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National Nanomanufacturing Network
InterNano is an open-source online information clearinghouse for the nanomanufacturing research and development (R&D) community in the United States. It is designed provide this community with an array of tools and collections relevant to its work and to the development of viable nanomanufacturing applications.
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Recent announcements by the federal government identifying the next rounds of Manufacturing Innovation Institutes (MIIs) have selected topics for public-private funding opportunities that potentially provide opportunity for nanomaterials and nanomanufacturing technologies. The selected topics, which include $200M in public-private funding for an Integrated Photonics Institute (IP) (http://manufacturing.gov/ip-imi.html), and $150M a Flexible Hybrid Electronics (FHE) Institute (http://www.manufacturing.gov/fhe-mii.html), each have critical aspects enabled through nanotechnology. Flexible hybrid electronics inherently incorporate printed electronics that involve the processing of various inks containing nanomaterials, such as carbon nanotubes, graphene, or metallic and metal oxide nanoparticles. Similarly integrated photonics exploit innovative materials and processes in order to create integrated optical or photonic devices and systems utilizing nanostructures and nanoscale patterning techniques. Flexible Hybrid Electronics are enabled through innovative manufacturing processes adapted from traditional industry approaches that preserve the full operation of traditional electronic circuits in flexible architectures. The technology demonstrators for manufacturability are intended to exhibit novel flexible form factors that are conformal, bending, stretching, or folding, and address a range of emerging applications in human activity and health monitoring, ubiquitous sensors (i.e.; the Internet of Things), or wearable electronics. The manufacturing institute will address issues including standards, materials, process scale-up, design tools, and advanced manufacturing. The Integrated Photonics Manufacturing Institute will focus on developing an end-to-end photonics ecosystem in the U.S., including domestic foundry access, integrated design tools, automated packaging, assembly and test, and workforce development. The manufacturing innovation institute will serve as a regional hub, bridging the gap between applied research and product development by bringing together companies, universities, and other academic and training institutions and Federal agencies to co-invest in key technology areas that encourage investment and production in the U.S.
Researchers create silicon nanofibers 100 times thinner than human hair for potential applications in batteries for electric cars and personal electronicsResearchers at the University of California, Riversides Bourns College of Engineering (http://www.engr.ucr.edu/) have developed a novel paper-like material for lithium-ion batteries. It has the potential to boost by several times the specific energy, or amount of energy that can be delivered per unit weight of the battery. This paper-like material is composed of sponge-like silicon nanofibers more than 100 times thinner than human hair. It could be used in batteries for electric vehicles and personal electronics. The findings were just published in a paper, Mihri Ozkan (http://www.ee.ucr.edu/%7Emihrilab/), a professor of electrical and computer engineering, Cengiz S. Ozkan (http://www.engr.ucr.edu/%7Ecengizlab/), a professor of mechanical engineering, and six of their graduate students: Zach Favors, Hamed Hosseini Bay, Zafer Mutlu, Kazi Ahmed, Robert Ionescu and Rachel Ye. The nanofibers were produced using a technique known as electrospinning, whereby 20,000 to 40,000 volts are applied between a rotating drum and a nozzle, which emits a solution composed mainly of tetraethyl orthosilicate (TEOS), a chemical compound frequently used in the semiconductor industry. The nanofibers are then exposed to magnesium vapor to produce the sponge-like silicon fiber structure. Conventionally produced lithium-ion battery anodes are made using copper foil coated with a mixture of graphite, a conductive additive, and a polymer binder. But, because the performance of graphite has been nearly tapped out, researchers are experimenting with other materials, such as silicon, which has a specific capacity, or electrical charge per unit weight of the battery, nearly 10 times higher than graphite. The problem with silicon is that is suffers from significant volume expansion, which can quickly degrade the battery. The silicon nanofiber structure created in the Ozkans labs circumvents this issue and allows the battery to be cycled hundreds of times without significant degradation. Eliminating the need for metal current collectors and inactive polymer binders while switching to an energy dense material such as silicon will significantly boost the range capabilities of electric vehicles, Favors said. This technology also solves a problem that has plagued free-standing, or binderless, electrodes for years: scalability. Free-standing materials grown using chemical vapor deposition, such as carbon nanotubes or silicon nanowires, can only be produced in very small quantities (micrograms). However, Favors was able to produce several grams of silicon nanofibers at a time even at the lab scale. The researchers future work involves implementing the silicon nanofibers into a pouch cell format lithium-ion battery, which is a larger scale battery format that can be used in EVs and portable electronics.Source: UCR Today (http://ucrtoday.ucr.edu/27263)
Researchers from UPM have developed a manufacturing method of aluminum optical nanosensors on versatile substrates that can be used for wearable devices and smart labels. A new method developed at the Institute of Optoelectronics Systems and Microtechnology (http://www.isom.upm.es/eng/index.php) (ISOM) from the Universidad Politécnica de Madrid (http://www.upm.es/internacional) (UPM) will enable the fabrication of optical nanosensors capable of sticking on uneven surfaces and biological surfaces like human skin. This result can boost the use of wearable devices to monitor parameters such as temperature, breath and heart pressure. Besides, it is a low cost technology since they use materials like standard polycarbonate compact disks, aluminum films and adhesive tapes that would facilitate its implementation on the market.Researchers from Semiconductor Devices Group (http://www.upm.es/observatorio/vi/index.jsp?pageac=grupo.jsp idGrupo=260) of ISOM from UPM have not only designed a manufacturing method of optical nanosensors over a regular adhesive tape but also have shown their potential applications. These flexible nanosensors enable us to measure refractive index variations of the surrounding medium and this can be used to detect chemical substances. Besides, they display iridescent colors that can vary according to the viewing and illumination angle, this property facilitates the detection of position variations and surface topography to where they are stuck at a glance. Nanosensors consist of dimensional nanohole arrays (250 nm) which are drilled into an aluminum layer (100 nm thick). In order to cause sensitivity to the surrounding mediums and iridescence effects, these nanostructures confine and disperse light according to the will of the engineer who designs them. The creation method for flexible nanosensors consists, firstly, on manufacturing sensors over a compact disc (CDs) of traditional polycarbonate, and secondly, transferring these sensors to adhesive Scotch tapes by a simple stick-and-peel procedure. This way, the nanosensors go from the CD surface to the adhesive tape (flexible substrate). The stick-and-peel process can be watched at: http://1drv.ms/1Jgf6Hd (http://1drv.ms/1Jgf6Hd) This new technology uses low cost materials such as polycarbonate CDs, aluminum, and regular adhesive tapes. The usage of noble metals to develop these types of sensors is common, but it is difficult mass production due to the high cost. Aluminum is 25,000 times cheaper than gold and has excellent electrical and optical properties. Besides, CD surfaces provide adherence to aluminum that is strong enough to manufacture the sensors over the CDs and weak enough to be transferred to the adhesive tape. This research is led by Dr. Carlos Angulos Barrios, a researcher from ISOM and Professor at the Department of Photonics Technology and Bioengineering (http://www.tfo.upm.es/) (TFB) of the School of Telecommunications Engineering (http://www.etsit.upm.es/index.php/en/), and also led by Víctor Canalejas Tejero, a PhD student of ISOM. The results were published in the Nanoscale journal ("Compact discs as versatile cost-effective substratesfor releasable nanopatterned aluminium films" (http://pubs.rsc.org/en/Content/ArticleLanding/2015/NR/C4NR06271J#!divAbstract) ).Source: Universidad Politécnica de Madrid (http://www.upm.es/internacional/UPM/UPM_Channel/News/03db4bb9a70cb410VgnVCM10000009c7648aRCRD)
NanoBCA was fortunate to engage in a conversation with Dr. Michael A. Meador, the recently appointed Director of the National Nanotechnology Coordination Office (NNCO) on February 10, 2015. Dr. Meador, who is technically on loan from NASA to NNCO for this assignment, has a Ph.D. in Chemistry from Michigan State University where he began his career thinking about matter at the molecular scale. While at NASA, Dr. Meadors efforts included development of game-changing technologies from the TRL 4 to TRL 6 levels with a focus on specific technologies such as carbon nanotube based structural composites, nano-based sensors for chemical and biotech detection, among others. The following excerpt, from the NNCO website, outlines Dr. Meadors impressive credentials and background with regard to nanotechnology. Dr. Meador, chair of NASAs Nanotechnology Roadmap Team, was instrumental in developing the NASA-wide Nanotechnology Project, and has been responsible for project planning and advocacy, overseeing technical progress, developing external partnerships to advance and transfer technology, coordinating with other nanotechnology related activities within NASA, and interacting with program and senior agency management. He has also played a key role in representing NASA in the NNIs interagency activities, including co-chairing its Nanomanufacturing, Industry Liaison, and Innovation Working Group. During his long career at NASA, Dr. Meador has held a series of positions with increasing responsibility, including over twenty years as Chief of the Polymers Branch of the Materials Division at NASA Glenn Research Center, where he expanded the research portfolio of the branch from research in high-temperature stable polymers and composites for aircraft engines to include work in battery electrolytes, fuel cell membranes, and nonlinear optical and sensor materials. He also initiated the first nanotechnology program at NASA Glenn. Dr. Meador has been recognized as the NASA Glenn Small Disadvantaged Business Program Technical Advocate of the Year and NASA Small Business Program Technical Personnel of the Year. He has also received the NASA Equal Opportunity Employment Medal for his work to increase the involvement of faculty and students from minority serving institutions in NASA materials research, and last month was awarded the NASA Exceptional Service Medal for leading NASA's Nanotechnology R D activities and representing the agency as a proactive member of the NNI. NanoBCA How long have you been a devotee of the science of nanotechnology? Dr. Meador Dating back to my graduate studies, I have long been aware of the great potential of working with matter at the molecular level. I carried this interest with me to NASA where, as Chief of the Polymers Branch at the Glenn Research Center, I launched one of the first research efforts with NASA focused on the development of nanomaterials technologies. Around 1999 or so, NASA started a long-term relationship with Dr. Richard Smalley of Rice University to focus on scaling up his HiPCO process to produce single wall carbon nanotubes so that we could have a sufficient quantity to evaluate as an additive for polymers. We were fortunate to be a part of that activity. The scale up approach developed under this activity led to Carbon Nanotechnologies Inc. So, I guess you can say that I have been involved with the science of nanotechnology for over 30 years. NanoBCA From a career perspective, what led you to become the Director at NNCO? Dr. Meador Over the course of my career, I have been involved in all aspects of nanotech research and development at a variety of levels within NASA from managing activities in my branch to more recently managing a NASA-wide project in nanotechnology. For the past four years I also served as NASAs principal representative to the NSET, which gave me a broader perspective on nanotech R D at the Federal government level. It seemed like a very natural progression to aspire to a position like this at NNCO where I could give back, in a leadership role, and utilize my unique career experience with regards to nanotechnology. Personally, it is very exciting for me to be in a position to help push the NNI forward, especially now that it is at a crossroads in that it is coming out of a research and development focused effort to a more defined commercialization effort. NanoBCA The 21st Century Nanotechnology Research and Development Act was signed into law on December 3, 2003. What do you see as the major successes of this Act and what needs to be done going forward? Dr. Meador If not for National Nanotechnology Initiative (NNI), which preceded and was then reauthorized by the 21st Century Nanotechnology Research and Development Act, certain industries would not have been created, or at a minimum, would have been created at a much later date. That alone is a very significant accomplishment of the NNI. For instance, the quantum dot industry would not be where it is today if not for the NNI. As you know, Sony announced a new TV recently at the Consumer Electronics Show that will incorporate quantum dots produced by QD Vision, Inc. to enhance picture quality. QD Vision won the 2014 Presidential Green Chemistry Challenge Award (http://www2.epa.gov/green-chemistry/presidential-green-chemistry-challenge-winners) from the U.S. Environmental Protection Agency, which is the highest domestic honor in the field, recognizing chemical technologies that incorporate the principles of green chemistry into chemical design, manufacture, and use. So, it is clear that the quantum dot industry is making an important impact on our economy, and our environment, and it is an industry that is here to stay. Another example is the carbon nanotube sector, with companies like Nanocomp Technologies, Inc. that are producing materials that not only reduce weight but also greatly improve strength in all sorts of products. Moving forward, we are honing our focus on supporting and expanding success stories like these, particularly as they relate to the commercialization of nanotechnologies. To that end, Dr. Lisa Friedersdorf, NNCO Deputy Director, and I have plans to visit all NSET agencies to talk about their agencys vision and the NNCOs vision and to try to establish a plan to more effectively work together to achieve the collective goals of the NNI. We recently visited the NIST Center for Nanoscale Science and Technology, which is truly a world-class facility. This is yet another example of the success of the 21st Century Nanotechnology Research and Development Act and reflects the tangible return on investment from that piece of legislation. So, I think there are a number of examples where nanotechnologies have definitely established a presence in the marketplace, but there is much more that we can do to facilitate the commercialization of nanotechnologies. NanoBCA What is your plan to further impact commercialization? Dr. Meador Success will come from good communications and a focused effort to have NNI agencies work directly with industry to identify and address any roadblocks to commercialization. To that end, the NNCO has initiated a webinar series to highlight problems that industry is facing with regards to nanotech commercialization. This has proven to be a great communications vehicle to provide information, especially to small- and medium- sized business, on topics like insurance and regulations that could help them be more successful in their commercialization efforts. These webinars are scheduled to occur once every other month and are designed to be easily accessible to the broadest audience. NanoBCA One of the challenges that we see regularly at the NanoBCA, is to address the question of whether or not the over $20 billion, that was invested by the 21st Century Nanotechnology Research and Development Act, was worthwhile from a taxpayers perspective. Is this a question with which you are confronted? Dr. Meador Yes, this is a very important question that needs to be addressed loudly and clearly and provide a compelling justification for the past and continued investment in the NNI. Fortunately, I have benefitted from sitting on NSET through the critical years and have had a front row seat to witness the impact of this investment. As I mentioned before, there are tangible examples of the return on investment that can be seen in the establishment of new industries and new products which also, not insignificantly, mean new jobs. Also, there has been the establishment of critical new infrastructure, like the NIST Center for Nanoscale Science and Technology. However, it is critically important that the news of these returns be communicated clearly to all stakeholders, which includes the taxpayer, the media and the broader community beyond just those in industry and government who happen to be concerned with nanotechnology as a part of their daily function. That is the challenge that faces us today at NNCO. To address that challenge and to do a better job of communication, NNCO is taking action on several fronts, some of which are quite simple yet very effective. I have already mentioned our webinar series. We are also developing our YouTube channel and reaching out to stakeholders in government and industry to contribute video content that highlights their work. Our goal is to create a buzz about the great potential of nanotechnology commercialization. We are also reaching out directly to students and have established several contests that they can participate in to highlight their research projects (and even art projects). The winners of these contests will be duly recognized at national events. Which brings me to my final point on this matter, which is that we are expanding and improving the quality of our events across the board with the intent of improving the overall impact of our communications. NanoBCA Have you noticed, as we have at NanoBCA, that critics often have misconstrued the literal mandate of the 21st Century Nanotechnology Research and Development Act and perhaps not appreciated that the investment was designed to be on infrastructure and R D, as the name of the Act itself suggests? Dr. Meador Since the inception of the NNI, participating agencies within the Federal government have invested over $20B in nanotechnology related R D. So, I think it is a fair question to ask what the impact of that investment has been on the US economy and job creation. In fact, the Presidents Council of Advisors on Science and Technology (PCAST) in its last two reviews, and the National Research Council (NRC), in its last review, have both called for a clear set of metrics to measure the success of the NNI. We are carefully considering how to develop these metrics by utilizing reports, such as the series of reports over the years by firms such as Lux Research on total revenues generated by nanotech products, as well as other studies which measure the impact of emerging technologies in other ways. Some of the inputs are not just on revenue data, but also on foundational impact such as the establishment of new technologies, sectors and even industries. The bottom line is that we all need to work together to create a better understanding, among the broadest audience possible, of the true impact of nanotechnologies on our society.
While carbon nanotubes (CNTs) have long attracted interest for nanoscale electronics, practical deployment of the technology requires a level of device consistency that is still a long way from being achieved. Now researchers at IBM in the US have identified the main source of device variability in CNT transistors and ways of reducing it. In recent years, silicon transistors have been fast approaching their minimum size. Short channel effects and increasing chip power density may halt the trend in constantly decreasing transistor sizes described in 'Moores Law'. Fortunately, there is an alternative. "The goal of our research is to develop carbon nanotube transistors into a practical technology that can replace silicon in future generations of high-performance microprocessor chips," says Qing Cao (http://researcher.ibm.com/researcher/view.php?person=us-qcao), who led the IBM research team behind these latest results. Carbon nanotubes have excellent short channel control, a low resistivity between the CNTs and metal contacts, and transport behaviour that allows much lower power consumption for the same on-current density. However where they have fallen short so far is in the uniformity between CNT devices. "Ultimately we want to integrate billions of nanotube transistors into functional circuits," says Cao. "To do this, we need good consistency from one transistor to the next, so they can all work together at the same voltage." Their latest study demonstrates that the device variability does not originate from the nanotubes themselves, and that it may be reduced by improved deposition processes and better materials for the dielectric components.Finding the root of the problem The researchers fabricated hundreds of bottom-gated field-effect transistors, each made from a p-channel single-walled CNT with a 10nm HfO2 layer deposited as the gate dielectric. Systematic experiments with the devices identified the amount of variability from device to device. The measurements also confirmed that variation in carbon nanotube diameter was not a dominant source of variability in device performance. The IBM team then built pairs of devices, where the same nanotube was used as the channel for both transistors. Observations of the performance of device pairs revealed that the dominant source was random, and so likely material-related rather than a systematic process-related contribution. Further analysis indicated that trapped charges fixed at the oxide/air interface were the prime suspect. "I think the results show that it is possible to build practical circuits based on nanotube transistors, but we still need to reduce the variability by several-fold," Cao tells nanotechweb.org. "We have identified the major source as the oxide surface, not anything intrinsic to the nanotubes, so we think we can make it happen with a better fabrication process." He suggests that the variability may be reduced by better control over the nanotube source and the deposition process. "The current nanotube solution isnt really electronic grade, so we may introduce charges on the oxide during the nanotube deposition process," says Cao. He also suggests that using high quality dielectrics with no free surface near the nanotube may also help. From working to working well Cao describes how far CNT electronics has come in the past few decades. "In the beginning, it was an achievement just to make a few good transistors," he says. The fabrication techniques for these devices are now so advanced that it is possible to fabricate a large enough number of high-quality semiconducting nanotubes to study their random behaviour. He adds, "As it gets closer to becoming a practical technology, the device variability becomes an increasingly important issue." Next the team will work to try and find where the trapped charges come from, and whether they are mainly from dangling bonds at the oxide surface, damage to the oxide during the fabrication process, or residue left by the nanotube solution do that they can eliminate them. Full details are reported in nanotechweb.org (http://nanotechweb.org/cws/article/tech/60243)
A recent agreement between The University of Texas at Dallas and Lintec of America is expected to propel scientific discoveries from the Universitys laboratories into the global marketplace and create jobs in North Texas. UT Dallas Office of Technology Commercialization (http://www.utdallas.edu/research/otc/) has licensed to Lintec of America a process developed over several years by Dr. Ray Baughman (http://www.utdallas.edu/chairs/profiles/baughman.html), the Robert A. Welch Distinguished Chair in Chemistry, and his colleagues at the Universitys Alan G. MacDiarmid NanoTech Institute (http://nanotech.utdallas.edu/about/index.html), which he directs. The patented process transforms tiny tubes of carbon 10,000 times thinner than the width of a human hair into useful large-scale structures, such as sheets and yarns, that are super-strong and extremely light. The carbon nanotube materials have unique thermal, mechanical and electrical properties, making them potentially suitable for use in areas such as wearable electronics, electronic displays, solar panels, sound projectors, batteries and harvesters of waste energy. Lintec of America is a subsidiary of Japan-based Lintec Corporation (http://www.lintec-global.com/), a leading manufacturer of pressure-sensitive adhesives. The companys advanced materials and industrial products are used in items ranging from electronic devices and computer displays to building and automotive materials. Lintec recently opened the Nano-Science Technology Center (http://lintec-nstc.com/) in Richardson. Less than 5 miles from the UT Dallas campus, it is devoted specifically to the manufacture and commercialization of the carbon nanotube structures. Dr. David E. Daniel, president of UT Dallas, said the whole process from lab to marketplace exemplifies how research universities impact the economy and society. One of the important roles a research university plays in the community is to translate the creativity and human talent developed on campus into the private sector, he said. This agreement is an example of UT Dallas doing exactly what it should be doing fostering an ecosystem of hugely creative faculty who educate and train exceptional students, who then contribute significantly to business and add value to society. Additionally, two UT Dallas alumni are leading efforts at the Nano-Science Technology Center: Dr. Kanzan Inoue MS01 PhD05 is managing director of the facility, and his wife, Dr. Raquel Ovalle-Robles MS06 PhD08, is the chief research and intellectual properties strategist. Both worked in the NanoTech Institute with Baughman and Dr. Anvar Zakhidov (http://nanotech.utdallas.edu/personnel/staff/zakhidov.html), professor of physics. Inoue said proximity to the University and access to its intellectual resources were primary factors in locating the new facility in Richardson. The Nano-Science Technology Center was created to bridge the gaps between laboratory research, pilot production and ultimately full production processes, he said. Individual carbon nanotubes (CNTs) are much lighter, stronger and more thermally conducting than metals or diamond. However, applying CNTs in practical applications requires scalable and controllable processing methods for assembling them into products without losing the unique properties of individual CNTs.Inoue also said that a critical factor for the controllable device fabrication is the ability to assemble CNTs in different forms, such as free-standing or on a substrate.The technology developed at UT Dallas delivers an efficient and elegant solution to these key issues, he said. The electrically conducting CNT sheets that we can now make are lighter than air, transparent and much stronger per pound than steel. Lintec has been an industrial affiliate of the NanoTech Institute for many years, and Baughman said the pairing of the UT Dallas science and technology with the companys manufacturing capabilities was a natural match. Lintec has expertise in technologies that will be critically important for economically manufacturing carbon nanotube sheets and converting these sheets into a wide range of products, said Baughman, a National Academy of Engineering member who joined the UT Dallas faculty in 2001 after a 30-year career in private industry. They invested in UT Dallas technology because they saw potential for valuable end products and because their manufacturing capabilities are particularly well-suited for upscaling the production of these materials to industrial levels. Baughman said the licensing agreement will enable teaming that eliminates barriers between scientific and technological breakthroughs and products, which is an important goal of the NanoTech Institute. Im very happy that Lintec decided to open its new facility in Richardson in order to be close to and work collaboratively with our NanoTech Institute, and that they are creating jobs in Texas, he said. Im also delighted that the leaders of this new business venture are UT Dallas alumni from our institute. I know how brilliant they are and look forward to their accomplishments. Source: The University of Texas at Dallas (http://www.utdallas.edu/news/2015/2/9-31409_Nanotech-Discoveries-Move-from-Lab-to-Marketplace-_story-wide.html?WT.mc_id=NewsHomepageFeature)
Entry Planned Into $50 Billion Global Cleaning MarketIn direct response to the apparent failure of current cleaners and disinfectants to prevent the spread of illness, PEN Inc. (OTCQB: PENC) is developing a new category of cleaning products intended to clean and fortify surfaces at the nanoscale-level. Unlike traditional harsh pesticide-containing disinfectants, PEN products will incorporate natural elements and sustainable chemistry to keep surfaces safe. The company's aim is to revolutionize the $50 billion global market for industrial and institutional cleaning, which includes lodging, retail outlets, and workplaces. The product is also ideal for the $80 billion global household cleaning market."The news is filled with stories of people being sickened on cruise ship vacations, amusement park visits, and at other public venues," noted Scott E. Rickert, PEN's Chairman, President and CEO. "This PEN product aims to redefine personal health and safety, so consumers can stop worrying about germs and disease every time they touch a restaurant table, airplane armrest, bank ATM machine, or hotel room door." Dr. Rickert added, "Just as important, the patent-pending product will use only safe, sustainable ingredients -- no pesticides or harsh chemicals. In fact the primary ingredient, as listed on the label, is a food additive." Dr. Rickert also addressed the market opportunity. "I expect PEN's first product to expand into a family of products to tackle the problem of safe, healthy surfaces, worldwide. My vision for PEN is to harness the vast potential of nanotechnology to create innovative, breakthrough products for a global marketplace. In PEN we have both the R D expertise and the commercialization experience to begin the process of bringing this product to market." About PEN Inc. (OTCQB: PENC)PEN Inc. (PENC) is a global leader in developing, commercializing and marketing enhanced-performance products enabled by nanotechnology. The company focuses on innovative and advanced product solutions in safety, health and sustainability. For more information about PEN Inc, visit www.pen-technology.com (http://www.pen-technology.com/). Source: PEN Inc. (http://my.mwnewsroom.com/pennewsroom/New-PEN-Inc-Surface-Cleaning-Product-to-Redefine-Personal-Health-and-Safety--11G032156-001)
The National Academy of Engineering report that was just released in 2014 on The Flexible Electronics Opportunity (http://www.nap.edu/catalog/18812/the-flexible-electronics-opportunity) has re-established interest in this growing area which includes strategic opportunities for several future technology platforms, including the Internet of Things, and wearable sensors and systems. The key recommendations are well aligned with strategies, goals and public-private partnerships that have been developing over the past decade. Key recommendations from the report are consistent with the challenges and opportunities that the relevant committees have determined, with the committee recommending the following: The United States should increase funding of basic research related to flexible electronics and augment support for university-based consortia to develop prototypes, manufacturing processes, and products in close collaboration with contributing industrial partners. Consortia, bringing together industry, universities, and various levels of government, should be used as a means of fostering precompetitive applied research in flexible electronics. The United States should establish and support a network of user facilities dedicated to flexible electronics. Where possible, federal efforts to support the growth of competitive flexible electronics industries should leverage state and regional developmental efforts, with the objective of establishing co-located local supply chains and capturing the associated cluster synergies.Agency mission needs should help drive demand for flexible electronics technologies, while lowering costs, improving capabilities, and contributing to the development of a skilled workforce. These recommendations build upon the developments by numerous institutions in establishing industry consortia user facilities to transition the innovations in materials, processes, and integration to industrially meaningful platforms. As such, innovations in nanomaterials and nanomanufacturing processes emerging from NSF Nanoscale Science and Engineering Centers (NSECS) and Nanosystems Engineering Research Centers (NERCs) will play a pivotal role in the innovation cycle to accelerate developments in flexible-hybrid electronics technologies and manufacturing platforms. Complimenting this are the manufacturing demonstration facilities that have been established at various universities as industry user facilities to take advantage of these emerging processes and cutting edge tools that are unavailable elsewhere. Examples include the Center for Advanced Microelectronics Manufacturing (CAMM) at Binghamton University, the Flexible Display Center at Arizona State University, and the Center for Advanced Roll-to-Roll Manufacturing at the University of Massachusetts Amherst. The examples of academic driven public-private partnerships provide leading edge capabilities accessible to industry for acceleration of innovative product development.
New battery technology from the University of Michigan should be able to prevent the kind of fires that grounded Boeing 787 Dreamliners in 2013. The innovation is an advanced barrier between the electrodes in a lithium-ion battery. Made with nanofibers extracted from Kevlar, the tough material in bulletproof vests, the barrier stifles the growth of metal tendrils that can become unwanted pathways for electrical current. A U-M team of researchers also founded Ann Arbor-based Elegus Technologies to bring this research from the lab to market. Mass production is expected to begin in the fourth quarter 2016. "Unlike other ultra strong materials such as carbon nanotubes, Kevlar is an insulator," said Nicholas Kotov, the Joseph B. and Florence V. Cejka Professor of Engineering. "This property is perfect for separators that need to prevent shorting between two electrodes."Lithium-ion batteries work by shuttling lithium ions from one electrode to the other. This creates a charge imbalance, and since electrons can't go through the membrane between the electrodes, they go through a circuit instead and do something useful on the way. But if the holes in the membrane are too big, the lithium atoms can build themselves into fern-like structures, called dendrites, which eventually poke through the membrane. If they reach the other electrode, the electrons have a path within the battery, shorting out the circuit. This is how the battery fires on the Boeing 787 are thought to have started. "The fern shape is particularly difficult to stop because of its nanoscale tip," said Siu On Tung, a graduate student in Kotov's lab, as well as chief technology officer at Elegus. "It was very important that the fibers formed smaller pores than the tip size." While the widths of pores in other membranes are a few hundred nanometers, or a few hundred-thousandths of a centimeter, the pores in the membrane developed at U-M are 15-to-20 nanometers across. They are large enough to let individual lithium ions pass, but small enough to block the 20-to-50-nanometer tips of the fern-structures. The researchers made the membrane by layering the fibers on top of each other in thin sheets. This method keeps the chain-like molecules in the plastic stretched out, which is important for good lithium-ion conductivity between the electrodes, Tung said. "The special feature of this material is we can make it very thin, so we can get more energy into the same battery cell size, or we can shrink the cell size," said Dan VanderLey, an engineer who helped found Elegus through U-M's Master of Entrepreneurship program. "We've seen a lot of interest from people looking to make thinner products." Thirty companies have requested samples of the material. Kevlar's heat resistance could also lead to safer batteries as the membrane stands a better chance of surviving a fire than most membranes currently in use. While the team is satisfied with the membrane's ability to block the lithium dendrites, they are currently looking for ways to improve the flow of loose lithium ions so that batteries can charge and release their energy more quickly. The study, "A dendrite-suppressing solid ion conductor from aramid nanofibers," (http://www.nature.com/ncomms/2015/150127/ncomms7152/full/ncomms7152.html) appeared online Jan. 27 in Nature Communications. Source: University of Michigan (http://ns.umich.edu/new/multimedia/slideshows/22645-bulletproof-battery-kevlar-membrane-for-safer-thinner-lithium-rechargeables)
The coming age of wearable, highly flexible and transparent electronic devices will rely on essentially invisible electronic and optoelectronic circuits. In order to have close to invisible circuitry, one must have optically transparent thin-film transistors (TFTs). In order to have flexibility, one needs bendable substrates. Both flexible electronics and transparent electronics have been demonstrated before, but never rollable electronics that are also fully transparent at the same time. This has now been achieved by a team of researchers in Korea, who have successfully built rollable and transparent electronic devices that are not only lightweight, but also don't break easily. To manufacture flexible electronics, one needs a starting material the substrate on which to build-up the device. In order for the final product to be flexible, the substrate of course also has to be flexible. In fact, it is the substrate that determines, to a large extent, the overall flexibility of the final product. So if the substrate is flexible to an extent of being rollable which can be achieved making it very thin the final product will also, to some extent, be rollable. Of course, the semiconductors, dielectrics, and metals making up the electronic device, should also be similarly flexible (or soft), otherwise faults will occur. Plastics are the obvious choice for flexible substrates as the substrates are also required to be insulating (nonconductive) in most applications. Other obvious advantages of plastics are that they are lightweight and non-breakable. A team led by Professor Jin Jang, Director of the Department of Information Display (http://display.khu.ac.kr/) at Kyung Hee University, has achieved this by overcoming two major challenges associated with the manufacture of flexible electronics: The temperature restriction of plastic substrates (<100°C) and the difficulty of handling flexible electronics during the fabrication process. They reported their findings in ACS Applied Materials Interfaces ("Fully Transparent and Rollable Electronics" (http://dx.doi.org/doi:10.1021/am506937s)). "To overcome the temperature restriction we chose our plastic substrate to be polyimide (PI), which is a polymer of imide monomers," Jang explains to Nanowerk. "PI has high chemical and heat resistance and when it is colorless, which is the case of this research, it withstands processing temperatures around 300°C." The researchers also chose an amorphous oxide semiconductor amorphous-indium-gallium-zinc-oxide (a-IGZO) which assures good device performance even when sputter-deposited at low temperatures. For consistency, they also chose a zinc-based metal, indium-zinc-oxide (IZO), for the metal electrodes i.e. the gate, source, and drain electrodes of the field-effect transistors making up the electronic devices. "Both the a-IGZO and IZO have large band-gaps, and therefore, are transparent to visible light," says Jang. "As the dielectrics are also transparent and the substrate (PI) is colorless, the final product is see-through with a transmittance of 70% for the full circuit device. The colorless PI (CPI) is 15 µm thick and the thickness of the electronic devices is ∼1 µm, resulting in a total thickness of the fabricated thin-film transistor of only ∼16 µm. Hence, the electronic devices are rollable." In order to deal with the second major challenge the difficulty of handling flexible electronics during the fabrication process the researchers used a carrier glass substrate on which the CPI is first spin-coated from solution, and then detached from after device fabrication. Being around 0.7 mm in thickness, the carrier glass is rigid enough to provide mechanical support for the CPI, without which accurate layer registration is impossible during photolithography. This is because standalone plastics substrates can warp, shrink, or bulge at high temperatures. "A rigid carrier substrate is, therefore, a necessity when vacuum processes and photolithography are involved," Jang notes. "However, the way the flexible substrate is attached to the rigid carrier substrate is important as it has to be detached from the carrier substrate after device fabrication. The use of adhesive materials/glues to attach flexible substrates to carrier substrates is not recommended as most adhesives cannot withstand high processing temperatures." An alternative method is to spin-coat the flexible substrate from solution onto the carrier substrate. Although this method avoids the use of adhesive materials, it is very difficult to detach the flexible substrate from the carrier substrate afterwards because bonds between the two have a tendency of strengthening during the fabrication process. "The current solution is to deposit a thin layer such as amorphous-silicon between the flexible substrate and the carrier substrate, which can be evaporated by a laser to release the flexible substrate from the carrier substrate after device fabrication," says Jang. "Given the high cost of installing laser equipment, the complexity of the laser detachment process, and the limitations of the laser beam size, we felt their was a need for a better method." In their research, Jang's team do not use adhesive material or lasers. Neither do they deposit a layer of amorphous-silicon between the carrier glass and the CPI. Instead, they spin coat a mixture of carbon nanotubes (CNT) and graphene oxide (GO) to a thickness of 1 nm from solution onto of the carrier glass before spin coating the CPI. "As the CNT/GO layer has a flake like structure with CNT links, it decreases the area where the CPI contacts the glass, thereby reducing its adhesion to glass," explains Jang. "Inserting the CNT/GO layer also doesn't cost much because only a few drops are required to achieve a thickness around 1 nm." After fabrication, only a small amount of mechanical force is required to detach the CPI from the glass. According to the scientists, the beauty of having the CNT/GO layer is that it bonds stronger with the CPI compared to the glass, such that it remains embedded to the backside of the CPI after detachment providing mechanical support to the flexible electronics and making the rollable electronics wrinkle-free. Electronic devices built on plastic substrates are prone to electrostatic discharge (ESD) damage because plastics are usually associated with the generation of electrostatic charge. By contrast, the CPI in this present work is ESD-free because localized ESD can be released via the conductive CNT. In their experiments, the team rolled the TFT devices 100 times on a cylinder with radius of 4 mm, without significantly degrading their performance. Integrated circuits also operated without degradation, while being bent to a radius of 2 mm, making these devices suitable for transparent and rollable displays. Source: Nanowerk (http://www.nanowerk.com/spotlight/spotid=38815.php)
To stay warm when temperatures drop outside, we heat our indoor spaces even when no one is in them. But scientists have now developed a novel nanowire coating for clothes that can both generate heat and trap the heat from our bodies better than regular clothes. They report on their technology, which could help us reduce our reliance on conventional energy sources, in the ACS journal Nano Letters ("Personal Thermal Management by Metallic Nanowire-Coated Textile" (http://dx.doi.org/doi:10.1021/nl5036572)). Yi Cui and colleagues note that nearly half of global energy consumption goes toward heating buildings and homes. But this comfort comes with a considerable environmental cost it's responsible for up to a third of the world's total greenhouse gas emissions. Scientists and policymakers have tried to reduce the impact of indoor heating by improving insulation and construction materials to keep fuel-generated warmth inside. Cui's team wanted to take a different approach and focus on people rather than spaces. The researchers developed lightweight, breathable mesh materials that are flexible enough to coat normal clothes. When compared to regular clothing material, the special nanowire cloth trapped body heat far more effectively. Because the coatings are made out of conductive materials, they can also be actively warmed with an electricity source to further crank up the heat. The researchers calculated that their thermal textiles could save about 1,000 kilowatt hours per person every year that's about how much electricity an average U.S. home consumes in one month. Source: American Chemical Society (http://www.acs.org/content/acs/en/pressroom/presspacs/2015/acs-presspac-january-28-2015/nanowire-clothing-could-keep-people-warm-without-heating-everything-else.html)
Researchers from North Carolina State University have developed a new, wearable sensor that uses silver nanowires to monitor electrophysiological signals, such as electrocardiography (EKG) or electromyography (EMG). The new sensor is as accurate as the wet electrode sensors used in hospitals, but can be used for long-term monitoring and is more accurate than existing sensors when a patient is moving. Long-term monitoring of electrophysiological signals can be used to track patient health or assist in medical research, and may also be used in the development of new powered prosthetics that respond to a patients muscular signals. Electrophysiological sensors used in hospitals, such as EKGs, use wet electrodes that rely on an electrolytic gel between the sensor and the patients skin to improve the sensors ability to pick up the bodys electrical signals. However, this technology poses problems for long-term monitoring, because the gel dries up irritating the patients skin and making the sensor less accurate. The new nanowire sensor is comparable to the wet sensors in terms of signal quality, but is a dry electrode it doesnt use a gel layer, so doesnt pose the same problems that wet sensors do. People have developed other dry electrodes in the past few years, and some have demonstrated the potential to rival the wet electrodes, but our new electrode has better signal quality than most if not all of the existing dry electrodes. It is more accurate, says Dr. Yong Zhu, an associate professor of mechanical and aerospace engineering at NC State and senior author of a paper describing the work. In addition, our electrode is mechanically robust, because the nanowires are inlaid in the polymer. The sensors stem from Zhus earlier work to create highly conductive and elastic conductors (https://news.ncsu.edu/2012/07/wms-zhu-silver-stretch/) made from silver nanowires, and consist of one layer of nanowires in a stretchable polymer. The new sensor is also more accurate than existing technologies at monitoring electrophysiological signals when a patient is in motion. The silver nanowire sensors conform to a patients skin, creating close contact, Zhu says. And, because the nanowires are so flexible, the sensor maintains that close contact even when the patient moves. The nanowires are also highly conductive, which is key to the high signal quality. The new sensors are also compatible with standard EKG- and EMG-reading devices. I think these sensors are essentially ready for use, Zhu says The raw materials of the sensor are comparable in cost to existing wet sensors, but we are still exploring ways of improving the manufacturing process to reduce the overall cost. An uncorrected proof of the paper, Wearable Silver Nanowire Dry Electrodes for Electrophysiological Sensing (http://pubs.rsc.org/en/content/articlelanding/2015/ra/c4ra15101a#%21divAbstract), was published online Jan. 14 in RSC Advances, immediately after acceptance. Lead author of the paper is Amanda Myers, a Ph.D. student at NC State. The paper was co-authored by Dr. Helen Huang, an associate professor in the joint biomedical engineering program at NC State and the University of North Carolina at Chapel Hill.Source: North Carolina State University
NanoSphere Health Sciences, LLC, innovative developers of the industry-first, patent-pending NanoSphere delivery system, announced today that the U.S. Patent and Trademark office issued "Patent Pending" status for its new NSAID NanoSphere technology platform. NanoSphere Health's NSAIDs are the first to encapsulate prescription and over-the-counter (OTC) NSAIDs (non-steroidal anti-inflammatory drugs such as Ibuprofen, Aspirin, Naproxen, etc.) as a method to treat and prevent inflammatory disorders and global inflammation and pain. The use of the NanoSphere delivery technology eliminates and alleviates many of the severe side effects NSAIDs can have, such as stomach irritation, stomach bleeding and GI bleeding, among others. At the same time, it increases the therapeutic activity of NSAIDs for safe, long-term and more effective therapy. NanoSphere NSAIDs are uniquely designed to be administered intraorally, intranasally and transdermally. The convenient liquid nanogels bypass the GI tract avoiding gastrointestinal irritation. When taken perorally, NanoSphere NSAIDs' structure of purified essential phospholipids maintains the protective GI tract mucosa barrier from damage by NSAIDs. The NanoSphere NSAIDs are then efficiently transported into the circulatory system for greater therapeutic activity in safely treating inflammatory conditions and relieving pain. "We are excited to announce that NanoSphere's NSAID technology platform has achieved a 'Patent Pending' status, protecting the intellectual property of our NanoSphere delivery system within NSAIDs," said Dr. Richard Kaufman, Chief Science Officer at NanoSphere Health Sciences. "Our disruptive NanoSphere delivery biotechnology introduces a significant advancement in the therapeutic potential and safety of OTC and prescription NSAIDs along with a tremendous growth potential." NSAIDs cause a range of gastrointestinal problems from mild upset stomach to serious conditions such as stomach bleeding, ulcers and kidney damage, factors which often limit their use. Among patients using NSAIDs, 30-40% have some degree of GI intolerance. NSAIDs physically damage the protective GI mucosa surface and promote bleeding. Furthermore, NSAIDs are fat-soluble drugs with low solubility and dissolution in water. This makes OTC and prescription NSAID pills hard to absorb and contributes to their causing GI problems. "The problems with current NSAID therapy are glaringly apparent," says Terry Grossman M.D., Medical Director at NanoSphere Health Sciences. "NSAIDs have low bioavailability and limited delivery into inflamed areas. They produce adverse effects, compounded with the fact that nearly half the population has difficulties swallowing currently sold NSAID pills and capsules." The company's patent-pending phospholipid nanoparticle encapsulation of NSAIDs technology provides the following potential benefits: Higher Concentration of NSAIDs Increased Bioavailability of NSAIDs (2-fold to 10-fold) Decreased Dosage of NSAIDS (2-fold to 10-fold) Enables Safe, Long-Term Use and More Efficacious NSAID Therapy and Treatment Reduced Risk of Gastrointestinal Problems Transport into and Targeting of Specific Body Sites Delivery into the Central Nervous System Enhanced Therapeutic Value Ideal for Long-Term and Daily Use NanoSphere Health expects availability of commercial licensing by the second quarter of 2015, after clinical trials have been completed. About NanoSphere Health Sciences, LLC With its headquarters in Denver, Colorado, NanoSphere Health Sciences is a biotechnology firm specializing in the creation of NanoSphere delivery systems for the supplement, nutraceutical, OTC and pharmaceutical industries. For more information, visit www.nanospherehealth.com (http://www.nanospherehealth.com) Source: NanoSphere Health Sciences
TechConnect World/Nanotech 2015 - Conference and ExpoJune14-17, 2015Washington, DC Final Call for Abstracts Innovations - Friday Jan. 16 Nanotech 2015/TechConnect World Innovation Conference June 14-17, 2015 - Washington DCFor an InterNano supporting partnership 10% discount on registration (http://www.techconnectworld.com/World2015/register.html) enter our code: INANO10 Abstract submission will close on Friday, January 16, for the TechConnect World Innovation Conference, June 14-17, Gaylord Convention Center, Washington DC, USA. On behalf of our symposium organizers we warmly invite you to submit your research abstract and participate in this exciting international event. How to Participate: Submit Your Abstract - due January 16th Submit your technical research and development innovations for review and consideration for podium or poster presentation. Submit Your Innovation - due January 30th We are looking for breakthrough technologies that are ready for licensing, corporate partnering, or investment opportunities. Innovators and Prospectors Include: All U.S. Funding AgenciesAll U.S. National Labs Top-tier Academic Innovators State Country Innovation Delegations Global Corporate Innovation Prospectors For further information, please visit: http://www.techconnectworld.com/World2015/ (http://www.techconnectworld.com/World2015/)Authors of research submissions, upon acceptance, registration (http://www.techconnectworld.com/World2015/register.html) enter our code: INANO10 About the event: The worlds largest nanotechnology event, Nanotech 2015, delivers application-focused research from the top international academic, government and private industry labs. Thousands of leading researchers, scientists, engineers and technology developers participate in Nanotech to identify new technology trends, development tools, product opportunities, R D collaborations, and commercialization partners. Join the global community that has been working together for over 17 years to integrate nanotechnology into industry with a focus on scale, safety and cost-effectiveness.The joint TechConnect World and the National Innovation Summit is uniquely designed to accelerate the commercialization of innovations, out of the lab and into industry. TechConnect World is divided into a Technical Research Program and an Innovation Partnering Program, gathering the world's leading market-focused research and commercially-viable innovations into the largest global technology accelerator program.
The IUMRS Global Leadership and Service Award for 2015 will be awarded to Dr. Mihail Roco, Mr. Christos Tokamanis, and Dr. Paul Siffert at a ceremony to be held at the European Parliament on Monday, 23rd February 2015 For 2015, the Award honors very distinguished individuals who have demonstrated outstanding leadership through services having measurable impact in the fields of Nanotechnology and materials for the global community: Professor Doctor Mihail Roco, the founding Chair of the National Science and Technology Council's subcommittee on Nanoscale Science, Engineering and Technology of USA National Science Foundation, for his extra-ordinary services in the area of Nanotechnology with significant impact in the USA and around the world. Mr. Christos Tokamanis, head of Unit "Advanced Materials and Nano Technologies" - Directorate "Key Enabling Technologies, Research Innovation", European Commission, for the outstanding services to the European Union community in supporting an effective and efficient nanotechnology policy integrating the needs of innovation with societal impact and responsible governance. Professor Doctor Paul Siffert, founder and First President of the "European Materials Research, Society" (E-MRS); General Secretary of the "European Materials Forum" (EMF) and of the "European Materials Research Society" (E-MRS), Czochralski Gold Medal, and for 30 years of dedicated services to European and Global Materials Community. The IUMRS has a mission of supporting excellence in materials research and education, and development of future leaders to work together for a world that has critical needs in order to sustain itself. Accordingly, to promote this mission, IUMRS announced the Global Leadership and Service Award. This Award will be given to individuals who have demonstrated outstanding leadership through service having measurable impact to the global community, relating to materials research and education. Source: IUMRS (http://www.iumrshq.org/attachments/197_Poster_Global_Awards_%281%29-final2-.pdf)
Webinar 1: Roadblocks to Success in Nanotechnology Commercialization What Keeps the Small and Medium Enterprise Community Up at Night? What: The NNCO will hold a series of webinars focusing on the experiences, successes, and challenges for small- and medium-sized businesses working in nanotechnology and on issues of interest to the business community. The first webinar is Roadblocks to Success in Nanotechnology Commercialization What Keeps the Small and Medium Enterprise Community Up at Night? When: The first webinar will be held Thursday, January 15, 2015, from 12:00 p.m. to 1:00 p.m. EST. This webinar will be a round-table discussion with small and medium-sized businesses involved in nanotechnology commercialization focused on understanding common problems that they face and identifying those problems that the NNCO and NSET can assist in overcoming. Who: Craig Bandes, Pixelligent LLC Doyle Edwards, Brewer Science Inc. Scott Rickert, PEN Inc. How: Questions of interest to the small- and medium-sized business community may be submitted to firstname.lastname@example.org (mailto:email@example.com) beginning one week prior to the event through the close of the webinar. During the question-and-answer segment of the webinars, submitted questions will be considered in the order received and may be posted on the NNI Web site (www.nano.gov (http://www.nano.gov/)). A moderator will identify relevant questions and pose them to the panelists. Due to time constraints, not all questions may be addressed during the webinar. The moderator reserves the right to group similar questions and to skip questions, as appropriate. Registration: Click here to register for this free, online event. (https://events-na12.adobeconnect.com/content/connect/c1/1305935587/en/events/event/shared/default_template/event_registration.html?sco-id=1309829163 _charset_=utf-8) Registration for the webinar is required and is on a first-come, first-served basis and will be capped at 200 participants. Source: NNCO (http://www.nano.gov/SMEwebinars2015)
Berkeley Lab Researchers Discovery of Piezoelectricty in Molybdenum Disulfide Holds Promise for Future MEMSA door has been opened to low-power off/on switches in micro-electro-mechanical systems (MEMS) and nanoelectronic devices, as well as ultrasensitive bio-sensors, with the first observation of piezoelectricity in a free standing two-dimensional semiconductor by a team of researchers with the U.S. Department of Energy (DOE)s Lawrence Berkeley National Laboratory (Berkeley Lab). Xiang Zhang, director of Berkeley Labs Materials Sciences Division and an international authority on nanoscale engineering, led a study in which piezoelectricity the conversion of mechanical energy into electricity or vice versa was demonstrated in a free standing single layer of molybdenum disulfide, a 2D semiconductor that is a potential successor to silicon for faster electronic devices in the future. Piezoelectricity is a well-known effect in bulk crystals, but this is the first quantitative measurement of the piezoelectric effect in a single layer of molecules that has intrinsic in-plane dipoles, Zhang says. The discovery of piezoelectricity at the molecular level not only is fundamentally interesting, but also could lead to tunable piezo-materials and devices for extremely small force generation and sensing.Zhang, who 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, is the corresponding author of a paper in Nature Nanotechnology describing this research. The paper is titled Observation of Piezoelectricity in Free-standing Monolayer MoS2. The co-lead authors are Hanyu Zhu and Yuan Wang, both members of Zhangs UC Berkeley research group. (See below for a complete list of co-authors.) Since its discovery in 1880, the piezoelectric effect has found wide application in bulk materials, including actuators, sensors and energy harvesters. There is rising interest in using nanoscale piezoelectric materials to provide the lowest possible power consumption for on/off switches in MEMS and other types of electronic computing systems. However, when material thickness approaches a single molecular layer, the large surface energy can cause piezoelectric structures to be thermodynamically unstable. Over the past couple of years, Zhang and his group have been carrying out detailed studies of molybdenum disulfide, a 2D semiconductor that features high electrical conductance comparable to that of graphene, but, unlike graphene, has natural energy band-gaps, which means its conductance can be switched off. Transition metal dichalcogenides such as molybdenum disulfide can retain their atomic structures down to the single layer limit without lattice reconstruction, even in ambient conditions, Zhang says. Recent calculations predicted the existence of piezoelectricity in these 2D crystals due to their broken inversion symmetry. To test this, we combined a laterally applied electric field with nano-indentation in an atomic force microscope for the measurement of piezoelectrically-generated membrane stress.Zhang and his group used a free-standing molybdenum disulfide single layer crystal to avoid any substrate effects, such as doping and parasitic charge, in their measurements of the intrinsic piezoelectricity. They recorded a piezoelectric coefficient of 2.9×10-10 C/m, which is comparable to many widely used materials such as zinc oxide and aluminum nitride. Knowing the piezoelectric coefficient is important for designing atomically thin devices and estimating their performance, says Nature paper co-lead author Zhu. The piezoelectric coefficient we found in molybdenum disulfide is sufficient for use in low-power logic switches and biological sensors that are sensitive to molecular mass limits. Zhang, Zhu and their co-authors also discovered that if several single layers of molybdenum disulfide crystal were stacked on top of one another, piezoelectricity was only present in the odd number of layers (1,3,5, etc.) This discovery is interesting from a physics perspective since no other material has shown similar layer-number sensitivity, Zhu says. The phenomenon might also prove useful for applications in which we want devices consisting of as few as possible material types, where some areas of the device need to be non-piezoelectric. In addition to logic switches and biological sensors, piezoelectricity in molybdenum disulfide crystals might also find use in the potential new route to quantum computing and ultrafast data-processing called valleytronics. In valleytronics, information is encoded in the spin and momentum of an electron moving through a crystal lattice as a wave with energy peaks and valleys. Some types of valleytronic devices depend on absolute crystal orientation, and piezoelectric anisotropy can be employed to determine this, says Nature paper co-lead author Wang. We are also investigating the possibility of using piezoelectricity to directly control valleytronic properties such as circular dichroism in molybdenum disulfide. In addition to Zhang, Zhu and Wang, other co-authors of the Nature paper were Jun Xiao, Ming Liu, Shaomin Xiong, Zi Jing Wong, Ziliang Ye, Yu Ye and Xiaobo Yin. This research was supported by Light-Material Interactions in Energy Conversion, an Energy Frontier Research Center (http://www.lmi.caltech.edu/) led by the California Institute of Technology, in which Berkeley Lab is a major partner. The Energy Frontier Research Center program is supported by DOEs Office of Science.Source: Lawrence Berkeley National Laboratory (http://newscenter.lbl.gov/2014/12/22/piezoelectricity-2d-semiconductor/)
UMass Amherst researchers invent fast, accurate new nanoparticle-based sensor system Traditional genomic, proteomic and other screening methods currently used to characterize drug mechanisms are time-consuming and require special equipment, but now researchers led by chemist Vincent Rotello at the University of Massachusetts Amherst offer a multi-channel sensor method using gold nanoparticles that can accurately profile various anti-cancer drugs and their mechanisms in minutes. As Rotello and his doctoral graduate student Le Ngoc, one of the lead authors, explain, to discover a new drug for any disease, researchers must screen billions of compounds, which can take months. One of the added keys to bringing a new drug to market, they add, is to identify how it works, its chemical mechanism. Rapid determination of drug mechanism would greatly streamline the drug discovery process, opening the pipeline of new therapeutics, Ngoc says. She adds, Drugs with different mechanisms cause changes in the surface of cells that can be read out using the new sensor system. We found that each drug mechanism generated a unique pattern, and we used these cell surface differences to quickly profile different drug mechanisms. Details of this work appear in the current issue of Nature Nanotechnology. To expedite drug screening, the research team, which in addition to the chemists includes a UMass Amherst cognitive scientist and a materials scientist from Imperial College, London, developed a new, signature-based approach using a gold nanoparticle sensor system and three differently labeled proteins by color: blue, green and red. Using an engineered nanoparticle and three fluorescent proteins provides a three-channel sensor that can be trained to detect subtle changes in cell surface properties, the authors note. Drug-induced cell surface changes trigger different sets of fluorescent proteins to turn on together, offering patterns that identify specific cell death mechanisms. The new nanosensor is generalizable to different cell types and does not require processing steps before analysis. So, it offers a simple, effective way to expedite research in drug discovery, toxicology and cell-based sensing, the researchers add. Some signature-based drug screening using traditional biomarkers exists today, but it requires multi-step cell processing and special equipment, limiting its usefulness the authors point out. With their three-channel, gold nanoparticle sensor platform, Rotello and colleagues solve those challenges and enhance accuracy. Further, they say, the information-rich output allows the determination of a chemotherapeutic mechanism from a single measurement, providing answers far more quickly (in minutes) than current methods, using standard laboratory instrumentation. This invention could have a substantial potential impact on the drug discovery pipeline, says Ngoc. The sensor is not only able to profile mechanisms for individual drugs but also determine the mechanisms of drug mixtures, that is, drug cocktails that are an emerging tool with many therapies, she adds. Rotello emphasizes, While we have decent knowledge of individual drugs, we still have a lot to learn about the mechanisms of combination therapies. In addition to drug screening, the simplicity and speed of this enabling technology holds the promise to greatly accelerate the search for effective cancer treatments, and provides a step forward in areas such as toxicology, where the safety of thousands of uncategorized chemicals needs to be assessed. The researchers point out that their new sensor system offers a potential way forward for toxicology, providing a viable method to classify the tens of thousands of commercial chemicals for which no data are available."Source: UMass Amherst (http://www.umass.edu/newsoffice/article/promising-new-method-found-rapidly)Image credit: Vincent Rotello, Department of Chemistry, University of Massachusetts-Amherst
New sensor can transmit information on hazardous chemicals or food spoilage to a smartphone.MIT chemists have devised a new way to wirelessly detect hazardous gases and environmental pollutants, using a simple sensor that can be read by a smartphone. These inexpensive sensors could be widely deployed, making it easier to monitor public spaces or detect food spoilage in warehouses. Using this system, the researchers have demonstrated that they can detect gaseous ammonia, hydrogen peroxide, and cyclohexanone, among other gases. The beauty of these sensors is that they are really cheap. You put them up, they sit there, and then you come around and read them. Theres no wiring involved. Theres no power, says Timothy Swager, the John D. MacArthur Professor of Chemistry at MIT. You can get quite imaginative as to what you might want to do with a technology like this. Swager is the senior author of a paper describing the new sensors in the Proceedings of the National Academy of Sciences the week of Dec. 8. Chemistry graduate student Joseph Azzarelli is the papers lead author; other authors are postdoc Katherine Mirica and former MIT postdoc Jens Ravnsbaek. Versatile gas detection For several years, Swagers lab has been developing gas-detecting sensors based on devices known as chemiresistors, which consist of simple electrical circuits modified so that their resistance changes when exposed to a particular chemical. Measuring that change in resistance reveals whether the target gas is present. Unlike commercially available chemiresistors, the sensors developed in Swagers lab require almost no energy and can function at ambient temperatures. This would allow us to put sensors in many different environments or in many different devices, Swager says. The new sensors are made from modified near-field communication (NFC) tags. These tags, which receive the little power they need from the device reading them, function as wirelessly addressable barcodes and are mainly used for tracking products such as cars or pharmaceuticals as they move through a supply chain, such as in a manufacturing plant or warehouse. NFC tags can be read by any smartphone that has near-field communication capability, which is included in many newer smartphone models. These phones can send out short pulses of magnetic fields at radio frequency (13.56 megahertz), inducing an electric current in the circuit on the tag, which relays information to the phone. To adapt these tags for their own purposes, the MIT team first disrupted the electronic circuit by punching a hole in it. Then, they reconnected the circuit with a linker made of carbon nanotubes that are specialized to detect a particular gas. In this case, the researchers added the carbon nanotubes by drawing them onto the tag with a mechanical pencil they first created in 2012 (http://newsoffice.mit.edu/2012/drawing-with-a-carbon-nanotube-pencil-1009), in which the usual pencil lead is replaced with a compressed powder of carbon nanotubes. The team refers to the modified tags as CARDs: chemically actuated resonant devices. When carbon nanotubes bind to the target gas, their ability to conduct electricity changes, which shifts the radio frequencies at which power can be transferred to the device. When a smartphone pings the CARD, the CARD responds only if it can receive sufficient power at the smartphone-transmitted radio frequencies, allowing the phone to determine whether the circuit has been altered and the gas is present. Current versions of the CARDs can each detect only one type of gas, but a phone can read multiple CARDs to get input on many different gases, down to concentrations of parts per million. With the current version of the technology, the phone must be within 5 centimeters of the CARD to get a reading, but Azzarelli is currently working with Bluetooth technology to expand the range. Widespread deployment The researchers have filed for a patent on the sensing technology and are now looking into possible applications. Because these devices are so inexpensive and can be read by smartphones, they could be deployed nearly anywhere: indoors to detect explosives and other harmful gases, or outdoors to monitor environmental pollutants. Once an individual phone gathers data, the information could be uploaded to wireless networks and combined with sensor data from other phones, allowing coverage of very large areas, Swager says. The researchers are also pursuing the possibility of integrating the CARDs into smart packaging that would allow people to detect possible food spoilage or contamination of products. Swagers lab has previously developed sensors (http://newsoffice.mit.edu/2012/fruit-spoilage-sensor-0430) that can detect ethylene, a gas that signals ripeness in fruit. Avoiding food waste currently is a very hot topic; however, it requires cheap, easy-to-use, and reliable sensors for chemicals, e.g., metabolites such as ammonia that could indicate the quality of raw food or the status of prepared meals, says Wolfgang Knoll, a managing director of the Austrian Institute of Technology, who was not part of the research team. The concept presented in this paper could lead to a solution for a long-lasting need in food quality control. The CARDs could also be incorporated into dosimeters to help monitor worker safety in manufacturing plants by measuring how much gas the workers are exposed to. Since its low-cost, disposable, and can easily interface with a phone, we think it could be the type of device that someone could wear as a badge, and they could ping it when they check in in the morning and then ping it again when they check out at night, Azzarelli says. The research was funded by the U.S. Army Research Laboratory and the U.S. Army Research Office through the MIT Institute for Soldier Nanotechnologies; the MIT Deshpande Center for Technological Innovation; and the National Cancer Institute. Source: MIT News Office (http://newsoffice.mit.edu/2014/wireless-chemical-sensor-for-smartphone-1208)
Nanoporous metals foam-like materials that have some degree of air vacuum in their structure have a wide range of applications because of their superior qualities. They posses a high surface area for better electron transfer, which can lead to the improved performance of an electrode in an electric double capacitor or battery. Nanoporous metals offer an increased number of available sites for the adsorption of analytes, a highly desirable feature for sensors. Lawrence Livermore National Laboratory (LLNL) and the Swiss Federal Institute of Technology (ETH) researchers have developed a cost-effective and more efficient way to manufacture nanoporous metals over many scales, from nanoscale to macroscale, which is visible to the naked eye. The process begins with a four-inch silicon wafer. A coating of metal is added and sputtered across the wafer. Gold, silver and aluminum were used for this research project. However, the manufacturing process is not limited to these metals. Next, a mixture of two polymers is added to the metal substrate to create patterns, a process known as diblock copolymer lithography (BCP). The pattern is transformed in a single polymer mask with nanometer-size features. Last, a technique known as anisotropic ion beam milling (IBM) is used to etch through the mask to make an array of holes, creating the nanoporous metal. During the fabrication process, the roughness of the metal is continuously examined to ensure that the finished product has good porosity, which is key to creating the unique properties that make nanoporous materials work. The rougher the metal is, the less evenly porous it becomes. During fabrication, our team achieved 92 percent pore coverage with 99 percent uniformity over a 4-in silicon wafer, which means the metal was smooth and evenly porous, said Tiziana Bond, an LLNL engineer who is a member of the joint research team. The team has defined a metric based on a parametrized correlation between BCP pore coverage and metal surface roughness by which the fabrication of nanoporous metals should be stopped when uneven porosity is the known outcome, saving processing time and costs. The real breakthrough is that we created a new technique to manufacture nanoporous metals that is cheap and can be done over many scales avoiding the lift-off technique to remove metals, with real-time quality control, Bond said. These metals open the application space to areas such as energy harvesting, sensing and electrochemical studies. The lift-off technique is a method of patterning target materials on the surface of a substrate by using a sacrificial material. One of the biggest problems with this technique is that the metal layer cannot be peeled off uniformly (or at all) at the nanoscale. Other applications of nanoporous metals include supporting the development of new metamaterials (engineered materials) for radiation-enhanced filtering and manipulation, including deep ultraviolet light. These applications are possible because nanoporous materials facilitate anomalous enhancement of transmitted (or reflected) light through the tunneling of surface plasmons, a feature widely usable by light-emitting devices, plasmonic lithography, refractive-index-based sensing and all-optical switching. The other team members include ETH researcher Ali Ozhan Altun and professor Hyung Gyu Park. The teams findings were reported in an article titled Manufacturing over many scales: High fidelity macroscale coverage of nanoporous metal arrays via lift-off-free nanofrabication. (http://onlinelibrary.wiley.com/doi/10.1002/admi.201400084/abstract) It was the cover story in a recent issue of Advanced Materials Interfaces. Source: Lawrence Livermore National Laboratory (https://www.llnl.gov/news/lawrence-livermore-researchers-develop-efficient-method-produce-nanoporous-metals)