost-effective enough for commercial application."
but ours are made of ultra fine copper nanowires, using a fabrication process called freeze drying,
"Despite its conductivity, copper's tendency to oxidation and the poor mechanical stability of copper nanowire aerogel monoliths mean its potential has been unexplored largely.
"The conductivity can be tuned simply by adjusting the loading of copper nanowires, "he said.""A low loading of nano wires would be appropriate for a pressure sensor
the researchers noted that devices using their copper-based aerogels were not quite as sensitive as those using gold nanowires,
#Color hologram uses plasmonic nanoparticles to store large amounts of information In the 4th century, the Romans built a special glass cup,
Similar to the Lycurgus cup, the new holograms can change colors due to light scattering off silver nanoparticles of specific sizes and shapes.
The new holograms consist of precisely engineered silver nanoparticles patterned over a substrate. A key difference in the new holograms is the smaller size of the diffraction fringes,
the fringes here are replaced with nanoparticles smaller than half the wavelength of light. The researchers showed that the narrower band diffraction,
is produced by plasmonic-enhanced optical scattering of the nanostructures. The subwavelength distance offers certain advantages.
For instance, two different types of plasmonic nanoparticles can be multiplexed, or combined but not coupled, at subwavelength distances.
By using nanoparticles of silver with different shapes and sizes, the researchers could control the colors.
In addition to providing multiple colors, multiplexing two nanoparticles has the advantage of increasing the bandwidth information limits.
The researchers showed that each nanoparticle carries independent information such as polarization and wavelength, which can be controlled simultaneously.
With twice the number of nanoparticles, the total amount of binary information stored can exceed the traditional limits of diffraction."
"It has been shown that nanoparticles with resonant properties can be uncoupled over subwavelength distances so their electromagnetic fields have minimal interaction,
"The device presented demonstrates that these nanoparticles can store and transfer independent information beyond the diffraction limits,
We believe that it will also prompt new experiments focusing on the dynamical properties of the atoms at nanostructures,
#Graphene rubber bands could stretch limits of current healthcare New research published today in the journal ACS Nano identifies a new type of sensor that can monitor body movements
Now researchers from the University of Surrey and Trinity college Dublin have treated for the first time common elastic bands with graphene to create a flexible sensor that is sensitive enough for medical use
By fusing this material with graphene -which imparts an electromechanical response on movement the team discovered that the material can be used as a sensor to measure a patient's breathing heart rate
but our graphene-infused rubber bands could really help to revolutionise remote healthcare said Dr Alan Dalton from the University of Surrey.
#Bacterial nanowires: Not what we thought they were For the past 10 years scientists have been fascinated by a type of electric bacteria that shoots out long tendrils like electric wires using them to power themselves
Today a team led by scientists at USC has turned the study of these bacterial nanowires on its head discovering that the key features in question are not pili as previously believed
Scientists had suspected long that bacterial nanowires were pili Latin for hair which are hairlike features common on other bacteria allowing them to adhere to surfaces
Given the similarity of shape it was easy to believe that nanowires were pili. But Moh El-Naggar assistant professor at the USC Dornsife College of Letters Arts and Sciences says he was always careful to avoid saying that he knew for sure that's what they were.
with bacterial nanowires. This latest study will be published online by the Proceedings of the National Academy of Sciences on August 18.
During the formation of nanowires scientists noted an increase in the expression of electron transport genes but no corresponding increase in the expression of pilin genes.
what nanowires weren't the team next needed to figure out what they actually were. El-Naggar credits Sahand Pirbadian USC graduate student with devising an ingenious yet simple strategy to make the discovery.
By depriving the bacteria of oxygen the researchers were able to force the bacteria to stretch out their nanowires on command allowing the process to be observed in real time.
and specific proteins researchers were able to take video of the nanowires reaching out confirming that they were based on membrane and not pili at all.
Generating videos of the nanowires stretching out required new methods to simultaneously label multiple features keep a camera focused on the wriggling bacteria and combine the optical techniques with atomic force microscopy to gain higher resolution.
and figure out the right conditions for the bacteria to produce nanowires Pirbadian said. We had to go back
Once we were able to induce nanowire growth we started analyzing their composition and structure
Shewanella oneidensis MR-1 nanowires are outer membrane and periplasmic extensions of the extracellular electron transport components PNAS www. pnas. org/cgi/doi/10.1073
#Eco-friendly'prefab nanoparticles'could revolutionize nano manufacturing A team of materials chemists polymer scientists device physicists
and others at the University of Massachusetts Amherst today report a breakthrough technique for controlling molecular assembly of nanoparticles over multiple length scales that should allow faster cheaper more ecologically friendly manufacture of organic photovoltaics and other electronic devices.
It was Bag who put similar sized and charged nanoparticles together to form a building block then used an artist's airbrush to spray layers of electrical circuits atop each other to create a solar-powered device.
He says Here we preformed structures at nanoscale so they will form a known structure assembled at the meso scale from
#Magnetic nanoparticles break the capacity barrier for antibody purification Monoclonal antibodies represent the largest and fastest-growing segment of international biopharma.
Now A*STAR researchers have developed a high-capacity method to purify monoclonal antibodies that uses magnetic nanoparticles and also introduces new operating conditions.
which causes the antibodies to be deposited on the surface of starch-coated magnetic nanoparticles (see image).
The high capacity of our nanoparticle method makes it much faster than column chromatography explains Gagnon.
In addition to solving the longstanding problem of productivity for monoclonal antibodies the nanoparticle approach can be applied to many other therapeutic proteins and also to viral vaccines.
Gagnon P. Toh P. & Lee J. High productivity purification of Immunoglobulin g monoclonal antibodies on starch-coated magnetic nanoparticles by steric exclusion of polyethylene glycol.
#Pentagonal nanorods show catalytic promise Pentagonal nanorods have a unique morphology that confers interesting compositional
Now, researchers in Singapore have developed a simple chemical process to grow uniform pentagonal nanorods composed of gold and copper.
rendering them useful in the fields of materials chemistry and nanotechnology.""We successfully synthesized goldopper pentagonal nanorods with controlled size
and composition by a seed-mediated growth route,"explains lead researcher Jackie Ying from the A*STAR Institute of Bioengineering and Nanotechnology.
The'seeds'are multiple crystals of elongated gold decahedrons, joined together by shared facesn arrangement known as multiply-twinning.
To create the nanorods, the team placed the gold seeds in a solution containing a copper precursor and applied heat a process that produced nearly uniform pentagonal nanorods.
Ying's team showed that they could control the length of these nanorods by changing the amount of gold seeds added to the copper precursor.
Adding a 1: 1 ratio of gold to copper produced nanorods that grew approximately 15 nanometers in length while a 1: 2 ratio produced nanorods approximately 19 nanometers long,
and a 1: 3 ratio produced nanorods approximately 24 nanometers long. The diameter of the nanorods remained the same,
however, regardless of the ratio of metals used. The ability to control the size and composition of the nanorods means it is easier to control the properties of the bimetallic goldopper nanoparticles compared to nanoparticles made of just one metal,
Yang explains. Next, the team evaluated the catalytic activity of these goldopper nanorods in a carbonitrogen-bond-forming reactionhe direct alkylation of an amine using an alcohol."
"This hydrogen-borrowing strategy is an attractive synthetic method for the C bond formation as it is an environmentally friendly process
which produces only water as a byproduct, "says Ying. The nanorods were examined as catalysts for this reaction using the model substrates p-toluene sulphonamide and benzyl alcohol."
"Our heterogeneous catalyst showed higher catalytic activity toward the C coupling reaction and better recyclability compared to commercially available catalysts,
Her team now plans to use the nanorods as seeds themselves to synthesize nanoparticles comprised of a goldopper core surrounded by a shell of another material, such as platinum, for energy applications
which traps light at the nanoscale to enable real-time monitoring of individual molecules bending and flexing may aid in our understanding of how changes within a cell can lead to diseases such as cancer.
This critical front line of cellular defence is made up of a layer of fatty lipids just a few nanometres thick.
In order to view the behaviour of the cell membrane at the level of individual molecules the Cambridge team working with researchers from the University of Leeds squeezed them into a tiny gap between the mirrored gold facets of a nanoparticle sitting just above a flat gold surface.
Through highly precise control of the geometry of the nanostructures and using Raman spectroscopy an ultra-sensitive molecular identification technique the light can be trapped between the mirrors allowing the researchers to'fingerprint'individual molecules.
#Mobile phones come alive with the sound of music thanks to nanogenerators Charging mobile phones with sound, like chants from at football ground, could become a reality, according to a new collaboration between scientists from Queen Mary University of London and Nokia.
Nokia worked with the QMUL team to create an energy harvesting prototype (a nanogenerator) that could be used to charge a mobile phone using everyday background noise such as traffic,
or stretched creates a voltage by converting energy from motion into electrical energy, in the form of nanorods.
The nanorods can be coated onto various surfaces in different locations making the energy harvesting quite versatile.
the nanorods then generate a high voltage. The nanorods respond to vibration and movement created by everyday sound,
such as our voices. Electrical contacts on both sides of the rods are used then to harvest the voltage to charge a Phone in order to make it possible to produce these nanogenerators at scale
the scientists found innovative ways to cut costs in the production process. Firstly, they developed a process
whereby they could spray on the nanorod chemicals almost like nanorod graffiti to cover a plastic sheet in a layer of zinc oxide.
the nanorods grew all over the surface of the sheet. Secondly, gold is used traditionally as an electrical contact
Researchers from the Institut Català de Nanociència i Nanotecnologia's (ICN2 Catalan Institute of Nanoscience and Nanotechnology) Nanobioelectronics and Biosensors Group led by the ICREA Research Prof Arben Merkoçi work
#New graphene framework bridges gap between traditional capacitors batteries Researchers at the California Nanosystems Institute (CNSI) at UCLA have set the stage for a watershed in mobile energy storage by using a special graphene material
The material, called a holey graphene framework, has perforated a three-dimensional structure characterized by tiny holes;
In their study, published online August 8 in the journal Nature Communications, the CNSI researchers led by Duan used a highly interconnected 3d holey graphene framework as the electrode material to create an EC with unprecedented performance.
"By focusing on the nanoelectronic connections between cells, we can do things no one has done before,
By using nanoelectronics, it could become possible for scientists to peer for the first time inside cells, see what's going wrong in real time
His team has made ultrathin nanowires that can monitor and influence what goes on inside cells.
Graphene research on the cusp of new energy capabilities (Phys. org) There remains a lot to learn on the frontiers of solar power research particularly
Under the guidance of Canada Research Chair in Materials science with Synchrotron radiation Dr. Alexander Moewes University of Saskatchewan researcher Adrian Hunt spent his Phd investigating graphene oxide a cutting-edge material that he hopes will shape the future
To understand graphene oxide it is best to start with pure graphene which is a single-layer sheet of carbon atoms in a honeycomb lattice that was made first in 2004 by Andre Geim
All of this makes graphene a great candidate for solar cells. In particular its transparency and conductivity mean that it solves two problems of solar cells:
whereas graphene could be very cheap. Carbon is said abundant Hunt. Although graphene is a great conductor it is not very good at collecting the electrical current produced inside the solar cell
which is why researchers like Hunt are investigating ways to modify graphene to make it more useful.
Graphene oxide the focus of Hunt's Phd work has forced oxygen into the carbon lattice which makes it much less conductive but more transparent and a better charge collector.
Whether or not it will solve the solar panel problem is yet to be seen and researchers in the field are building up their understanding of how the new material works.
and SGM beamlines at the Canadian Light source as well as a Beamline 8. 0. 1 at the Advanced Light source Hunt set out to learn more about how oxide groups attached to the graphene lattice changed it
and how in particular they interacted with charge-carrying graphene atoms. Graphene oxide is fairly chaotic. You don't get a nice simple structure that you can model really easily but
I wanted to model graphene oxide and understand the interplay of these parts. Previous models had seemed simplistic to Hunt
and he wanted a model that would reflect graphene oxide's true complexity. Each different part of the graphene oxide has a unique electronic signature.
Using the synchrotron Hunt could measure where electrons were on the graphene and how the different oxide groups modified that.
He showed that previous models were incorrect which he hopes will help improve understanding of the effects of small shifts in oxidization.
Moreover he studied how graphene oxide decays. Some of the oxide groups are not stable and can group together to tear the lattice;
others can react to make water. If graphene oxide device has water in it and it is heated up the water can actually burn the graphene oxide and produce carbon dioxide.
It's a pitfall that could be important to understand in the development of long-lasting solar cells where sun could provide risky heat into the equation.
More research like this will be the key to harnessing graphene for solar power as Hunt explains.
There's this complicated chain of interreactions that can happen over time and each one of those steps needs to be addressed
Super-stretchable yarn is made of graphene More information: Hunt Adrian Ernst Z. Kurmaev and Alex Moewes.
A Re evaluation of How Functional Groups Modify the Electronic Structure of Graphene oxide. Advanced Materials (2014.
Presenting their findings today 5 august 2014 in the journal Nanotechnology the researchers have demonstrated the material's superior performance compared to commercially available carbon graphene and carbon nanotubes.
and also had a higher amount of storage compared to graphene and carbon nanotubes as reported in previous studies.
Explore further: Nano-supercapacitors for electric cars More information: Preparation of energy storage material derived from a used cigarette filter for a supercapacitor electrode Nanotechnology iopscience. iop. org/0957-4484/25/34/345601 5
#Nanoscale biodegradable drug-delivery method could provide a year or more of steady doses About one in four older adults suffers from chronic pain.
Many of those people take medication usually as pills. But this is not an ideal way of treating pain:
The method uses biodegradable nanoscale thin films laden with drug molecules that are absorbed into the body in an incremental process.
The film can be applied onto degradable nanoparticles for injection into local sites or used to coat permanent devices such as orthopedic implants.
Research on two-dimensional materials started with graphene, a material made of a single layer of carbon atoms.
analyse and improve ultra-thin layers by working with graphene. This know-how has now been applied to other ultra-thin materials."
#Surprise discovery could see graphene used to improve health (Phys. org) chance discovery about the'wonder material'graphene already exciting scientists because of its potential uses in electronics,
Researchers from Monash University have discovered that graphene oxide sheets can change structure to become liquid crystal droplets spontaneously and without any specialist equipment.
With graphene droplets now easy to produce, researchers say this opens up possibilities for its use in drug delivery and disease detection.
build on existing knowledge about graphene. One of the thinnest and strongest materials known to man,
graphene is a 2d sheet of carbon just one atom Thick with a'honeycomb'structure the'wonder material'is 100 times stronger than steel, highly conductive and flexible.
because graphene droplets change their structure in response to the presence of an external magnetic field,
"In contrast, graphene doesn't contain any magnetic properties. This combined with the fact that we have proved it can be changed into liquid crystal simply
"Usually atomisers and mechanical equipment are needed to change graphene into a spherical form. In this case all the team did was to put the graphene sheets in a solution to process it for industrial use.
Under certain PH conditions they found that graphene behaves like a polymer-changing shape by itself.
First author of the paper, Ms Rachel Tkacz from the Faculty of engineering, said the surprise discovery happened during routine tests."
"To be able to spontaneously change the structure of graphene from single sheets to a spherical assembly is hugely significant.
"Now we know that graphene-based assemblies can spontaneously change shape under certain conditions, we can apply this knowledge to see
This provides us with crucial information about the organisation of graphene sheets, enabling us to recognise these unique structures,
and Monash University and was the first linkage grant for graphene research in Australia s
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