More Durable – Less Expensive Fuel Cells Speeds the Commercialization of FC Vehicles – U. of Delaware


vehicles-cars-hydrogen-fuel-cellResearchers have developed a new technology that could speed up the commercialization of fuel cell vehicles

Summary: A new technology has been created that could make fuel cells cheaper and more durable. Hydrogen-powered fuel cells are a green alternative to internal combustion engines because they produce power through electro-chemical reactions, leaving no pollution behind. Platinum is the most common catalyst in the type of fuel cells used in vehicles, but it’s expensive. The UD team used a novel method to come up with a less expensive catalyst.

A team of engineers at the University of Delaware has developed a technology that could make fuel cells cheaper and more durable, a breakthrough that could speed up the commercialization of fuel cell vehicles.

They describe their results in a paper published in Nature Communications.

Hydrogen-powered fuel cells are a green alternative to internal combustion engines because they produce power through electrochemical reactions, leaving no pollution behind.

Materials called catalysts spur these electro-chemical reactions. Platinum is the most common catalyst in the type of fuel cells used in vehicles.F Cell Car images

However, platinum is expensive — as anyone who’s shopped for jewelry knows. The metal costs around $30,000 per kilogram.

Instead, the UD team made a catalyst of tungsten carbide, which goes for around $150 per kilogram. They produced tungsten carbide nanoparticles in a novel way, much smaller and more scalable than previous methods.

“The material is typically made at very high temperatures, about 1,500 Celsius, and at these temperatures, it grows big and has little surface area for chemistry to take place on,” said Dionisios Vlachos, director of UD’s Catalysis Center for Energy Innovation.. “Our approach is one of the first to make nanoscale material of high surface area that can be commercially relevant for catalysis.”

The researchers made tungsten carbide nanoparticles using a series of steps including hydrothermal treatment, separation, reduction, carburization and more.

“We can isolate the individual tungsten carbide nanoparticles during the process and make a very uniform distribution of particle size,” said Weiqing Zheng, a research associate at the Catalysis Center for Energy Innovation.

Next, the researchers incorporated the tungsten carbide nanoparticles into the membrane of a fuel cell. Automotive fuel cells, known as proton exchange membrane fuel cells (PEMFCs), contain a polymeric membrane. This membrane separates the cathode from the anode, which splits hydrogen (H2) into ions (protons) and delivers them to the cathode, which puts out current.

The plastic-like membrane wears down over time, especially if it undergoes too many wet/dry cycles, which can happen easily as water and heat are produced during the electrochemical reactions in fuel cells.

When tungsten carbide is incorporated into the fuel cell membrane, it humidifies the membrane at a level that optimizes performance.

“The tungsten carbide catalyst improves the water management of fuel cells and reduces the burden of the humidification system,” said Liang Wang, an associate scientist in the Department of Mechanical Engineering.

The team also found that tungsten carbide captures damaging free radicals before they can degrade the fuel cell membrane. As a result, membranes with tungsten carbide nanoparticles last longer than traditional ones.

“The low-cost catalyst we have developed can be incorporated within the membrane to improve performance and power density,” said . “As a result, the physical size of the fuel cell stack can be reduced for the same power, making it lighter and cheaper. Furthermore, our catalyst is able to deliver higher performance without sacrificing durability, which is a big improvement over similar efforts by other groups.”

The UD research team used innovative methods to test the durability of a fuel cell made with tungsten carbide. They used a scanning electron microscope and focused ion beam to obtain thin-slice images of the membrane, which they analyzed with software, rebuilding the three-dimensional structure of the membranes to determine fuel cell longevity.

The group has applied for a patent and hopes to commercialize their technology.

“This is a very good example of how different groups across departments can collaborate,” Zheng said.

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Materials

provided by University of DelawareNote: Content may be edited for style and length.


Journal Reference:

  1. Weiqing Zheng, Liang Wang, Fei Deng, Stephen A. Giles, Ajay K. Prasad, Suresh G. Advani, Yushan Yan, Dionisios G. Vlachos. Durable and self-hydrating tungsten carbide-based composite polymer electrolyte membrane fuel cellsNature Communications, 2017; 8 (1) DOI: 10.1038/s41467-017-00507-6
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Supercharging Silicon Batteries – Powering Up LI Batteries


super silicon LI batt anode 170906103638_1_540x360
The porosity of the nano-structured Tantalum (in black) enables the formation of silicon channels (in blue) allowing lithium ions to travel faster within the battery. The rigidity of the tantalum scaffold also limits the expansion of the silicon and preserve structural integrity. Credit: Okinawa Institute of Science and Technology Graduate University Nanoparticles by Design Unit

Scientists have designed a novel silicon-based anode to provide lithium batteries with increased power and better stability.

 

As the world shifts towards renewable energy, moving on from fossil fuels, but at the same time relying on ever more energy-gobbling devices, there is a fast-growing need for larger high-performance batteries. Lithium-ion batteries (LIBs) power most of our portable electronics, but they are flammable and can even explode, as it happened to a recent model of smartphone. To prevent such accidents, the current solution is to encapsulate the anode — which is the negative (-) electrode of the battery, opposite to the cathode (+) — into a graphite frame, thus insulating the lithium ions. However, such casing is limited to a small scale to avoid physical collapse, therefore restraining the capacity — the amount of energy you can store — of the battery.

Looking for better materials, silicon offers great advantages over carbon graphite for lithium batteries in terms of capacity. Six atoms of carbon are required to bind a single atom of lithium, but an atom of silicon can bind four atoms of lithium at the same time, multiplying the battery capacity by more than 10-fold. However, being able to capture that many lithium ions means that the volume of the anode swells by 300% to 400%, leading to fracturing and loss of structural integrity. To overcome this issue, OIST researchers have now reported in Advanced Science the design of an anode built on nanostructured layers of silicon — not unlike a multi-layered cake — to preserve the advantages of silicon while preventing physical collapse.

This new battery is also aiming to improve power, which is the ability to charge and deliver energy over time.

“The goal in battery technology right now is to increase charging speed and power output,” explained Dr. Marta Haro Remon, first author of the study. “While it is fine to charge your phone or your laptop over a long period of time, you would not wait by your electric car for three hours at the charging station.”

And when it comes to providing energy, you would want your car to start off quickly at a traffic light or a stop sign, requiring a high spike in power, rather than slowly creeping forward. A well-thought design of a silicone-based anode might be a solution and answer these expectations.img_0132-3

The idea behind the new anode in the Nanoparticles by Design Unit at the Okinawa Institute of Science and Technology Graduate University is the ability to precisely control the synthesis and the corresponding physical structure of the nanoparticles. Layers of unstructured silicon films are deposited alternatively with tantalum metal nanoparticle scaffolds, resulting in the silicon being sandwiched in a tantalum frame.

“We used a technique called Cluster Beam Deposition,” continued Dr. Haro. “The required materials are directly deposited on the surface with great control. This is a purely physical method, there are no need for chemicals, catalysts or other binders.”

“We used a technique called Cluster Beam Deposition,” continued Dr. Haro. “The required materials are directly deposited on the surface with great control. This is a purely physical method, there are no need for chemicals, catalysts or other binders.”

The outcome of this research, led by Prof. Sowwan at OIST, is an anode with higher power but restrained swelling, and excellent cyclability — the amount of cycles in which a battery can be charged and discharged before losing efficiency. By looking closer into the nanostructured layers of silicon, the scientists realized the silicon shows important porosity with a grain-like structure in which lithium ions could travel at higher speeds compared to unstructured, amorphous silicon, explaining the increase in power. At the same time the presence of silicon channels along the Ta nanoparticle scaffolds allows the lithium ions to diffuse in the entire structure. On the other hand, the tantalum metal casing, while restraining swelling and improving structural integrity, also limited the overall capacity — for now.

However, this design is currently only at the stage of proof-of-concept, opening the door to numerous opportunities to improve capacity along with the increased power.

“It is a very open synthesis approach, there are many parameters you can play around,” commented Dr. Haro. “For example, we want to optimize the numbers of layers, their thickness, and replace tantalum metal with other materials.”

With this technique paving the way, it might very well be that the solution for future batteries, forecast to be omnipresent in our lives, will be found in nanoparticles.

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Material provided by Okinawa Institute of Science and Technology (OIST) Graduate UniversityNote: Content may be edited for style and length.

Journal Reference:

  1. Marta Haro, Vidyadhar Singh, Stephan Steinhauer, Evropi Toulkeridou, Panagiotis Grammatikopoulos, Mukhles Sowwan. Nanoscale Heterogeneity of Multilayered Si Anodes with Embedded Nanoparticle Scaffolds for Li-Ion BatteriesAdvanced Science, 2017; 1700180 DOI: 10.1002/advs.201700180

DNA and Nanotechnology: Protein ‘Rebar’ could help make Error-Free Nanostructures: NIST


DNA proteinrebarThe protein RecA (purple units), wraps around and fortifies double-stranded DNA, enabling scientists to build large structures with the genetic material. Credit: NIST

DNA is the stuff of life, but it is also the stuff of nanotechnology. Because molecules of DNA with complementary chemical structures recognize and bind to one another, strands of DNA can fit together like Lego blocks to make nanoscale objects of complex shape and structure.

But researchers need to work with much larger assemblages of DNA to realize a key goal: building durable miniature devices such as biosensors and drug-delivery containers. That’s been difficult because long chains of DNA are floppy and the standard method of assembling long chains is prone to error.

Using a DNA-binding protein called RecA as a kind of nanoscale rebar, or reinforcing bar, to support the floppy DNA scaffolding, researchers at the National Institute of Standards and Technology (NIST) have constructed several of the largest rectangular, linear and other shapes ever assembled from DNA. The structures can be two to three times larger than those built using standard DNA self-assembly techniques.

In addition, because the new method requires fewer chemically distinct pieces to build organized structures than the standard technique, known as DNA origami, it is likely to reduce the number of errors in constructing the shapes. That’s a big plus for the effort to produce reliable DNA-based devices in large quantities, said NIST researcher Alex Liddle.

Although RecA’s ability to bind to double-stranded DNA has been known for years, the NIST team is the first to integrate filaments of this protein into the assembly of DNA structures. The addition of RecA offers a particular advantage: Once one unit of the protein binds to a small segment of double-stranded DNA, it automatically attracts other units to line up alongside it, in the same way that bar magnets will join end-to-end. Like bricks filling out a foundation, RecA lines the entire length of the DNA strand, stretching, widening and strengthening it. A floppy, 2-nanometer-wide strand of DNA can transform into a rigid structure more than four times as wide.

“The RecA method greatly extends the ability of DNA self-assembly methods to build larger and more sophisticated structures,” said NIST’s Daniel Schiffels.

Schiffels, Liddle and their colleague Veronika Szalai describe their work in a recent article in ACS Nano.

The new method incorporates the DNA origami technique and goes beyond it, according to Liddle. In DNA origami, short strands of DNA that have a specific sequence of four base pairs are used as staples to tie together long sections of DNA. To make the skinny DNA skeleton stronger and thicker, the strand may loop back on itself, quickly using up the long string.

If DNA origami is all about the folding, Liddle likened his team’s new method to building a room, starting with a floor plan. The location of the short, single-stranded pieces of DNA that act as staples mark the corners of the room. Between the corners lies a long, skinny piece of single-stranded DNA. The enzyme DNA polymerase transforms a section of the long piece of single-stranded DNA into the double-stranded version of the molecule, a necessary step because RecA only binds strongly to double-stranded DNA. Then RecA assembles all along the double strand, reinforcing the DNA  and limiting the need for extra staples to maintain its shape.

With fewer staples required, the RecA  is likely able to build organized structures with fewer errors than DNA origami, Liddle said.

 Explore further: The promise of nanomanufacturing using DNA origami

More information: Daniel Schiffels et al. Molecular Precision at Micrometer Length Scales: Hierarchical Assembly of DNA–Protein Nanostructures, ACS Nano (2017). DOI: 10.1021/acsnano.7b00320

 

Toward a smart graphene membrane to desalinate water: Penn State University


Graphene H2O towardasmartA scalable graphene-based membrane for producing clean water Credit: Aaron Morelos-Gomez. Credit: Pennsylvania State University

An international team of researchers, including scientists from Shinshu University (Japan) and the director of Penn State’s ATOMIC Center, has developed a graphene-based coating for desalination membranes that is more robust and scalable than current nanofiltration membrane technologies. The result could be a sturdy and practical membrane for clean water solutions as well as protein separation, wastewater treatment and pharmaceutical and food industry applications.

“Our dream is to create a smart  that combines high flow rates, high efficiency, long lifetime, self-healing and eliminates bio and inorganic fouling in order to provide clean water solutions for the many parts of the world where clean water is scarce,” says Mauricio Terrones, professor of physics, chemistry and materials science and engineering, Penn State. “This work is taking us in that direction.”

The hybrid membrane the team developed uses a simple spray-on technology to coat a mixture of graphene oxide and few-layered graphene in solution onto a backbone support membrane of polysulfone modified with polyvinyl alcohol. The support membrane increased the robustness of the hybrid membrane, which was able to stand up to intense cross-flow, high pressure and chlorine exposure. Even in early stages of development, the membrane rejects 85 percent of salt, adequate for agricultural purposes though not for drinking, and 96 percent of dye molecules. Highly polluting dyes from textile manufacturing is commonly discharged into rivers in some areas of the world.

Chlorine is generally used to mitigate biofouling in membranes, but chlorine rapidly degrades the performance of current polymer membranes. The addition of few-layer graphene makes the new membrane highly resistant to chlorine.

Graphene is known to have high mechanical strength, and porous graphene is predicted to have 100 percent salt rejection, making it a potentially ideal material for desalination membranes. However, there are many challenges with scaling up graphene to industrial quantities including controlling defects and the need for complex transfer techniques required to handle the two-dimensional material. The current work attempts to overcome the scalability issues and provide an inexpensive, high quality membrane at manufacturing scale.

The work was performed in the Global Aqua Innovation Center and the Institute of Carbon Science and Technology at Shinshu University, Nagano, Japan, where Terrones is also a Distinguished Invited Professor. The team includes researchers Aaron Morelos-Gomez, Josue Ortiz-Medina and Rodolfo Cruz-Silva, former Ph.D. students of Terrones. Morelos-Gomez is lead author on a paper published online on August 28 in Nature Nanotechnology describing their work titled “Effective NaCL and dye rejection of hybrid graphene oxide/graphene layered membranes.” The Japanese researchers, Hiroyuki Muramatsu, Takumi Araki, Tomoyuki Fukuyo, Syogo Tejima, Kenji Takeuchi, and Takuya Hayashi, were also led by Professor Morinobu Endo.

First author Aaron Morelos-Gomez says, “Our membrane overcomes the water solubility of graphene oxide by using polyvinyl alcohol as an adhesive making it resistant against strong water flow and high pressures. By mixing  with  we could also improve significantly its chemical resistance.”

Professor Morinobu Endo concludes that “this is the first step towards more effective and smart membranes that could self-adapt depending on their environment.”

 Explore further: Graphene sieve turns seawater into drinking water

More information: Aaron Morelos-Gomez et al. Effective NaCl and dye rejection of hybrid graphene oxide/graphene layered membranes, Nature Nanotechnology (2017). DOI: 10.1038/nnano.2017.160

Read more at: https://phys.org/news/2017-09-smart-graphene-membrane-desalinate.html#jCp

Read more at: https://phys.org/news/2017-09-smart-graphene-membrane-desalinate.html#jCp

Silicon Solves Problems for next-Generation Battery Technology: University of Eastern Finland


Silicon in New LI Batts 170830114817_1_540x360

Silicon — the second most abundant element in the earth’s crust — shows great promise in Li-ion batteries, according to new research from the University of Eastern Finland. By replacing graphite anodes with silicon, it is possible to quadruple anode capacity.

In a climate-neutral society, renewable and emission-free sources of energy, such as wind and solar power, will become increasingly widespread. The supply of energy from these sources, however, is intermittent, and technological solutions are needed to safeguard the availability of energy also when it’s not sunny or windy. Furthermore, the transition to emission-free energy forms in transportation requires specific solutions for energy storage, and lithium-ion batteries are considered to have the best potential.

Researchers from the University of Eastern Finland introduced new technology to Li-ion batteries by replacing graphite used in anodes by silicon. The study analysed the suitability of electrochemically produced nanoporous silicon for Li-ion batteries. It is generally understood that in order for silicon to work in batteries, nanoparticles are required, and this brings its own challenges to the production, price and safety of the material.

However, one of the main findings of the study was that particles sized between 10 and 20 micrometres and with the right porosity were in fact the most suitable ones to be used in batteries. The discovery is significant, as micrometre-sized particles are easier and safer to process than nanoparticles. This is also important from the viewpoint of battery material recyclability, among other things. The findings were published in Scientific Reports.

“In our research, we were able to combine the best of nano- and micro-technologies: nano-level functionality combined with micro-level processability, and all this without compromising performance,” Researcher Timo Ikonen from the University of Eastern Finland says. “Small amounts of silicon are already used in Tesla’s batteries to increase their energy density, but it’s very challenging to further increase the amount,” he continues.

Next, researchers will combine silicon with small amounts of carbon nanotubes in order to further enhance the electrical conductivity and mechanical durability of the material.

“We now have a good understanding of the material properties required in large-scale use of silicon in Li-ion batteries. However, the silicon we’ve been using is too expensive for commercial use, and that’s why we are now looking into the possibility of manufacturing a similar material from agricultural waste, for example from barley husk ash,” Professor Vesa-Pekka Lehto explains.

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Materials

provided by University of Eastern FinlandNote: Content may be edited for style and length.

NREL, Swiss Scientists Power Past Solar Efficiency Records


NREL scientist Adele Tamboli, co-author of a recent article on silicon-based multijunction solar cells, stands in front of an array of solar panels. Credit: Dennis Schroeder

August 25, 2017




Second collaborative effort proves silicon-based multijunction cells that reach nearly 36% efficiency

Collaboration between researchers at the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL), the Swiss Center for Electronics and Microtechnology (CSEM), and the École Polytechnique Fédérale de Lausanne (EPFL) shows the high potential of silicon-based multijunction solar cells.

The research groups created tandem solar cells with record efficiencies of converting sunlight into electricity under 1-sun illumination. The resulting paper, “Raising the One-Sun Conversion Efficiency of III–V/Si Solar Cells to 32.8% for Two Junctions and 35.9% for Three Junctions,” appears in the new issue of Nature Energy. Solar cells made solely from materials in Groups III and V of the Periodic Table have shown high efficiencies, but are more expensive.

Stephanie Essig, a former NREL post-doctoral researcher now working at EPFL in Switzerland, is lead author of the newly published research that details the steps taken to improve the efficiency of the multijunction cell. While at NREL, Essig co-authored “Realization of GaInP/Si Dual-Junction Solar Cells with 29.8% 1-Sun Efficiency,” which was published in the IEEE Journal of Photovoltaics a year ago.

In addition to Essig, authors of the new research paper are Timothy Remo, John F. Geisz, Myles A. Steiner, David L. Young, Kelsey Horowitz, Michael Woodhouse, and Adele Tamboli, all with NREL; and Christophe Allebe, Loris Barraud, Antoine Descoeudres, Matthieu Despeisse, and Christophe Ballif, all from CSEM.

“This achievement is significant because it shows, for the first time, that silicon-based tandem cells can provide efficiencies competing with more expensive multijunction cells consisting entirely of III-V materials,” Tamboli said. “It opens the door to develop entirely new multijunction solar cell materials and architectures.”

In testing silicon-based multijunction solar cells, the researchers found that the highest dual-junction efficiency (32.8%) came from a tandem cell that stacked a layer of gallium arsenide (GaAs) developed by NREL atop a film of crystalline silicon developed by CSEM. An efficiency of 32.5% was achieved using a gallium indium phosphide (GaInP) top cell, which is a similar structure to the previous record efficiency of 29.8% announced in January 2016. 

A third cell, consisting of a GaInP/GaAs tandem cell stacked on a silicon bottom cell, reached a triple-junction efficiency of 35.9%—just 2% below the overall triple-junction record.

The existing photovoltaics market is dominated by modules made of single-junction silicon solar cells, with efficiencies between 17% and 24%. 

The researchers noted in the report that making the transition from a silicon single-junction cell to a silicon-based dual-junction solar cell will enable manufacturers to push efficiencies past 30% while still benefiting from their expertise in making silicon solar cells.

The obstacle to the adoption of these multijunction silicon-based solar cells, at least in the near term, is the cost. Assuming 30% efficiency, the researchers estimated the GaInP-based cell would cost $4.85 per watt and the GaAs-based cell would cost $7.15 per watt. 

But as manufacturing ramps up and the efficiencies of these types of cells climbs to 35%, the researchers predict the cost per watt could fall to 66 cents for a GaInP-based cell and to 85 cents for the GaAs-based cell. 

The scientists noted that such a precipitous price drop is not unprecedented; for instance, the cost of Chinese-made photovoltaic modules fell from $4.50 per watt in 2006 to $1 per watt in 2011.

The cost of a solar module in the United States accounts for 20% to 40% of the price of a photovoltaic system. Increasing cell efficiency to 35%, the researchers estimated, could reduce the system cost by as much as 45 cents per watt for commercial installations. 

However, if the costs of a III-V cell cannot be reduced to the levels of the researchers’ long-term scenario, then the use of cheaper, high-efficiency materials for the top cell will be needed to make them cost-competitive in general power markets.

The funding for the research came from the Energy Department’s SunShot Initiative—which aims to make solar energy a low-cost electricity source for all Americans through research and development efforts in collaboration with public and private partners—and from the Swiss Confederation and the Nano-Tera.ch initiative.


NREL is the U.S. Department of Energy’s primary national laboratory for renewable energy and energy efficiency research and development. NREL is operated for the Energy Department by The Alliance for Sustainable Energy, LLC.

We May Finally Have a Way to Cheaply Manufacture Pure Graphene


Synthesizing Pure Graphene




Researchers have been singing the praises of graphene ever since it was first isolated from graphite back in 2004. That’s not terribly surprising given the unique properties the two-dimensional material possesses. Graphene has since proven useful for everything from superconductors to microchips to tougher-than-steel rubber bands, but despite the wealth of research, manufacturing graphene for large-scale commercial use has remained problematic — the process is simply too costly and complicated.

University of Connecticut chemistry professor Doug Adamson might be able to change that. He and his colleagues have figured out a cost-effective way to synthesize this wonder material, and perhaps best of all, Adamson claims his method synthesizes graphene in its pure, unoxidized form. The research has been published in ACS Nano.

Watch More: Super Materials of Tomorrow – Graphene

Adamson’s method takes advantage of one of graphene’s typically undesirable characteristics: its insolubility to most solvents. After placing graphite in an interface of water and oil, the material spreads spontaneously to cover the interface. There, it becomes trapped in individual, overlapping graphene sheets that can be locked in place using plastic or other cross-linked polymers.

“The innovation and technology behind our material is our ability to use a thermodynamically driven approach to un-stack graphite into its constituent graphene sheets, and then arrange those sheets into a continuous, electrically conductive, three-dimensional structure,” Adamson explained in a UConn press release.


Its Best Behavior

The “graphene” most researchers use in their studies is an oxidized version of the material. Adding oxygen to graphene makes it easier to work with, but it also increases the cost, requires the use of hazardous materials, and adds time to the manufacturing process. It also reduces graphene’s mechanical, thermal, and electrical properties — essentially what makes graphene great.

“The simplicity of our approach is in stark contrast to current techniques used to exfoliate graphite that rely on aggressive oxidation or high-energy mixing or sonication — the application of sound energy to separate particles — for extended periods of time,” Adamson said. “As straightforward as our process is, no one else had reported it. We proved it works.”

Now that Adamson’s team has found a way to produce this pristine graphene, they’re looking forward to potential applications. One of those is desalination. The group created a startup, 2D Material Technologies, that is working on a device that uses their pure graphene and a process known as capacitive deionization (CDI) to remove salt from brackish water.

While much has already been accomplished using graphene, a technique like Adamson’s that can easily be scaled up for the mass production of the material could lead to an explosion of new research and commercial applications. A bit more than a decade after its discovery, all the wonder of graphene could finally be taken advantage of in a meaningful way.

Cummins Beats Tesla To The Punch And Introduces An All-Electric Heavy-Duty Truck



With Tesla purportedly gearing up to introduce an all-electric semi next month, diesel engine supplier Cummins took some of the automaker’s buzz away on Tuesday, revealed an all-electric prototype truck of its own.

Read More: Here’s More Reasons Why We Need Electric Trucks




Billed as a Class 7 Urban Hauler Tractor, the 18,000-pound truck was built by Roush and is geared for local deliveries, according to the Indianapolis Star. The company said it plans to begin selling a 140 kWh battery pack for bus operators and commercial truck fleets in 2019, reports Forbes.

With a claimed range of 100 miles, it certainly seems apt to handle short drives, and Cummins said it only takes an hour to charge. By the time it’s introduced in 2020, Forbes reports, the company hopes to drop that number to 20 minutes. 

A hybrid, with a diesel engine used on-board as a generator, is planned later and will offer 300 miles in range.

Cummins’ chief exec, Thomas Linebarger, told Forbes that electric technology isn’t quite ready for 18-wheelers, mostly due to the long distances they travel. Tesla’s truck will reportedly be set to handle lengthier tasks, with 200 to 300 miles on a single charge, but that remains far below the 1,000 miles a typical heavy-duty truck can handle on one tank of gas.

Cummins may have introduced a prototype truck cab to show off, but the company only intends to produce the powertrain for trucks, Forbes reports.

Nanotechnology delivers medicine to cancer cells while protecting healthy cells ~ “Fooling Cancer”



Cancer treatments, including chemotherapy, have helped many of those who have been diagnosed with the disease to go on to live healthy lives.

Nevertheless, chemotherapy takes a toll on the body. During treatment, chemotherapy attacks all of the body’s cells, not just cancer cells. The result destroys healthy cells, causing many patients to suffer major side effects during and after treatment.

And because current treatments aren’t specifically targeted to cancer cells, only 0.01 percent of chemotherapy drugs actually reach the tumor and its diseased cells.

“I’m working on figuring out how we can deliver more of the chemotherapy drugs to the tumor and less to healthy cells,” says Sofie Snipstad, who recently graduated from the Department of Physics at the Norwegian University of Science and Technology (NTNU). Last year, she won a Norwegian science communication competition for PhD candidates called Researcher Grand Prix. When she made her winning presentation about her research during the competition finals, she was in the middle of testing a new method of cancer treatment on mice.

Now her research has shown that the method can cure cancer in mice.

Her study has just been published in the academic journal Ultrasound in Medicine and Biology (“Ultrasound Improves the Delivery and Therapeutic Effect of Nanoparticle-Stabilized Microbubbles in Breast Cancer Xenografts”).


Blood vessels supplying the cancer cells (kreftceller in the illustration) have porous walls, while the sections of blood vessels passing through healthy cells are not porous. This protects healthy cells from the chemotherapy. (Image: NTNU)

Promising results

Snipstad’s method targets cancerous tumors with chemotherapy so that more of the drug reaches cancer cells while protecting healthy cells. The experiments were conducted in mice with an aggressive breast cancer type (triple negative).

Researchers undertook many laboratory experiments before conducting their tests with mice — which were the first actual tests using this delivery method for chemotherapy. In addition to causing the tumors to disappear during treatment, the cancer has not returned in the trial animals.

“This is an exciting technology that has shown very promising results. That the first results from our tests in mice are so good, and that the medicine does such a good job right from the start is very promising,” Snipstad says.

Here’s how the treatment works

Instead of being injected straight into the bloodstream and transported randomly to both sick and healthy cells, the chemotherapy medicine is encapsulated in nanoparticles. When nanoparticles containing the cancer drugs are injected into the bloodstream, the nanoparticles are so large that they remain in the blood vessels in most types of healthy tissues. This prevents the chemotherapy from harming healthy cells.

Blood vessels in the tumor, however, have porous walls, so that the nanoparticles containing the chemotherapy can work their way into the cancerous cells.

“My research shows that this method allows us to supply 100 times more chemotherapy to the tumor compared to chemotherapy alone. That’s good,” Snipstad says.

However, the nanoparticles can only reach cells that are closest to the blood vessels that carry the drug-laden particles, she said. That means that cancer cells that are far from the blood vessels that supply the tumour do not get the chemotherapy drugs.

“For the treatment to be effective, it has to reach all parts of the tumor. So our nanoparticles need help to deliver the medicine,” she said.

Ultrasound is the key

The nanoparticles used by Snipstad and her research team were developed at SINTEF in Trondheim. SINTEF is one of Europe’s largest independent research organizations. The particles are unusual because they can form small bubbles. The nanoparticles are in the surface of the bubbles.

These bubbles are an important part of the cancer treatment. Another essential part is the use of ultrasound, which is Snipstad’s area of research.

nanobubbles in ultrasound treatments

To make the bubbles behave the way they wanted, the researchers tested many different ultrasound treatments, and measured how many of the nanoparticles were delivered to cancerous tissues in mice. Many of the ultrasound treatments had little effect, but Sofie Snipstad found one that worked quite well. (Image: NTNU)

The bubbles that contain the chemotherapy-laden nanoparticles are injected into the bloodstream. Ultrasound is then applied to the tumor. The ultrasound causes the bubbles to vibrate and eventually burst, so that the nanoparticles are released. The vibrations also massage the blood vessels and tissues to make them more porous. 

This helps push the nanoparticles further into the cancerous tumor, instead of only reaching the cancer cells closest to the blood vessels.

“By using ultrasound to transport the chemotherapy-laden nanoparticles into the tumors, our research on mice has shown that we can deliver about 250 times more of the drug to the tumor compared to just injecting chemotherapy into the bloodstream alone,” she says.

Three groups, three clear results

The mice were divided into three groups:

Group 1 received no treatment, and the tumor continued to grow.

Group 2 received the treatment using drug-laden nanoparticles. The growth of the tumor stagnated after time, but the tumour did not disappear.

Group 3 received the treatment using drug-laden nanoparticles, bubbles and ultrasound. In this group, the tumor shrank until it disappeared. One hundred days after the treatment was discontinued, the mice were still cancer-free.

Fooling cancer cells

“For the treatment to be effective, we have to trick the cancer cells to take up the nanoparticles so that the chemotherapy reaches its target,” Snipstad says.

To study this process, she has grown cancer cells and examined them under a microscope. Here, she has seen that the nanoparticles camouflage the chemotherapy drug, allowing the cancer cells to take them up. But for the treatment to work, the nanoparticles have to release the cancer drug exactly when and where it is needed.

“We can do that by changing the chemical composition of the nanoparticles so that we can tailor properties, including determining how quickly the nanoparticles break down. After the cell takes up the nanoparticle, the nanoparticle dissolves and releases the cancer drug inside the cell. That causes the cancer cell to stop dividing, and it will eventually shrink and die.

Close interdisciplinary cooperation

NTNU physics professor Catharina Davies heads the research group of which Snipstad is part. The group mainly works with nanoparticles.

The NTNU group works closely with SINTEF and St. Olavs Hospital in Trondheim. NTNU conducts the animal tests and studies the cancer cells. SINTEF has developed the bubbles containing nanoparticles, which provides the research platform. The cancer clinic and ultrasound group at St. Olavs contribute with their clinical skills.

“One of the things that I like about this project is that so many good people with different backgrounds are involved. Trondheim has a very good interdisciplinary environment, and this project needs all of these different disciplines for us to make progress,” Snipstad said.

No human trials anytime soon

While research results are very promising, it will still be some time before the method can be used in humans.

“It can take from 10-20 years from the time a discovery is made in the lab until it can be used as a treatment,” Snipstad said. “We’ve been working on this about six years, so we still have a lot to learn. 
We need to understand more about the mechanisms behind our success and we have to do much more work using microscopes to understand what is happening inside the tissues.”

Snipstad said that the find also has researchers excited to test the method on other types of cancers, because each type of cancer is different.

Possible treatment for brain cancer

This combination of bubbles, nanoparticles and ultrasound also opens the door on the possibility of treating brain diseases. The brain is protected by a special blood-brain barrier, which makes it difficult to deliver drugs to the brain for treatment. This barrier allows only substances that the brain needs to pass through the barrier, which means that for many brain diseases, there is no treatment whatsoever.

“But there is hope. By using ultrasound and our bubbles we have managed to deliver nanoparticles and drugs to the brain. This may be promising for the treatment of cancer and other diseases in the brain,” Snipstad said.

Source: Norwegian University of Science and Technology

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“Stretch-ee” Gold Nanoclusters for Wearable Electronics 



Researchers have fabricated highly deformable and stretchable conductors utilizing a Coil Flash Thermal Evaporation (CFTE) of gold nanoclusters that form robust thin metallic layers and maintain conductivity up to 200% on PDMS and 150% on textured rubber.

The CFTE method is known to produce gold nanoclusters with low ionization and kinetic energies, which minimizes carbonization of elastomers during deposition.

As the researchers report in ACS Applied Materials & Interfaces (“Facile Fabrication of Ultra-Stretchable Metallic Nanocluster Films for Wearable Electronics”), high metal-elastomer adhesion is obtained with textured substrates.


(a) Schematics showing the formation of low energy gold nanoclusters incident on stretchable elastomers. (b) TEM image of the deposited nanoclusters during the early stages of cluster coalescence. The green arrows show some of the deposited nanoclusters having a grainy morphology on a background of coalesced clusters. Scale bar-20 nm (c) The size distribution of the metal nanoclusters is shown along with a Normal fit (average cluster size ∼3.7 nm). (d) Shows the setup with eutectic liquid alloy contacts used for measurements. The discontinuity regions and the method to map them is shown. (e) Shows the change in resistance R(x) along the sample length for 25% and 70% strained samples emphasizing the discontinuity effect. Axes: (25% Bottom-Left and 70% Top-Right). (© 

The CFTE-gold films on textured substrates are highly robust and perform significantly better than e-beam, sputtered and implanted electrodes and exhibit only a small increase in resistance with strain (25 Ω-sq-1 at 100% strain).

The films stretch and relax in a bellow type open-and-close mechanism which allow for a robust performance with cyclic straining.

The CFTE is a one-step low vacuum process (0.5 × 10-2 millibar), not requiring intensive fabrication setups and large processing durations associated with other vapor deposition based processes.

The authors point out that the facile nature of this process opens up possibilities for easy incorporation of these electrodes for various functionalities involving deformable electronics like textile electronics, biointerfacing of devices, lab-on-chip devices, robotics, and stretchable metallic interconnects.

“Low cost and high throughput should make it possible to easily facilitate the integration of this process into numerous industrial production lines and clean room fabrication setups for ubiquitous electronics,” they conclude their report.

By Michael Berger – Michael is author of two books by the Royal Society of Chemistry: Nano-Society: Pushing the Boundaries of Technology and Nanotechnology: The Future is Tiny.