An impact resistance and fatigue-testing study reports that Telene, a thermoset polydicyclopentadiene (PDCPD), used as a matrix in a glass fiber composite, demonstrated improved impact strength and fatigue resistance for products subject to high stress factors. The study, released by the Department of Materials Engineering at the University of Leuven, Belgium, found that Telene exhibited 50% greater resistance in impact testing and four times longer life in fatigue testing than epoxy samples did, while maintaining the same overall tensile strength. The study compared Telene alongside an equivalent epoxy composite commonly used in the laminate process. While the epoxy-based laminates used with glass fibers exhibited revealed early local damage and loss of mechanical properties, Telene reportedly retained its mechanical characteristics throughout the extended testing protocol, until break. An abstract and the full study are available from Science Direct. This story is reprinted from material from Telene, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.
Abstract: Washington State University researchers have developed a novel nanomaterial that could improve the performance and lower the costs of fuel cells by using fewer precious metals like platinum or palladium. Led by Yuehe Lin, professor in the School of Mechanical and Materials Engineering, the researchers used inexpensive metal to make a super low density material, called an aerogel, to reduce the amount of precious metals required for fuel cell reactions. They also sped up the time to make the aerogels, which makes them more viable for large-scale production. Their work is published in Advanced Materials. Hydrogen fuel cells are a promising green energy solution, producing electricity much more efficiently and cleanly than combustion engines. But they need expensive precious metals to fuel their chemical reactions. This need has limited their acceptance in the marketplace. Aerogels, which are sometimes also called liquid smoke, are solid materials that are about 92 percent air. Effective insulators, they are used in wet suits, firefighting gear, windows, paints and in fuel cell catalysts. Because metal-based aerogels have large surface areas and are highly porous, they work well for catalyzing in fuel cells. The WSU team created a series of bimetallic aerogels, incorporating inexpensive copper and using less precious metal than other metal aerogels. Researchers introduced the copper in the bimetallic system through their new, one-step reduction method to create hydrogel. The hydrogel is the liquid-filled form of aerogel. The liquid component is carefully and completely dried out of the hydrogel to create aerogel. Their method has reduced the manufacturing time of hydrogel from three days to six hours. "This will be a great advantage for large scale production," said Chengzhou Zhu, a WSU assistant research professor who created the aerogel. 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. For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.
ASM Fellow Richard D. Sisson has received Worcester Polytechnic Institute's 2016 Board of Trustees' Award for Outstanding Research and Creative Scholarship. The award recognizes continuing excellence in research and scholarship by faculty members over a period of at least five years. Prof. Sisson is the George F. Fuller Professor of Mechanical Engineering, director of Worcester Polytechnic Institute's Manufacturing and Materials Engineering Programs, and technical director of the WPI Center for Heat Treating Excellence. He is internationally recognized for his research in materials science and engineering, as well as manufacturing. His pioneering work spans several areas of physical metallurgy, and he has written more than 250 journal articles and 250 technical presentations. Prof. Sisson is currently principal investigator for a multi-million-dollar, multi-institution project aimed at developing new metallurgical methods and new lightweight alloys to help the military build more effective and durable vehicles and systems. He has won numerous national and international awards, and has served as president of the ASM Heat Treating Society.
Pollens, the bane of allergy sufferers, could represent a boon for battery makers: Recent research has suggested their potential use as anodes in lithium-ion batteries. "Our findings have demonstrated that renewable pollens could produce carbon architectures for anode applications in energy storage devices," says Vilas Pol, an associate professor in the School of Chemical Engineering and the School of Materials Engineering at Purdue University. Batteries have two electrodes, called an anode and a cathode. The anodes in most of today's lithium-ion batteries are made of graphite. Lithium ions are contained in a liquid called an electrolyte, and these ions are stored in the anode during recharging. The researchers tested bee pollen- and cattail pollen-derived carbons as anodes. "Both are abundantly available," says Pol, who worked with doctoral student Jialiang Tang. "The bottom line here is we want to learn something from nature that could be useful in creating better batteries with renewable feedstock." Research findings are detailed in a paper that appears today in Nature's Scientific Reports. Whereas bee pollen is a mixture of different pollen types collected by honeybees, the cattail pollens all have the same shape. "I started looking into pollens when my mom told me she had developed pollen allergy symptoms about two years ago," Tang says. "I was fascinated by the beauty and diversity of pollen microstructures. But the idea of using them as battery anodes did not really kick in until I started working on battery research and learned more about carbonization of biomass." The researchers processed the pollen under high temperatures in a chamber containing argon gas using a procedure called pyrolysis, yielding pure carbon in the original shape of the pollen particles. They were further processed, or "activated," by heating at lower temperature — about 300 C — in the presence of oxygen, forming pores in the carbon structures to increase their energy-storage capacity. The research showed the pollen anodes could be charged at various rates. While charging for 10 hours resulted in a full charge, charging them for only one hour resulted in more than half of a full charge, Pol says. "The theoretical capacity of graphite is 372 milliamp hours per gram, and we achieved 200 milliamp hours after one hour of charging," he says. The researchers tested the carbon at 25 C and 50 C to simulate a range of climates. "This is because the weather-based degradation of batteries is totally different in New Mexico compared to Indiana," Pol says. Findings showed the cattail pollens performed better than bee pollen. The work is ongoing. Whereas the current work studied the pollen in only anodes, future research will include work to study them in a full-cell battery with a commercial cathode. "We are just introducing the fascinating concept here," Pol says. "Further work is needed to determine how practical it might be." Electron microscopy studies were performed at the Birck Nanotechnology Center in Purdue's Discovery Park. The work was supported by Purdue's School of Chemical Engineering. The electron microscopy studies at Birck were funded by a Kirk exploratory research grant and were conducted by doctoral students Arthur D. Dysart and Vinodkumar Etacheri. An XPS measurement was conducted by Dmitry Zemlyanov at Birck. Other support came from the Hoosier Heavy Hybrid Center of Excellence (H3CoE) fellowship, funded by U.S. Department of Energy. Release Date: February 5, 2016 Source: Purdue University
News Article | April 7, 2016
Carbon fibers derived from a sustainable source, a type of wild mushroom, and modified with nanoparticles have been shown to outperform conventional graphite electrodes for lithium-ion batteries. Researchers at Purdue University have created electrodes from a species of wild fungus called Tyromyces fissilis. "Current state-of-the-art lithium-ion batteries must be improved in both energy density and power output in order to meet the future energy storage demand in electric vehicles and grid energy-storage technologies," says Vilas Pol, an associate professor in the School of Chemical Engineering and the School of Materials Engineering. "So there is a dire need to develop new anode materials with superior performance." Batteries have two electrodes, called an anode and a cathode. The anodes in most of today's lithium-ion batteries are made of graphite. Lithium ions are contained in a liquid called an electrolyte, and these ions are stored in the anode during recharging. Pol and doctoral student Jialiang Tang have found that carbon fibers derived from Tyromyces fissilis and modified by attaching cobalt oxide nanoparticles outperform conventional graphite in the anodes. The hybrid design has a synergistic result, Pol says. "Both the carbon fibers and cobalt oxide particles are electrochemically active, so your capacity number goes higher because they both participate," he says. The hybrid anodes have a stable capacity of 530 milliamp hours per gram, which is one and a half times greater than graphite's capacity. Findings are detailed in a paper appearing online in the American Chemical Society's Sustainable Chemistry & Engineering journal. One approach for improving battery performance is to modify carbon fibers by attaching certain metals, alloys or metal oxides that allow for increased storage of lithium during recharging. Tang got the idea of tapping fungi for raw materials while researching alternative sources for carbon fibers. "The methods now used to produce carbon fibers for batteries are often chemical heavy and expensive," Tang says. He noticed a mushroom growing on a rotting wood stump in his backyard and decided to study its potential as a source for carbon fibers. "I was curious about the structure so I cut it open and found that it has very interesting properties," he says. "It's very rubbery and yet very tough at the same time. Most interestingly, when I cut it open it has a very fibrous network structure." Comparisons with other fungi showed the Tyromyces fissilis was especially abundant in fibers. The fibers are processed under high temperatures in a chamber containing argon gas using a procedure called pyrolysis, yielding pure carbon in the original shape of the fungus fibers. The fibers have a disordered arrangement and intertwine like spaghetti noodles. The interconnected network brings faster electron transport, which could result in faster battery charging. Electron microscopy studies were performed at the Birck Nanotechnology Center in Purdue's Discovery Park. The work was supported by Purdue's School of Chemical Engineering. The electron microscopy studies at Birck were funded by a Kirk exploratory research grant and were conducted by former postdoctoral research associate Vinodkumar Etacheri.