Read Genesis Nanotech Online: Latest ‘Nano’-News and Updates: Articles Like …


 

cropped-microbots-water.jpgGenesis Nanotechnology ~ “Great Things from Small Things”

Read More At:

https://paper.li/GenesisNanoTech/1354215819#!headlines

Nano Antennas 072016 160718161257_1_540x360Rice University: Technology marries light-harvesting nanoantennas to high-reaction-rate catalysts: Could transform some of the world’s most energy-intensive manufacturing processes

 

 

auto thin trans 072016 berkeleylabsU.S. Department of Energy’s Lawrence Berkeley National Laboratory: Scientists grow atomically thin transistors and circuits

 

 

 

tHIS TRANSISTORS 072016 578d2684a1c34NC State U: Faster-More Precise Silica coating process for Quantum Dot nanorods: Makes Nano-scale Semi-Conductor materials less likely to degrade – keeps optical properties.

 

 

 

img_0664

Genesis Nanotechnology, Inc. ~ “Great Things from Small Things”

Facebook 042616.jpgFollow Us on Facebook

Twitter Icon 042616.jpgUp to the Minute Nanotech News on Our Twitter Feed

LinkedIn IconA 042316.jpg‘Link-Up” with Us on LinkedIn

 

   Website Icon 042616Connect with Our Website

YouTube small 050516Watch Our YouTube Video 

Electricity generated with water, salt and a three-atoms-thick membrane: NEW Osmotic Power


Electricity from Water Salt - 3 Atoms 072016 578660a2f2413A molybdenum 3-atoms-thick selective membrane. Credit: © Steven Duensing / National Center for Supercomputing Applications, University of Illinois, Urbana-Champaign

Proponents of clean energy will soon have a new source to add to their existing array of solar, wind, and hydropower: osmotic power. Or more specifically, energy generated by a natural phenomenon occurring when fresh water comes into contact with seawater through a membrane.

Researchers at EPFL’s Laboratory of Nanoscale Biology have developed an osmotic power generation system that delivers never-before-seen yields. Their innovation lies in a three atoms thick membrane used to separate the two fluids. The results of their research have been published in Nature.

The concept is fairly simple. A semipermeable membrane separates two fluids with different salt concentrations. Salt- travel through the membrane until the salt concentrations in the two fluids reach equilibrium. That phenomenon is precisely osmosis.

If the system is used with seawater and fresh water, salt ions in the seawater pass through the membrane into the fresh water until both fluids have the same salt concentration. And since an ion is simply an atom with an electrical charge, the movement of the can be harnessed to generate electricity.

A 3 atoms thick, selective membrane that does the job

EPFL’s system consists of two liquid-filled compartments separated by a thin membrane made of molybdenum disulfide. The membrane has a tiny hole, or nanopore, through which seawater ions pass into the until the two fluids’ salt concentrations are equal. As the ions pass through the nanopore, their electrons are transferred to an electrode – which is what is used to generate an electric current.

Thanks to its properties the membrane allows positively-charged ions to pass through, while pushing away most of the negatively-charged ones. That creates voltage between the two liquids as one builds up a positive charge and the other a negative charge. This voltage is what causes the current generated by the transfer of ions to flow.

“We had to first fabricate and then investigate the optimal size of the nanopore. If it’s too big, can pass through and the resulting voltage would be too low. If it’s too small, not enough ions can pass through and the current would be too weak,” said Jiandong Feng, lead author of the research.

What sets EPFL’s system apart is its membrane. In these types of systems, the current increases with a thinner membrane. And EPFL’s membrane is just a few atoms thick. The material it is made of – molybdenum disulfide – is ideal for generating an osmotic current. “This is the first time a two-dimensional material has been used for this type of application,” said Aleksandra Radenovic, head of the laboratory of Nanoscale Biology

Powering 50’000 energy-saving light bulbs with 1m2 membrane

The potential of the new system is huge. According to their calculations, a 1m² membrane with 30% of its surface covered by nanopores should be able to produce 1MW of electricity – or enough to power 50,000 standard energy-saving light bulbs. And since (MoS2) is easily found in nature or can be grown by chemical vapor deposition, the system could feasibly be ramped up for large-scale power generation. The major challenge in scaling-up this process is finding out how to make relatively uniform pores.

Until now, researchers have worked on a membrane with a single nanopore, in order to understand precisely what was going on. ” From an engineering perspective, single nanopore system is ideal to further our fundamental understanding of -based processes and provide useful information for industry-level commercialization”, said Jiandong Feng.

The researchers were able to run a nanotransistor from the current generated by a single nanopore and thus demonstrated a self-powered nanosystem. Low-power single-layer MoS2 transistors were fabricated in collaboration with Andreas Kis’ team at at EPFL, while molecular dynamics simulations were performed by collaborators at University of Illinois at Urbana-Champaign

Harnessing the potential of estuaries

EPFL’s research is part of a growing trend. For the past several years, scientists around the world have been developing systems that leverage osmotic power to create electricity. Pilot projects have sprung up in places such as Norway, the Netherlands, Japan, and the United States to generate energy at estuaries, where rivers flow into the sea. For now, the membranes used in most systems are organic and fragile, and deliver low yields. Some systems use the movement of water, rather than ions, to power turbines that in turn produce electricity.

Once the systems become more robust, osmotic power could play a major role in the generation of renewable energy. While solar panels require adequate sunlight and wind turbines adequate wind, osmotic energy can be produced just about any time of day or night – provided there’s an estuary nearby.

More information: Jiandong Feng et al, Single-layer MoS2 nanopores as nanopower generators, Nature (2016). DOI: 10.1038/nature18593

Provided by: Ecole Polytechnique Federale de Lausanne

Washington State U: Key improvement for fuel cells: Work improves understanding of process that improves one of the primary failure points


Fuel Cell II o72016 photo_stationary_fuel_cell

Washington State University researchers have determined a key step in improving solid oxide fuel cells (SOFCs), a promising clean energy technology that has struggled to gain wide acceptance in the marketplace.

The researchers determined a way to improve one of the primary failure points for the fuel cell, overcoming key issues that have hindered its acceptance. Their work is featured on the cover of the latest issue of Journal of Physical Chemistry C.

Fuel cells offer a clean and highly efficient way to convert the chemical energy in fuels directly into electrical energy. They are similar to batteries in that they have an anode, cathode and electrolyte and create electricity, but they use fuel to create a continuous flow of electricity.

Fuel cells can be about four times more efficient than a combustion engine because they are based on electrochemical reactions, but researchers continue to struggle with making them cheaply and efficiently enough to compete with traditional power generation sources.

An SOFC is made of solid materials, and the electricity is created by oxygen ions traveling through the fuel cell. Unlike other types of fuel cells, SOFCs don’t require the use of expensive metals, like platinum, and can work with a large variety of fuels, such as gasoline or diesel fuel.

When gasoline is used for fuel, however, a carbon-based material tends to build up in the fuel cell and stop the conversion reaction. Other chemicals, in particular sulfur, can also poison and stop the reactions.

In their study, the WSU researchers improved understanding of the process that stops the reactions. Problems most often occur at a place on the anode’s surface, called the triple-phase boundary, where the anode connects with the electrolyte and fuel.

The researchers determined that the presence of an electric field at this boundary can prevent failures and improve the system’s performance. To properly capture the complexity of this interface, they used the Center for Nanoscale Materials supercomputer at the Argonne National Laboratory to perform computations.

The researchers studied similar issues in solid oxide electrolysis cells (SOECs), which are like fuel cells that run in reverse to convert carbon dioxide and water to transportation fuel precursors.

The work provides guidance that industry can eventually use to reduce material buildup and poisoning and improve performance of SOFCs and SOECs, said Jean-Sabin McEwen, assistant professor in the Gene and Linda Voiland School of Chemical Engineering and Bioengineering, who led the project.

The research is in keeping with WSU’s Grand Challenges, a suite of research initiatives aimed at large societal issues. It is particularly relevant to the challenge of sustainable resources and its theme of energy.


Story Source:

The above post is reprinted from materials provided byWashington State University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Fanglin Che, Su Ha, Jean-Sabin McEwen. Elucidating the Role of the Electric Field at the Ni/YSZ Electrode: A DFT Study. The Journal of Physical Chemistry C, 2016; 120 (27): 14608 DOI: 10.1021/acs.jpcc.6b01292

NC State U: Faster-More Precise Silica coating process for Quantum Dot nanorods: Makes Nano-scale Semi-Conductor materials less likely to degrade – keeps optical properties.


Silica Coating for QD 072016 160711121519_1_540x360Morphological control of the silica shell on CdSe/CdS core/shell quantum dot nanorods is reported, giving single or double lobes of silica or a uniform silica shell.
Credit: Joe Tracy

Materials researchers at North Carolina State University have fine-tuned a technique that enables them to apply precisely controlled silica coatings to quantum dot nanorods in a day — up to 21 times faster than previous methods. In addition to saving time, the advance means the quantum dots are less likely to degrade, preserving their advantageous optical properties.

Quantum dots are nanoscale semiconductor materials whose small size cause them to have electron energy levels that differ from larger-scale versions of the same material. By controlling the size of the quantum dots, researchers can control the relevant energy levels — and those energy levels give quantum dots novel optical properties. These characteristics make quantum dots promising for applications such as opto-electronics and display technologies.

But quantum dots are surrounded by ligands, which are organic molecules that are sensitive to heat. If the ligands are damaged, the optical properties of the quantum dots suffer.

“We wanted to coat the rod-shaped quantum dots with silica to preserve their chemical and optical properties,” says Bryan Anderson, a former Ph.D. student at NC State who is lead author of a paper on the work. “However, coating quantum dot nanorods in a precise way poses challenges of its own.”

Previous work by other research teams has used water and ammonia in solution to facilitate coating quantum dot nanorods with silica. However, those techniques did not independently control the amounts of water and ammonia used in the process.

By independently controlling the amounts of water and ammonia used, the NC State researchers were able to match or exceed the precision of silica coatings achieved by previous methods. In addition, using their approach, the NC State team was able to complete the entire silica-coating process in a single day — rather than up to one to three weeks needed for other processes.

“The process time is important, because the longer the process takes, the more likely it is that the quantum dot nanorods being coated will degrade,” says Joe Tracy, an associate professor of materials science and engineering at NC State and senior author on the paper. “The time factor may also be important when we think about scaling this process up for manufacturing processes.”

That said, researchers still have a problem.

The process of applying the silica coating etches the cadmium sulfide surface of the quantum dot nanorods, which shortens the length of the nanorods by as much as four or five nanometers. That shortening is indicative of etching, which reduces the brightness of the light emitted by the quantum dot nanorods.

“We think ammonia may be the culprit,” Tracy says. “We have some ideas that we’re pursuing, focused on how to substitute another catalyst for ammonia in order to minimize the etching and better preserve the quantum dot nanorod’s optical properties.”

The paper, “Silica Overcoating of CdSe/CdS Core/Shell Quantum Dot Nanorods with Controlled Morphologies,” is published online in the journal Chemistry of Materials. The paper was co-authored by Wei-Chen Wu, a former Ph.D. student in Tracy’s lab. The work was done with support from the National Science Foundation under grant number DMR-1056653.

Tracy has previously published related research in Chemistry of Materials on coating gold nanorods with silica shells.


Story Source:

The above post is reprinted from materials provided by North Carolina State University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Bryan D. Anderson, Wei-Chen Wu, Joseph B. Tracy. Silica Overcoating of CdSe/CdS Core/Shell Quantum Dot Nanorods with Controlled Morphologies. Chemistry of Materials, 2016; DOI: 10.1021/acs.chemmater.6b01225

Rice University: Technology marries light-harvesting nanoantennas to high-reaction-rate catalysts: Could transform some of the world’s most energy-intensive manufacturing processes


Nano Antennas 072016 160718161257_1_540x360A composite image shows a scanning transmission electron microscope view of an antenna-reactor catalyst particle (top left) along with electron energy loss spectroscopy maps that depict the spatial distribution of individual plasmon modes around the palladium islands. These plasmon modes are responsible for capturing light energy and transferring it to the catalyst particles.
Credit: D. Swearer/Rice University

In a find that could transform some of the world’s most energy-intensive manufacturing processes, researchers at Rice University’s Laboratory for Nanophotonics have unveiled a new method for uniting light-capturing photonic nanomaterials and high-efficiency metal catalysts.

Each year, chemical producers spend billions of dollars on metal catalysts, materials that spur or speed up chemical reactions. Catalysts are used to produce trillions of dollars worth of chemical products. Unfortunately, most catalysts only work at high temperatures or high pressure or both. For example, the U.S. Energy Information Agency estimated that in 2010, just one segment of the U.S. chemical industry, plastic resin production, used almost 1 quadrillion British thermal units of energy, about the same amount of energy contained in 8 billion gallons of gasoline.

Nanotechnology researchers have long been interested in capturing some of the worldwide catalysis market with energy-efficient photonic materials, metallic materials that are tailor-made with atomic precision to harvest energy from sunlight. Unfortunately, the best nanomaterials for harvesting light — gold, silver and aluminum — aren’t very good catalysts, and the best catalysts — palladium, platinum and rhodium — are poor at capturing solar energy.

The new catalyst, which is described in a study this week in theProceedings of the National Academy of Sciences, is the latest innovation from LANP, a multidisciplinary, multi-investigator research group headed by photonics pioneer Naomi Halas. Halas, who also directs Rice’s Smalley-Curl Institute, said a number of studies in recent years have shown that light-activated “plasmonic” nanoparticles can be used to increase the amount of light absorbed by adjacent dark nanoparticles. Plasmons are waves of electrons that slosh like a fluid across the surface of tiny metallic nanoparticles. Depending upon the frequency of their sloshing, these plasmonic waves can interact with and harvest the energy from passing light.

In summer 2015, Halas and study co-author Peter Nordlander designed an experiment to test whether a plasmonic antenna could be attached to a catalytic reactor particle. Graduate student Dayne Swearer worked with them, Rice materials scientist Emilie Ringe and others at Rice and Princeton University to produce, test and analyze the performance of the “antenna-reactor” design.

Swearer began by synthesizing 100-nanometer-diameter aluminum crystals that, once exposed to air, develop a thin 2- to 4-nanometer-thick coating of aluminum oxide. The oxidized particles were then treated with a palladium salt to initiate a reaction that resulted in small islands of palladium metal forming on the surface of the oxidized particles. The unoxidized aluminum core serves as the plasmonic antenna and the palladium islands as the catalytic reactors.

Swearer said the chemical industry already uses aluminum oxide materials that are dotted with palladium islands to catalyze reactions, but the palladium in those materials must be heated to high temperatures to become an efficient catalyst.

“You need to add energy to improve the catalytic efficiency,” he said. “Our catalysts also need energy, but they draw it directly from light and require no additional heating.”

One example of a process where the new antenna-reactor catalysts could be used is for reacting acetylene with hydrogen to produce ethylene, Swearer said.

Ethylene is the chemical feedstock for making polyethylene, the world’s most common plastic, which is used in thousands of everyday products. Acetylene, a hydrocarbon that’s often found in the gas feedstocks that are used at polyethylene plants, damages the catalysts that producers use to convert ethylene to polyethylene. For this reason, acetylene is considered a “catalyst poison” and must be removed from the ethylene feedstock — often with another catalyst — before it can cause damage.

One way producers remove acetylene is to add hydrogen gas in the presence of a palladium catalyst to convert the poisonous acetylene into ethylene — the primary component needed to make polyethylene resin. But this catalytic process also produces another gas, ethane, in addition to ethylene. Chemical producers try to tailor the process to produce as much ethylene and as little ethane possible, but selectivity remains a challenge, Swearer said.

As a proof-of-concept for the new antenna-reactor catalysts, Swearer, Halas and colleagues conducted acetylene conversion tests at LANP and found that the light-driven antenna-reactor catalysts produced a 40-to-1 ratio of ethylene to ethane, a significant improvement in selectivity over thermal catalysis.

Swearer said the potential energy savings and improved efficiency of the new catalysts are likely to capture the attention of chemical producers, even though their plants are not currently designed to use solar-powered catalysts.

“The polyethylene industry produces more than $90 billion of products each year, and our catalysts turn one of the industry’s poisons into a valuable commodity,” he said.

Halas said she is most excited about the broad potential of the antenna-reactor catalytic technology.

“The antenna-reactor design is modular, which means we can mix and match the materials for both the antenna and the reactor to create a tailored catalyst for a specific reaction,” she said. “Because of this flexibility, there are many, many applications where we believe this technology could outperform existing catalysts.”


Story Source:

The above post is reprinted from materials provided by Rice University. The original item was written by Jade Boyd. Note: Materials may be edited for content and length.


Journal Reference:

  1. D. F. Swearer, H. Zhao, L. Zhou, C. Zhang, H. Robatjazi, J. M. P. Martirez, C. M. Krauter, S. Yazdi, M. J. McClain, E. Ringe, E. A. Carter, P. Nordlander, N. J. Halas.Heterometallic Antenna-Reactor Complexes for Photocatalysis. Proc. Natl. Acad. Sci., 2016 DOI:10.1073/pnas.1609769113

U.S. Department of Energy’s Lawrence Berkeley National Laboratory: Scientists grow atomically thin transistors and circuits


auto thin trans 072016 berkeleylabsThis schematic shows the chemical assembly of two-dimensional crystals. Graphene is first etched into channels and the TMDC molybdenum disulfide (MoS2) begins to nucleate around the edges and within the channel. On the edges, MoS2 slightly …more

In an advance that helps pave the way for next-generation electronics and computing technologies—and possibly paper-thin gadgets —scientists with the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) developed a way to chemically assemble transistors and circuits that are only a few atoms thick.

What’s more, their method yields functional structures at a scale large enough to begin thinking about real-world applications and commercial scalability.

They report their research online July 11 in the journal Nature Nanotechnology.

The scientists controlled the synthesis of a transistor in which narrow channels were etched onto conducting graphene, and a semiconducting material called a transition-metal dichalcogenide, or TMDC, was seeded in the blank channels. Both of these materials are single-layered crystals and atomically thin, so the two-part assembly yielded electronic structures that are essentially two-dimensional. In addition, the synthesis is able to cover an area a few centimeters long and a few millimeters wide.

“This is a big step toward a scalable and repeatable way to build atomically thin electronics or pack more computing power in a smaller area,” says Xiang Zhang, a senior scientist in Berkeley Lab’s Materials Sciences Division who led the study.

Zhang also holds the Ernest S. Kuh Endowed Chair at the University of California (UC) Berkeley and is a member of the Kavli Energy NanoSciences Institute at Berkeley. Other scientists who contributed to the research include Mervin Zhao, Yu Ye, Yang Xia, Hanyu Zhu, Siqi Wang, and Yuan Wang from UC Berkeley as well as Yimo Han and David Muller from Cornell University.

Their work is part of a new wave of research aimed at keeping pace with Moore’s Law, which holds that the number of transistors in an integrated circuit doubles approximately every two years. In order to keep this pace, scientists predict that integrated electronics will soon require transistors that measure less than ten nanometers in length.

Transistors are electronic switches, so they need to be able to turn on and off, which is a characteristic of semiconductors. However, at the nanometer scale, likely won’t be a good option. That’s because silicon is a bulk material, and as electronics made from silicon become smaller and smaller, their performance as switches dramatically decreases, which is a major roadblock for future electronics.

Researchers have looked to two-dimensional crystals that are only one molecule thick as alternative materials to keep up with Moore’s Law. These crystals aren’t subject to the constraints of silicon.

In this vein, the Berkeley Lab scientists developed a way to seed a single-layered semiconductor, in this case the TMDC molybdenum disulfide (MoS2), into channels lithographically etched within a sheet of conducting graphene. The two atomic sheets meet to form nanometer-scale junctions that enable graphene to efficiently inject current into the MoS2. These junctions make atomically thin transistors.

“This approach allows for the chemical assembly of electronic circuits, using two-dimensional materials, which show improved performance compared to using traditional metals to inject current into TMDCs,” says Mervin Zhao, a lead author and Ph.D. student in Zhang’s group at Berkeley Lab and UC Berkeley.

Optical and electron microscopy images, and spectroscopic mapping, confirmed various aspects related to the successful formation and functionality of the two-dimensional transistors.

In addition, the scientists demonstrated the applicability of the structure by assembling it into the logic circuitry of an inverter. This further underscores the technology’s ability to lay the foundation for a chemically assembled atomic computer, the scientists say.

“Both of these two-dimensional crystals have been synthesized in the wafer scale in a way that is compatible with current semiconductor manufacturing. By integrating our technique with other growth systems, it’s possible that future computing can be done completely with atomically thin crystals,” says Zhao.

Explore further: Excitonic dark states shed light on TMDC atomic layers

More information: Large-scale chemical assembly of atomically thin transistors and circuits, Nature Nanotechnology, DOI: 10.1038/nnano.2016.115

Read more at: http://phys.org/news/2016-07-scientists-atomically-thin-transistors-circuits.html#jCp

Read more at: http://phys.org/news/2016-07-scientists-atomically-thin-transistors-circuits.html#jCp

U of Texas – Austin: Scientists glimpse inner workings of atomically thin transistors


tHIS TRANSISTORS 072016 578d2684a1c34

With an eye to the next generation of tech gadgetry, a team of physicists at The University of Texas at Austin has had the first-ever glimpse into what happens inside an atomically thin semiconductor device. In doing so, they discovered that an essential function for computing may be possible within a space so small that it’s effectively one-dimensional.

In a paper published July 18 in the Proceedings of the National Academy of Sciences, the researchers describe seeing the detailed inner workings of a new type of transistor that is two-dimensional.

Transistors act as the building blocks for computer chips, sending the electrons on and off switches required for computer processing. Future tech innovations will require finding a way to fit more on computer chips, so experts have begun exploring new semiconducting materials including one called molybdenum disulfide (MoS2). Unlike today’s silicon-based devices, transistors made from the new material allow for on-off signaling on a single flat plane.

Keji Lai, an assistant professor of physics, and a team found that with this new material, the conductive signaling happens much differently than with silicon, in a way that could promote future energy savings in devices. Think of as light bulbs: The whole device is either turned on or off at once. With 2-D transistors, by contrast, Lai and the team found that electric currents move in a more phased way, beginning first at the edges before appearing in the interior. Lai says this suggests the same current could be sent with less power and in an even tinier space, using a one-dimensional edge instead of the two-dimensional plane.

“In physics, edge states often carry a lot of interesting phenomenon, and here, they are the first to turn on. In the future, if we can engineer this material very carefully, then these edges can carry the full current,” Lai says. “We don’t really need the entire thing, because the interior is useless. Just having the edges running to get a current working would substantially reduce the power loss.”

Researchers have been working to get a view into what happens inside a 2-D transistor for years to better understand both the potential and the limitations of the . Getting 2-D transistors ready for commercial devices, such as paper-thin computers and cellphones, is expected to take several more years. Lai says scientists need more information about what interferes with performance in devices made from the new materials.

“These transistors are perfectly two-dimensional,” Lai says. “That means they don’t have some of the defects that occur in a silicon device. On the other hand, that doesn’t mean the new material is perfect.”

Lai and his team used a microscope that he invented and that points microwaves at the 2-D device. Using a tip only 100 nanometers wide, the microwave microscope allowed the scientists to see conductivity changes inside the transistor. Besides seeing the currents’ motion, the scientists found thread-like defects in the middle of the transistors. Lai says this suggests the new material will need to be made cleaner to function optimally.

“If we could make the material clean enough, the edges will be carrying even more current, and the interior won’t have as many defects,” Lai says.

The paper’s other authors are postdoctoral researchers Di Wu and Xiao Li; research scientist Lan Luan, and graduate students Xiaoyu Wu and Zhaodong Chu, and professor Qian Niu in UT Austin’s Department of Physics; and graduate student Wei Li, former graduate student Maruthi N. Yogeesh, postdoctoral researcher Rudresh Ghosh, and associate professor Deji Akinwande of UT Austin’s Department of Electrical and Computer Engineering.

Earlier this year, both Lai and Akinwande won Presidential Early Career Awards for Scientists and Engineers, the U.S. government’s highest honor for early-stage scientists and engineers.

Explore further: Researchers using germanium instead of silicon for CMOS devices

More information: Uncovering edge states and electrical inhomogeneity in MoS2 field-effect transistors, www.pnas.org/cgi/doi/10.1073/pnas.1605982113

 

Read Genesis Nanotech Online: Latest “Nano-News” and Updates


MIT-Convergence_0 070516

Read Today’s Top Stories in Nanotechnology and the ‘Business’ of Nanotechnology. 

Stories about the Discoveries and Technologies that will reshape our world and drive New Economic Engines for the Future.

Read Genesis Nanotechnology Online Here

Stories Like:

Cancer 052716 nanoparticles-nanomedicineHacking metastasis: Nanotechnology researchers find new way to target tumors

 

and …

Canadas-flagCanadian Investors Need to Think Globally to Compete with US Counterparts

 

and much more …

GNT Thumbnail Alt 3 2015-page-001

Genesis Nanotechnology, Inc. ~ “Great Things from Small Things”

Facebook 042616.jpgFollow Us on Facebook

Twitter Icon 042616.jpgUp to the Minute Nanotech News on Our Twitter Feed

LinkedIn IconA 042316.jpg‘Link-Up” with Us on LinkedIn

 Website Icon 042616Connect with Our Website

YouTube small 050516Watch Our YouTube Video 

 

Catalyst efficiency improved for clean industries


Clean Caty 070916 160707151001_1_540x360Mobile platinum oxide species trapped on a cerium oxide surface. The bonding of the platinum to surface oxygens creates isolated platinum atoms that are thermally stable, and active for treatment of automotive exhaust pollutants.
Credit: Washington State University

Researchers have developed a way to use less platinum in chemical reactions commonly used in the clean energy, green chemicals, and automotive industries, according to a paper inScience.

Led by the University of New Mexico in collaboration with Washington State University, the researchers developed a unique approach for trapping platinum atoms that improves the efficiency and stability of the reactions.

Platinum is used as a catalyst in many clean energy processes, including in catalytic converters and fuel cells. The precious metal facilitates chemical reactions for many commonly used products and processes, such as converting poisonous carbon monoxide to less harmful carbon dioxide in catalytic converters.

Because of its expense and scarcity, industries are continually looking to use less of it and to develop catalysts that more efficiently use individual platinum atoms in their reactions. At high temperatures, however, the atoms become mobile and fly together into clumps, which reduces the catalyst’s efficiency and negatively impacts its performance. This is the primary reason why catalytic converters must be tested regularly to ensure they don’t become less effective over time.

“Precious metals are widely used in emission control, but there are always the issues of how to best utilize them and to keep them stable,” said Yong Wang, Voiland Distinguished Professor in the Gene and Linda Voiland School of Chemical Engineering and Bioengineering and a co-author on the paper. “You want to use as little as possible to achieve your objectives, but it’s normally hard to keep the atoms highly dispersed under working conditions.”

The University of New Mexico and WSU research team developed a method to capture the platinum atoms that keeps them stable and lets them continue their catalyzing activity. The researchers used a commonly-used and inexpensive manufacturing material, known as cerium oxide, to create a tiny, nano-scale trap. They shaped the cerium oxide into nanometer-sized rods and polyhedrons, which look like tiny pieces of rock candy, to capture the platinum atoms. With their large surface areas and sufficiently high number of defects, the cerium oxide nano-shapes are able to capture the platinum atoms on their surfaces and keep them from clumping together, so that the platinum can continue to do its work.

“The atom-trapping technique should be broadly applicable for preparing single-atom catalysts,” said Abhaya Datye, a Distinguished Regents’ Professor of Chemical and Biological Engineering at The University of New Mexico, who led the study. “It is remarkable that simply combining the ceria with a platinum catalyst was sufficient to allow trapping of the atoms and retaining the performance of the catalyst.

“Even more surprising is that the process of trapping occurs by heating the catalyst to high temperatures — precisely the conditions used for accelerated aging of these catalysts,” he added.

Adding the cerium oxide to the catalyst is a simple process, too, with no exotic precursors needed.

“This work provides the guiding principles, so that industry can design catalysts to better utilize precious metals and keep them much more stable,” added Wang.


Story Source:

The above post is reprinted from materials provided byWashington State University. The original item was written by Tina Hilding. Note: Materials may be edited for content and length.


Journal Reference:

  1. J. Jones, H. Xiong, A. T. DeLaRiva, E. J. Peterson, H. Pham, S. R. Challa, G. Qi, S. Oh, M. H. Wiebenga, X. I. Pereira Hernandez, Y. Wang, A. K. Datye. Thermally stable single-atom platinum-on-ceria catalysts via atom trapping.Science, 2016; 353 (6295): 150 DOI:10.1126/science.aaf8800

“It’s ALL .. About the WATER! 2 Maps that Show the next Potential Catastrophe Affecting the Middle East: Solving the World’s Water Crisis


World ME Water 070816 screen shot 2016-07-08 at 11.27.43 am

 

As sectarian strife spearheaded by ISIS convulses the Middle East, and tensions between Iran and Saudi Arabia only deepen, it is hard to imagine that a far more pressing concern could be threatening the region.

But a series of maps from the UN show that despite the awful suffering already occurring throughout the Middle East, things could always become significantly worse. The central issue that will affect the region, vast swathes of North and East Africa, and even Central Asia and China is the increasing strain on and lack of the world’s single most important resource — water.

The following map from the UN Water’s 2015 World Water Development Report shows the total amount of renewable water sources per capita available in each country in the world. In 2013, a number of countries — including regional heavyweights such as Saudi Arabia and Jordan — were facing absolute water scarcity.

Egypt, the most populous country in the Middle East, faced water scarcity, as did Syria and Sudan. In Sudan, the lack of water is believed to be one of the root causes of the continuing conflict in the Darfur region as various groups have continued to compete over the increasingly scarce resource.

And the UN predicts that water scarcity will only intensify. By 2030, UN Water predicts that the world will “face a 40% global water deficit under the business-as usual [sic]” scenario. This strain on water, unless proactively addressed, will only cause further inter- and intra-state conflicts.

Again, according to UN Water, “inter-state and regional conflicts may also emerge due to water scarcity and poor management structures. It is noteworthy that 158 of the world’s 263 transboundary water basins lack any type of cooperative management framework.”

Essentially, the world as it currently is will continue to face worse water crises. These crises will force states, or individuals within states, to go to extreme lengths to survive. And without significant frameworks in place, people may resort to conflict for survival.

The following map, from the UN World Water Development Report 2016, shows the proportion of renewable water resources that have already been withdrawn. The Middle East and Central Asia is again at significant risk, as the majority of countries in both regions have withdrawn more than 60% of their water resources.

World Water II 070816 screen shot 2016-07-08 at 11.26.27 am

 

 

Green nature landscape with planet Earth

 

Read More on How New (Nano) Technology Can Help Solve Our Looming Water Issues

MIT Solar Water Power splashMIT: How can we Use Renewable Energy to Solve the Water Crisis – Solar Desalination? (Video)

Published 2015 Water scarcity is a growing problem across the world. John H. Lienhard V and his team at MIT are exploring how to make renewable energy more efficient and affordable. Mechanical engineers and nanotechnologists are looking at different methods, including solar desalination. COMING ~ JUNE 2015 ~ “Great Things from Small Things” ~ Watch […]

Graphene Nano Membrane 071615How Graphene Desalination Could Solve Our Planet’s Water Supply Problems: Video

World WAter Short Map 033016 uci_news_image_downloadNanoscale Desalination of Seawater Through Nanoporous Graphene

Perhaps the most repeated words in the last few years when talking about graphene — since scientists Geim and Novoselov were awarded the Nobel Prize in Physics in 2010 for their groundbreaking experiments — are “the material of the future”. There are some risks regarding so many expectations about everything related to […]

Silver Nano P clean-drinking-water-indiaNanotechnology to provide efficient, inexpensive water desalination