Interdisciplinary team demonstrates superconducting qualities of topological insulators

Topological insulators (TIs) are an exciting new type of material that on their surface carry electric current, but within their bulk, act as insulators. Since the discovery of TIs about a decade ago, their unique characteristics (which point to potential applications in quantum computing) have been explored theoretically, and in the last five years, experimentally. But where in theory, the bulk of TIs carry no current, in the laboratory, impurities and disorder in real materials mean that the bulk is, in fact, conductive. This has proven an obstacle to experimentation with TIs: findings from prior experiments designed to test the surface conductivity of TIs unavoidably included contributions from the surplus of electrons in the bulk. Now an interdisciplinary research team at the University of Illinois at Urbana-Champaign, in collaboration with researchers at Brookhaven National Laboratory’s Condensed Matter Physics and Materials Science Department, has measured superconductive surface states in TIs where the bulk charge carriers were successfully depleted. To deplete the electrons in the bulk, the team used three strategies: the TI material was doped with antimony, then it was doped at the surface with a chemical with strong electron affinity, and finally an electrostatic gate was used to apply voltage that lowered the energy of the entire system.

UD researchers receive additive manufacturing funds

The University of Dayton Research Institute will benefit from the first round of applied research and development project awards the National Additive Manufacturing Innovation Institute announced in a few weeks ago. Rapid Prototype + Manufacturing LLC of Avon Lake, Ohio, was awarded $1 million for “Maturation of Fused Deposition Modeling Component Manufacturing,” and will contract with UD’s Research Institute for $575,000 for technology support and education. Other partners in the program, designed to resolve issues that have inhibited the transition to manufacturing of Fused Deposition Modeling, a popular thermoplastic-based additive process, include Stratasys of Eden Prairie, Minn., as well as aerospace companies Boeing, GE Aviation, Lockheed Martin and Northrop Grumman. “This program allows us to pool resources and leverage highly developed composites industry design practices to mature FDM manufacturing for aerospace and defense applications,” says Brian Rice, head of the Research Institute’s Multi-Scale Composites and Polymers Division. “UDRI’s role will be to analyze material properties and define how to design and certify parts manufactured for aerospace applications.” In July 2012, UDRI received $3 million from the Ohio Third Frontier to work with Stratasys, RP+M and additional partners to develop aircraft-engine components through additive manufacturing —also known as 3D printing—for several aerospace manufacturers.

New research shows ‘perfect twin boundaries’ are not so perfect

Eliminating the defects at the interface separating two crystals, or grains, has been shown by nanotechnology experts to be a powerful strategy for making materials stronger, more easily molded, and less electrically resistant-or a host of other qualities sought by designers and manufacturers. Since 2004, when a seminal paper came out in Science, materials scientists have been excited about one special of arrangement of atoms in metals and other materials called a “coherent twin boundary” or CTB. Based on theory and experiment, these coherent twin boundaries are often described as “perfect,” appearing like a perfectly flat, one-atom-thick plane in computer models and electron microscope images. But new research now shows that coherent twin boundaries are not so perfect after all. A team of scientists at the University of Vermont’s College of Engineering and Mathematical Sciences and the Lawrence Livermore National Laboratory and elsewhere report that coherent twin boundaries found in copper “are inherently defective.” With a high-resolution electron microscope, using a more powerful technique than has ever been used to examine these boundaries, they found tiny kink-like steps and curvatures in what had previously been observed as perfect. Even more surprising, these kinks and other defects appear to be the cause of the coherent twin boundary’s strength and other desirable qualities. “Everything we have learned on these materials in the past 10 years will have to be revisited with this new information,” says UVM engineer Frederic Sansoz.

DOE has issued request for information regarding rotating disk electrode diagnostics for PEMFC electrocatalyst screening

The DOE’s Fuel Cell Technologies Office has issued a request for information seeking feedback from interested stakeholders regarding the use of rotating disk electrode (RDE) experiments and best practices for experimental conditions for characterization of the activity and durability of proton exchange membrane fuel cell oxygen reduction reaction (ORR) electrocatalysts. A review of recent literature shows that the determination of the ORR activity has numerous intricacies that have not been systemically cataloged, resulting in values for the activity of Pt/C that vary significantly. Next steps will be to establish standard procedures and measurement parameters for the RDE technique so that novel catalysts can be benchmarked for ORR activity versus an accepted Pt/C baseline for polymer electrolyte fuel cell applications. DOE is specifically interested in information on best practices/protocols to enable consistency in procedures and less variability in results from different laboratories.

Researchers design nanometer-scale material that can speed up light to “infinitely fast” pace

In a process comparable to squeezing an elephant through a pinhole, researchers at Missouri University of Science and Technology have designed a way to engineer atoms capable of funneling light through ultra-small channels. Their research is the latest in a series of recent findings related to how light and matter interact at the atomic scale, and it is the first to demonstrate that the material—a specially designed “meta-atom” of gold and silicon oxide—can transmit light through a wide bandwidth and at a speed approaching infinity. The meta-atoms’ broadband capability could lead to advances in optical devices, which currently rely on a single frequency to transmit light, the researchers say. ”These meta-atoms can be integrated as building blocks for unconventional optical components with exotic electromagnetic properties over a wide frequency range,” write Jie Gao and Xiaodong Yang, assistant professors of mechanical engineering at Missouri S&T, and Lei Sun, a visiting scholar at the university. The researchers created mathematical models of the meta-atom, a material 100 nanometers wide and 25 nanometers tall that combined gold and silicon oxide in stairstep fashion. In their simulations, the researchers stacked 10 of the meta-atoms, then shot light through them at various frequencies. They found that when light encountered the material in a range between 540 terahertz and 590 terahertz, it “stretched” into a nearly straight line and achieved an “effective permittivity” known as epsilon-near-zero. Effective permittivity refers to the ratio of light’s speed through air to its speed as it passes through a material. As light passes through the engineered meta-atoms described by Gao and Yang, however, its effective permittivity reaches a near-zero ratio. In other words, through the medium of these specially designed materials, light actually travels faster than the speed of light. It travels “infinitely fast” through this medium, Yang says.

Energy Department awards $16M for small businesses focused on energy technologies

Acting Secretary of Energy Daniel Poneman announced that DOE is awarding 88 grants to small businesses in 28 states to develop clean energy technologies with a strong potential for commercialization and job creation. These awards, totaling over $16 million in investments, will help small businesses with promising ideas that could improve manufacturing processes, boost the efficiency of buildings, reduce reliance on foreign oil, and generate electricity from renewable sources. Companies competing for these grants were encouraged to propose outside-the-box innovations to meet ambitious cost and performance targets. The small businesses receiving the awards are located in 28 states: Alabama, Arizona, Arkansas, California, Colorado, Delaware, Florida, Georgia, Illinois, Kentucky, Louisiana, Maryland, Massachusetts, Michigan, Missouri, Montana, Nevada, New Hampshire, New Jersey, New Mexico, New York, Ohio, Pennsylvania, Tennessee, Texas, Utah, Virginia, and Washington. Companies competing for these grants were encouraged to propose outside-the-box innovations to meet ambitious cost and performance targets. The selections are for Phase I and Fast Track (combined Phase I and II) work. That means that the new projects will go toward exploring the feasibility of innovative concepts that could be developed into prototype technologies. Seventy-nine awards will go to SBIR projects, and another nine will go to STTR projects.

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Nature is replete with ingenious structures to make life not just possible, but better. The bony plates of seahorse skeletons, for example, slide past each other, giving the creature incredible flexibility. Materials scientists at the University of California, San Diego, are working to unlock the secrets. Credit: Joanna McKittrick, UCSD.

The Materials Genome Initiative boosted the idea of “materials by design” to the forefront, giving it a name and a cause—reduce the timeline from material discovery to manufacture by half. Without getting into theological or philosophical arguments, Nature may be way ahead of us on executing the idea of materials by design, and the “cause” is simple: survival.

Nature has designed some ingenious materials. Spider thread, for example, has amazing tensile and stretching properties. Abalone shells resist the erosion of ocean floor environments that polish materials with similar compositions into shiny, pretty baubles prized by artists. Why don’t bird beaks break? How is the structure of seahorse spines an advantage?

University of California, San Diego, researchers Marc Meyers and Joanna McKittrick, and Po-Yu Chen, now at National Tsing Hua University, Taiwan—recently wrote a review article in Science (subscription required) on the mechanics of structural biological materials. Specifically, they were looking for the connection between the structure and properties of biological materials, with an eye toward understanding how to engineer similar structures and properties in synthetic materials. Their review focused on three properties: strength under tension, toughness, and resistance to buckling/torsion.

First, they note that there are seven distinguishing characteristics of structural biological materials: self assembly, multifunctionality, hierarchy (different structures at different scales for different purposes), hydration, mild synthesis conditions (low temperature and pressure in aqueous environments), constraints imposed by evolution and environment, and self-healing ability.

Biological materials fall into two broad structural categories: “soft” structures, which are non-mineralized, and “hard” structures, which are composites of minerals and fibrous organic biopolymers. Examples of the former include collagen, keratin, elastin, chitin, lignin, and others. Mineralized composites, the latter group, consist of a mineral reinforcement phase such as hydroxyapatite, calcium carbonate, or siica, embedded in a biopolymer matrix, such as collagen or chitin.

Examples from nature provide insights into the mechanics of structural biological materials. In a press release, McKittrick says, “Mother Nature give us templates. We are trying to understand them better so we can implement them in new materials.”

Besides properties, biological materials have secrets to reveal regarding processing. Exoskeletal animals, like abalones, grow their shells one layer at a time. McKittrick observes in the press release that 3D printing is basically the same concept. “You could build a material similar to the abalone shell using principles we learned from nature by printing layer upon layer of mineral deposits—and do it much faster than nature would.”

Like engineered materials, biological materials bring different properties to the task. “The mechanical behavior of biological constituents and composites is quite diverse,” the authors write. The stress-strain behavior of biominerals, for example, is linear. However, biopolymers behave in a nonlinear fashion, and are key contributors to the high tensile strength of biological materials. Deformation happens first with a stiffening process involving molecular uncoiling and unkinking. After the fibers are fully extended, the polymer backbone stretches and accommodates quite a lot of strain before rupture. Spider silk is a good example of a biopolymer that deforms, yet is strong.

If you are alive, you’ve got to be tough, too. According to the paper, “Toughness is defined as the amount of energy a material absorbs before it fails.” That is, tough materials can deform quite a lot and are strong. They employ several toughening mechanisms that take advantage of the nature of interfaces, for example, by interrupting crack propagation, deflecting cracks, or bridging gaps created by cracks. Examples of tough biological structures include lobster shells, antler bones, abalone nacre, and silica sponge.

Finally, Nature has tricks to share regarding structures that resist bending, torsion, and buckling and the necessary tradeoff between bending and buckling resistance. She does this with thin solid shells filled with lightweight foam or internal struts. This way structural integrity is maximized and the “weight penalty” is minimized. Examples from the plant world include bamboo and the giant bird of paradise stem. The animal world offers structures such as porcupine quills, feathers, and beaks. Skeletal bones, too, are structured with a solid external “cortical bone” sheath filled with a cellular “cancellous bone” core.

Besides structural biological materials, there are other familiar applications of bioinspired materials. For example, most are familiar with the invention of Velcro being inspired by the way plant burrs stuck to animal fur. Olympic sports fans may recall hearing about high-performance swimsuits (eventually banned from competition) that mimic the structure of shark skin and reduce drag in the water. New super-adhesive surgical tapes are designed after gecko foot structure.

“There are a tremendous number of examples of things we can’t do with traditional materials,” McKittrick says in the press release. She admits it will take time, “But they will be better.”

Who better than Mother Nature would know about genomes and design of materials!

If you are attending the PACRIM-GOMD conference in a few weeks, stop by ‘Symposium 23: Advances in Biomineralized Ceramics, Bioceramics, and Bioinstpired Designs,’ which McKittrick and Chen helped organize.

The paper is “Structural Biological Materials: Critical Mechanics-Materials Connections,” by Marc André Meyers, Joanna McKittrick, and Po-Yu Chen. Science, 15 February 2013 (DOI: 10.1126/science.1220854).

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Owens Corning selects Constellation to develop 2.6-megawatt solar project for Delmar, N.Y., facility

Owens Corning and Constellation today announced the development of a 2.6-megawatt solar generation project that will supply clean energy to the company’s thermal and acoustical insulation plant in Delmar, N.Y. Scheduled for completion in late 2013, the solar project is designed to supply more than 6 percent of the plant’s annual electricity needs and will support Owens Corning’s 2020 Environmental Footprint Goals for energy use and greenhouse gas emissions reduction. “The Delmar Plant is committed to environmental sustainability and advancing both our plant and Owens Corning toward our 2020 sustainability goals,” says John Becker, Delmar plant leader for Owens Corning. “In addition, this project is part of our continuing efforts to implement innovative programs that improve and protect New York State’s environment, and have a positive impact on the state’s economy.” Constellation will finance, build, own and maintain the system. Electricity generated by the system will be purchased by Owens Corning under a 20-year power purchase agreement with Constellation.

Energy efficient materials market: New industry research report is now available

A recently added market report by Transparency Market Research on “Energy Efficient Materials Market—Global Industry Size, Share, Trends, Analysis And Forecasts 2012-2018″ is now available. Energy efficient materials are largely used for thermal insulation of buildings as a result of which, demand for these materials is on the rise. Thermal insulation is the most efficient and effective way to improve the energy utilization and efficiency in the building. This method will preserve the indoor heat during winter while keeping the building cool from inside in summers thus improving comfort and saving energy. Some important factors which are necessary for energy saving potential include thermal insulation, efficient lighting system, insulation of windows etc. The most common energy efficient material is fiber glass which is largely used in constructing energy efficient windows. Energy efficient materials industry has a huge market potential in developed countries of America and Europe however, this technology is expected to catch momentum in developing markets of Asia Pacific in near future owing to the increasing adoption of the concept of energy efficient homes. Energy efficient materials market is also driven by increasing consumer demand for operating various appliances and increasing standard of living. In America about 38 percent of total energy consumption is used for heating and cooling purpose in buildings while China accounts for 47.2 percent of total energy consumption.

US Silica exceeds sustainability targets in workplace safety, community investment and environmental protection

U.S. Silica exceeded all of its 2012 Sustainability Targets including those for workplace safety, community investment and environmental protection. The company released its third annual Sustainability Report, Connected, which provides a summary of the company’s goals and accomplishments over the past year. Under the guidance of the company’s Sustainability Council, the 2017 Bold Goals and Annual Targets are focused on three distinct areas: People, Planet and Prosperity. Building off of the company’s last two reports, Connected reflects U.S. Silica’s commitment to employees, neighbors, shareholders and the natural environment. It also underscores U.S. Silica’s leadership in sustainability efforts, ranging from tree plantings and wildlife preservation initiatives to financial and in-kind support for local charities and outreach groups.

EU tariffs aim to prevent Chinese ceramics dumping

(Reuters News) From whitewares to solar panels, ceramic products imported from China are about to become much more expensive for European consumers after the European Commission agreed to impose punitive duties on Chinese ceramic imports to counter what it says is dumping at artificially low prices. Imported Chinese whitewares are now subject to tariffs of between 13.1 and 36.1 percent, according to the EU’s official journal. The European Commission says ceramic tableware and kitchenware imports from China totaled €728 million in 2011. After an investigation of alleged dumping by Chinese producers of €21 billion of solar panels and components, the commission also imposed punitive tariffs of 47 percent on Chinese solar goods and said it is also ready to launch an investigation into Chinese imports of mobile telecom equipment.

NSL Analytical is testing out more space

Growth in industrial markets, more regulations and a shortage of skilled metallurgists all mean the same to NSL Analytical Services Inc.: more business. The independent commercial testing company recently invested more than $1.6 million to buy and renovate a new metallurgical laboratory in Warrensville Heights, Ohio, thus expanding that component of its business. At 11,500 square feet, the new building offers more than double the space of its old metallurgical lab, with more than $560,000 of that investment going to new microscopes, testing machines and other equipment. NSL Analytical, made up of a chemical testing lab and a metallurgical lab, has embarked on an aggressive growth plan in recent years, doubling its revenues and adding 17 employees since 2007, says company president Larry Somrack. He declined to share the company’s annual revenues, but cited the hiring increase as a sign of success. NSL is setting itself up to double its revenue again during the next three years, and Somrack says he plans to hire another 19 employees in the next three to five years. NSL currently has 66 employees. Somrack thinks opportunities exist to support that growth. A rise in regulations in recent years has led to a greater need for outside testing. Also, chief metallurgist Kevin Holland says in an email that he’s seen growth in the oil and gas industry and in manufacturing since the end of the recession.

CoorsTek chief spearheads African ‘impact investing’ fund

After spending years supporting charitable work in Africa, John Coors, chief executive of CoorsTek, the US ceramics manufacturing giant, reached the conclusion that philanthropy was not the answer to fostering economic development. A defining moment came in rural western Kenya about two years ago, when he and a team of doctors and dentists had to turn away lines of people seeking medical help at an orphanage they supported because they could not meet the demand. High quality global journalism requires investment. The experience was the catalyst for Mr Coors to come up with an alternative view, shifting from a charitable approach to capitalism. The result is an initiative that aims to attract investment from influential, wealthy families into a private equity-type fund that has an initial target of raising $300m to invest in sub-Saharan Africa. The One Thousand & One Voices (1K1V) project was launched at the World Economic Forum on Africa in Cape Town with the concept that money would be put to better use if it was invested in growing African businesses and boosting job creation.

3M reports first-quarter results; company posts sales of $7.6B

3M reports first-quarter earnings of $1.61 per share, an increase of 1.3 percent versus the first quarter of 2012. Sales rose 2.0 percent year-on-year to $7.6 billion, an all-time first-quarter record. Organic local-currency sales grew 2.1 percent and acquisitions added 1.7 percent to sales. Currency impacts reduced sales by 1.8 percent year-on-year. Operating income was $1.6 billion and operating income margins for the quarter were 21.6 percent. First-quarter net income was $1.1 billion and free cash flow was $670 million. “We achieved record first-quarter sales and solid operating margins in the face of a low-growth economic environment and the strong U.S. dollar,” said Inge G. Thulin, 3M chair, president and chief executive officer. “At the same time, we further strengthened the company through increased investments in innovation, commercialization and manufacturing.” The company paid $440 million in cash dividends to shareholders and repurchased $805 million of its own shares during the quarter.

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