and an assistant professor of materials science and engineering at NC State. This could make the manufacture of semiconductor devices an order of magnitude less expensive.
and metal when an intermediate layer of vanadium is present.##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.
Surface energy induced formation of single crystalline bismuth nanowires over vanadium thin film at room temperature. Nano Letters 14 5630#5635 (2014) DOI:
#Contact lens merges plastics and active electronics via 3-D printing (Phys. org) As part of a project demonstrating new 3-D printing techniques Princeton researchers have embedded tiny light-emitting diodes into a standard contact lens
The researchers used tiny crystals called quantum dots to create the LEDS that generated the colored light.
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
For this they developed a simple procedure to produce polymer vesicles small artificial bubbles with host cell receptors on the surface.
The preparation of such polymer vesicles with water-soluble host receptors was done by using a mixture of two different block copolymers.
The NC State researchers took a different approach placing nanoscale polystyrene spheres on the surface of the photosensitive film.
For this work we focused on creating nanostructures using photosensitive polymers which are used commonly in lithography Zhang says.
We're exploring the use of nanosphere materials other than polystyrene as well as nanoparticle shapes other than spheres Chang says.
#Atomic'mismatch'creates nano'dumbbells'Like snowflakes nanoparticles come in a wide variety of shapes and sizes.
and polymers. A paper describing this discovery by a research team led by John V. Badding a professor of chemistry at Penn State was published in the Sept. 21 issue of the journal Nature Materials.
so that when we release the pressure very slowly an orderly polymerization reaction happens that forms the diamond-core nanothread.
This is very straightforward rapid'cooking'of a metal-organic precursor in boiling water. The precursor compound is a solid tin alkoxide a material analogous to cost-efficient and broadly available titanium alkoxides.
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.
She precipitates the precious metal from an aqueous solution onto a pretreated film with many tiny channels.
The metal on the walls of the channels adopts the shape of nanotubes; the film is dissolved then.
"She preferred not to use cyanide, formaldehyde, arsenic and heavy metal salts. She was inspired by a journal article by researchers who achieved silver precipitation using coffee.
Although tests with bio-based plastics are already on the agenda, the films still consist of polycarbonate also made or of polyethylene terephthalate (PET).
In order to create the miniature plastic channels that define the shape, a round film is bombarded vertically with an ion beam.
Each ion leaves a straight track in the film which then becomes a small hole,
"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."
The nanoparticles naturally grow a hard shell of silicon oxide on their surface much like stainless steel forms a protective layer of chromium oxide on its surface.
and zinc metals a combination discovered for the first time. These are heated to a high temperature in the presence of a flow of carbon dioxide to produce a controlled metallothermic reaction.
or metals while attempting to sense light. Additionally the new material is capable of higher spatial resolution
"We believe that the results of this work are an important contribution to the use of inelastic electron tunnelling spectroscopy that will allow the technique to be used as an additional source of information in materials science
The materials commonly used for restoration such as coatings of synthetic polymers or inorganic materials have a different composition than that of the original artefacts
or exhibit a complex composition they can be classified as composite materials which means that you need materials science
and colloid and surface science to understand and eventually rescue these materials from possible degradation processes.
and vinyl polymers that seriously damage the painting and in many cases have led to the loss of painted surfaces.
and materials for modern and contemporary works of art such as acrylic paintings plastic sculptures and composite works that include metal textiles polymers etc.
In order to address this challenge we have created a unique partnership that groups research institutions and materials science experts together with high-profile museums conservation centres and experienced professionals in the field of modern art preservation.
Despite the pessimistic prognosis the researchers found that protons pass through the ultra-thin crystals surprisingly easily especially at elevated temperatures
and its sister material boron nitride attractive for possible uses as proton-conducting membranes which are at the heart of modern fuel cell technology.
or monolayer boron nitride can allow the existing membranes to become thinner and more efficient with less fuel crossover and poisoning.
#Researchers develop efficient method to produce nanoporous metals Nanoporous metals foam-like materials that have some degree of air vacuum in their structure have a wide range of applications because of their superior qualities.
Nanoporous metals offer an increased number of available sites for the adsorption of analytes a highly desirable feature for sensors.
Lawrence Livermore National Laboratory (LLNL) and The swiss Federal Institute of technology (ETH) researchers have developed a cost-effective and more efficient way to manufacture nanoporous metals over many scales from nanoscale to macroscale
A coating of metal is added and sputtered across the wafer. Gold silver and aluminum were used for this research project.
However the manufacturing process is limited not to these metals. Next a mixture of two polymers are added to the metal substrate to create patterns a process known as diblock copolymer lithography (BCP.
The pattern is transformed in a single polymer mask with nanometer-size features. Last a technique known as anisotropic ion beam milling (IBM) is used to etch through the mask to make an array of holes creating the nanoporous metal.
During the fabrication process the roughness of the metal is examined continuously to ensure that the finished product has good porosity
which is key to creating the unique properties that make nanoporous materials work. The rougher the metal is the less evenly porous it becomes.
During fabrication our team achieved 92 percent pore coverage with 99 percent uniformity over a 4-in silicon wafer which means the metal was smooth
and evenly porous said Tiziana Bond an LLNL engineer who is a member of the joint research team.
and metal surface roughness-by which the fabrication of nanoporous metals should be stopped when uneven porosity is known the outcome saving processing time and costs.
The real breakthrough is created that we a new technique to manufacture nanoporous metals that is cheap
and can be done over many scales avoiding the lift off technique to remove metals with real-time quality control Bond said.
These metals open the application space to areas such as energy harvesting sensing and electrochemical studies. The lift off technique is a method of patterning target materials on the surface of a substrate by using a sacrificial material.
Other applications of nanoporous metals include supporting the development of new metamaterials (engineered materials) for radiation-enhanced filtering
The high temperature processes essential for high performance electronic devices have restricted severely the development of flexible electronics because of the fundamental thermal instabilities of polymer materials.
A research team headed by Professor Keon Jae Lee of the Department of Materials science and engineering at KAIST provides an easier methodology to realize high performance flexible electronics by using the Inorganic-based Laser Lift off (ILLO.
because the pores are too small for optical microscopy and too flexible and mobile for X-ray crystallography."
First they made a sandwich composed of two metal electrodes separated by a two-nanometer thick insulating layer (a single nanometer is 10000 times smaller than a human hair) made by using a semiconductor technology called atomic layer deposition.
The results of the UC work will be presented at the Materials Research Society Conference in Boston Nov 30-Dec 5 by Andrew Dunn doctoral student in materials science engineering in UC's College of Engineering and Applied science.
Working with Dunn in this study are Donglu Shi professor of materials science engineering in UC's College of Engineering and Applied science;
Moving forward the team from NTU's School of Materials science and engineering will be looking to load multiple layers of drugs into their biomarker.
These polymer-based nanocomposites are reinforced with graphite nanoplatelets for use in industry. Nanocomposites are formed by two
or more constituents in this case the polymer and a nano-sized reinforcing material: the graphite nanoplatelets s
At issue are molybdenum sulfide (Mos2) thin films that are only one atom thick first developed by Dr. Linyou Cao an assistant professor of materials science and engineering at NC State.
nanoparticles comprised of a nontoxic biodegradable polymer matrix and insect derived double-stranded ribonucleic acid or dsrna.
This has a tremendous impact for many scientific areas including materials science chemistry and energy materials said co-author Volker Rose.
Even in its present form the techniques demonstrated here can revolutionize nanoscale imaging in realms far beyond materials science including electronics and biology.
Today it signals a promising discovery in materials science research that could help next-generation technology-like wearable energy storage devices-get off the ground.
and can be contorted into a variety of shapes is a rarity in the field of materials science.
Tensile strength-the strength of the material when it is stretched -and compressive strength-its ability to support weight-are valuable characteristics for these materials because at just a few atoms thick their utility figures almost entirely on their physical versatility.
Take the electrode of the small lithium-ion battery that powers your watch for example ideally the conductive material in that electrode would be very small
or tensile strength-we open a new world of possibilities. This flexible new material which the group has identified as a conductive polymer nanocomposite is the latest expression of the ongoing research in Drexel's Department of Materials science and engineering on a family of composite two-dimensional materials called MXENES.
This development was facilitated by collaboration between research groups of Yury Gogotsi Phd Distinguished University and Trustee Chair professor in the College of Engineering at Drexel and Jieshan Qiu vice dean for research
Zheng Ling a doctoral student from Dalian spent a year at Drexel spearheading the research that led to the first MXENE-polymer composites.
To produce the flexible conductive polymer nanocomposite the researchers intercalated the titanium carbide MXENE with polyvinyl alcohol (PVA)- a polymer widely used as the paper adhesive known as school
They also intercalated with a polymer called PDDA (polydiallyldimethylammonium chloride) commonly used as a coagulant in water purification systems.
The uniqueness of MXENES comes from the fact that their surface is full of functional groups such as hydroxyl leading to a tight bonding between the MXENE flakes and polymer molecules while preserving the metallic conductivity of nanometer-thin
When mixing MXENE with PVA containing some electrolyte salt the polymer plays the role of electrolyte
ions also stay trapped near the MXENE flakes by the polymer. With these conductive electrodes and no liquid electrolyte we can eventually eliminate metal current collectors
and polymer will affect the properties of the resulting nanocomposite and also exploring other MXENES and stronger and tougher polymers for structural applications.
Explore further: Crumpled graphene could provide an unconventional energy storag g
#Microtubes create cozy space for neurons to grow and grow fast Tiny, thin microtubes could provide a scaffold for neuron cultures to grow
Very thin membranes of silicon nitride roll themselves up into tubes of precise dimensions. The tubes are about as wide as the cells
The thin silicon nitride tubes are transparent, so researchers can watch the live neuron cells as they grow using a conventional microscope."
The nanocarriers are made from a polymer called polyethylene glycol (PEG) to which researchers attach the cancer-killing drug camptothecin (CPT) like bunches of grapes on a vine.
I did research on conducting plastics for electronic devices. When I moved into the cancer treatments with nanotechnology that's when my mum became really excited about my work.
First author Chanyuan Liu a graduate student in materials science & engineering says that it can be charged fully in 12 minutes
Gary Rubloff director of the Maryland Nanocenter and a professor in the Department of Materials science and engineering and in the Institute for Systems Research;
Sang Bok Lee a professor in the Department of chemistry and Biochemisty and the Department of Materials science and engineering;
Using electron beam lithography she then stamps the pattern onto a polymer matrix and the nanowires are grown by applying electric current through electrodeposition.
The entire structure is surrounded by a polymer matrix. Nath and her research team can produce wires of any shape or size.
The polymer which is nonconductive can be removed to allow the wires to stand freely and yet not lose shape or consistency.
The actual micro-scallop was made of a relatively hard plastic. The challenge was to make the shells extremely thin
As in the case of their plastic micro-scallop the researchers also envision medical applications for their nanosubmarine.
Lee and Alex Zettl, a physicist who holds joint appointments with Berkeley Lab's Materials sciences Division
In a study led by Xiang Zhang director of Berkeley Lab's Materials sciences Division he and his research group at the University of California (UC) Berkeley achieved symmetry-breaking in a bulk metamaterial solution for the first time.
This crystal structure creates a more robust edge and the more edge the better for catalytic reactions
but traditionally employed to thicken natural oxide layers on metals. The film was exposed then to sulfur vapor at 300 degrees Celsius (572 degrees Fahrenheit) for one hour.
and produce the first commercial scanners early next year, says cofounder Ling Zang, a professor of materials science and engineering and senior author of a study of the technology published online Nov 4 in the journal
Zang and his team found a way to break up bundles of the carbon nanotubes with a polymer
"By modifying the surface of the nanotubes with a polymer, the material can be tuned to detect any of more than a dozen explosives,
#Researchers improve thermal conductivity of common plastic by adding graphene coating (Phys. org) A team of engineering
and physics researchers with members from the U s. the U k. and the Republic of Muldova has found that covering a common type of plastic with a graphene coating can increase its conductivity by up to 600 times.
Plastics are not very good conductors of heat they are generally in the 0. 15-0. 24 W/mk range
In this new effort the researchers sought to improve heat conduction in a plastic by applying graphene to its surface.
The type of plastic used PET is very common it's used to make soda bottles and a myriad of other products in a nearly limitless variety of shapes.
which are based on multiscale simulations that will shed light on which sorts of real-world applications the coated plastics might best be used in.
Thermal conductivity of Graphene Laminate Nano Lett. 2014 14 (9) pp 5155-5161. DOI: 10.1021/nl501996v.
http://arxiv. org/ftp/arxiv/papers/1407/1407.1359. pdfabstractwe have investigated thermal conductivity of graphene laminate films deposited on polyethylene terephthalate substrates.
and a set of suspended samples with the graphene laminate thickness from 9 to 44 m. The thermal conductivity of graphene laminate was found to be in the range from 40 to 90 W/mk at room temperature.
The thermal conductivity scales up linearly with the average graphene flake size in both uncompressed and compressed laminates.
The compressed laminates have higher thermal conductivity for the same average flake size owing to better flake alignment.
Coating plastic materials with thin graphene laminate films that have up to 600 higher thermal conductivity than plastics may have important practical implications s
and revealed the widespread transition from one crystal structure to another. The team also measured the amount of oxygen
and carbon dioxide released by the NCA sample a key indicator of potential flammability. The oxygen release peaked between 300 and 400 degrees Celsius during our trials
This interfacial layer is critical to our understanding of a diverse set of phenomena from biology to materials science.
Miquel Salmeron a senior scientist in Berkeley Lab's Materials sciences Division (MSD) and professor in UC Berkeley's Materials science and engineering Department explains this in the context of a battery.
depositing thin films of a uniquely designed polymer on a template so that it self-assembles into neat, precise, even rows of alternating composition just 10 or so nanometers wide.
and IBM Almaden Research center focuses on block copolymers a special class of polymers that under the proper conditions, will segregate on a microscopic scale into regularly spaced"domains"of different chemical composition.
and measure the shape and dimensions of the polymer rows in three dimensions. The experimental techniques can prove essential in verifying
Hence the polymers.""The issue in semiconductor lithography is not really making small featuresou can do thatut you can't pack them close together,
"Block copolymers take advantage of the fact that if I make small features relatively far apart, I can put the block copolymer on those guiding patterns
and sort of fill in the small details.""The strategy is called"density multiplication"and the technique,"directed self-assembly."
"Block copolymers (BCPS) are a class of materials made by connecting two or more different polymers that,
the BCPS in question will form a thin film in a pattern of narrow, alternating stripes of the two polymer compositions.
Alternatively, they can be designed so one polymer forms a pattern of posts embedded in the other.
Remove one polymer, and in theory, you have a near-perfect pattern for lines spaced 10 to 20 nanometers apart to become, perhaps, part of a transistor array.
although the basic technique was developed using short wavelength"hard"X rays that have difficulty distinguishing two closely related polymers,
***Unlike the scattering technique, the TEM tomography can actually image defects in the polymer structureut only for a small area.
because its two-dimensional structure and unique chemical properties made it a promising candidate for new applications such as energy storage material composites as well as computing
Graphene is remarkably strong for its low weight-about 100 times stronger than steel -and it conducts heat and electricity with great efficiency.
The global market for graphene is reported to have reached US$9 million this year with most sales concentrated in the semiconductor electronics battery energy and composites.
and patented a nanofluid improving thermal conductivity at temperatures up to 400°C without assuming an increase in costs
and it offers enhanced thermal conductivity properties (an increase of up to 30%)of existing heat transfer fluids.
One characteristic that is common to all of them, according to Juliá, is"their low thermal conductivity, which is what limits the efficiency of the heat exchange systems that use them.
and increases the thermal conductivity by adding an exact proportion of nanoparticles consisting on carbon and other additives to the base fluid (diphenyl/diphenyl oxide),
it becomes possible to obtain increases of up to 30%in the thermal conductivity of the base fluid.
however because conventional metal electrode technologies are too thick(>500 nm) to be transparent to light making them incompatible with many optical approaches.
The new device uses graphene a recently discovered form of carbon on a flexible plastic backing that conforms to the shape of tissue.
Moreover graphene is nontoxic to biological systems an improvement over previous research into transparent electrical contacts that are much thicker rigid difficult to manufacture and reliant on potentially toxic metal alloys.
Hersam a professor of materials science engineering chemistry and medicine at Northwestern University has developed a method to separate nanomaterials by size
Kuzum emphasizes that the transparent graphene microelectrode technology was achieved through an interdisciplinary effort of CNT and the departments of Neuroscience Pediatrics and Materials science at Penn and the division of Neurology at CHOP.
Ertugrul Cubukcu's lab at Materials science and engineering Department helped with the graphene processing technology used in fabricating flexible transparent neural electrodes as well as performing optical and materials characterization in collaboration with Euijae Shim and Jason Reed.
To overcome this challenge the researchers from the Institute for Integrated Cell-Material Sciences (icems) at Kyoto University borrowed a principle from polymer chemistry
By putting graphene oxide (an oxidized form of graphene) into contact with an oppositely charged polymer the two components could form a stable composite layer a process also known as interfacial complexation.
Interestingly the polymer could continuously diffuse through the interface and induce additional reactions which allowed the graphene-based composite to develop into thick multilayered structures.
Hence we named this process'diffusion driven layer-by-layer assembly'explained Jianli Zou a co-investigator in the project.
"said Ragan, associate professor of chemical engineering & materials science and principal investigator on the project. This grant highlights the strength of our faculty in both nanosciences
In recent years carbon nanotubes have emerged as a promising material of electron field emitters owing to their nanoscale needle shape and extraordinary properties of chemical stability thermal conductivity and mechanical strength.
and genetic diseases by combining the chemical specificity of the DNA with the signal readout of the metal.
The system is built around a polyethylene-glycol-based polymer that carries a small peptide component that allows it to bind preferentially to specific cell types The polymer itself serves as a photosensitizer that can be stimulated by light to release reactive oxygen species (ROS.
The natural fluorescence of the polymer assists with diagnosis and monitoring of therapy as it shows where nanoparticles have accumulated.
The ROS additionally break the link between the polymer and the doxorubicin. Thus cancer cells can be subjected to a two-pronged attack from the ROS therapy
Surface tension wicks the fluid up the side of the emitters to the tip of the cone whose narrowness concentrates the electrostatic field.
their crystal structure is influenced not by the process. The UT scientists present their#findings in the journal Advanced Functional Materials.
Within the group Inorganic Materials science UT scientists have gained a lot of experience with these materials: earlier the group developed the Pulsed laser deposition technique (PLD)# for this building the materials one atomic layer at a time.
because other patterning techniques have the risk of damaging the crystal structure and orientation and thus influence the properties of the material.
and consists of PDMS#a rubber like polymer with silicon in it. Via this mask a pattern of zinc oxide can be placed on the perovskite for example.
Using PLD a sandwich of different materials can be made. The properties of each layer are secured.
They are also suitable for fundamental research in physics and materials science. Research has been done within the Inorganic Materials science group part of the MESA+Institute for Nanotechnology at the University of Twente.
The paper'Patterning of epitaxial perovskites from micro and nano molded stencil masks'by Maarten Nijland Antony George Sean Thomas Evert Houwman Jing Xia Dave Blank Guus Rijnders Gertjan Koster
Kim tried adding different polymers to his nanosheets to make them responsive. For this experiment he incorporated a relatively simple polymer that responds to ph. He found that the resulting nanosheet would always curl in basic high ph conditions
and always flatten in acidic low ph conditions. Kim also made his nanosheets responsive to near-infrared light a wavelength of light that is harmless to humans.
creating a responsive nanosheet is just a matter of adding the right polymer. A nanosheet is like pizza dough Kim said.
A nanosheet with a heat-sensitive polymer could burn surrounding tumors to destroy them functioning as a kind of super-specific chemotherapy.
There are tons of smart polymers and metals Kim said explaining the many properties he hopes to incorporate into nanotechnology.
This new structure is composite which means it allows us to mix all different kinds of components.
Smart Composite Nanosheets with Adaptive Optical Properties Jeong-Hwan Kim Murtaza Bohra Vidyadhar Singh Cathal Cassidy and Mukhles Sowwan Applied materials & Interfaces2014.
The best carbon nanotubes (CNTS) have demonstrated conductivities far beyond those of the best metals. Thus future windings made of CNTS may have a double conductivity compared with the present-day copper windings.
which has the second best conductivity of metals at room temperature. Despite the high conductivity of copper a large proportion of the electrical machine losses occur in the copper windings.
Carbon nanotubes are rapidly becoming more common because of their usefulness in nanoelectric devices composite materials and biomedicine.
a professor of materials science and engineering at Illinois."Our current understanding of nanoscale thermal transport isn't nuanced enough to quantitatively predict
"Our study focused on a variety of crystals that have controlled differences in thermal transport properties, such as Si, doped Si,
and Sige alloys,"Wilson said.""We coated these crystals with a thin metal film, heated the surface with a laser beam,
and then recorded the temperature evolution of the sample.""On length-scales shorter than the phonon mean-free-paths of the crystal,
heat is transported ballistically, not diffusively. Interfaces between materials further complicate the heat-transfer problem by adding additional thermal resistance."
when the radius of the laser beam used to heat the metal coated crystals was above ten microns,
predicts that a cubic crystal like silicon will carry heat equally well in all directions.
In particularly for crystals with defects, the boundary resistance is distributed and strongly dependent on the defect concentration."
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