National Nanomanufacturing Network

New process allows fully additive roll-to-roll printing of flexible electrochromic devices

National Nanomanufacturing Network - September 17, 2014 - 5:26am
Electrochromic materials exhibit reversible optical change in the visible region when they are subjected to an electric charge. These switchable materials can be used for 'smart' windows in buildings, cars and airplanes as well as in information displays and eye wear. An electrochromic device is one of the most attractive candidates for paper-like displays, so called electronic paper, which will be the next generation display, owing to attributes such as thin and flexible materials, low-power consumption, and fast switching times. Electrochromic devices (ECDs) generally consist of a structure where certain material layers, among them an electrolyte, are sandwiched together. A major limitation until now has been the necessity to use the very expensive indium tin oxide (ITO) as transparent electrodes. ITO's brittleness makes it unsuitable for flexible device applications and its fabrication process – vacuum-coating, high-temperature annealing – is incompatible with plastic-based substrates. "ECD structure and manufacturing is to a wide extent challenged by the electrolyte component," Frederik C. Krebs (http://www.dtu.dk/english/Service/Phonebook/Person?id=3454), a professor and head of section of Energy Conversion and Storage at the Technical University of Denmark, tells Nanowerk. "As it remains common practice to employ a semisolid adhesive gel electrolyte, fabrication of devices is limited to separately coating of the two electrodes before finalizing the device in a lamination step; a technical challenge in a simple roll-to-roll (R2R) process and an impossibility in advanced R2R processes with 2D registration requirements." In new work, reported in the September 5, 2014 online edition of Advanced Materials ("From the Bottom Up – Flexible Solid State Electrochromic Devices" (http://dx.doi.org/doi:10.1002/adma.201402771)), Krebs and first author Dr. Jacob Jensen describe solid state electrochromic devices, manufactured by sequentially stacking layers in one direction using flexographic printing and slot-die coating methods. The novelty of this bottom-up printing process for electrochromic device fabrication is the use of printed grid structures in combination with printable electrolytes that can be crosslinked in such a way that many layers can be printed on top of each other. Whereas previous processes have employed the lamination of two separately prepared films, this new method provides the ability to constitute multilayer structures with functionality through printing layers consecutively on top of each other. "We show how – using a specially developed 'curing chamber' mounted on a mini roll coater – solid state electrochromic devices can be manufactured continuously in one direction, i.e., from the bottom and up, using slot-die coating and flexographic printing," says Krebs. "This technique eliminates the need for a lamination step and enables fully additive roll-to-roll processes." This considerably simplified process constitutes an important step towards R2R manufacturing of ECDs without having to employ brittle materials such as ITO. This new paper extends the team's previous reports on ECD manufacture such as "Fast Switching ITO Free Electrochromic Devices" (http://dx.doi.org/doi:10.1002/adfm.201302320) in Advanced Functional Materials and "Manufacture and Demonstration of Organic Photovoltaic-Powered Electrochromic Displays Using Roll Coating Methods and Printable Electrolytes" (http://dx.doi.org/doi:10.1002/polb.23038) in the Journal of Polymer Science. The ability to cheaply mass-produce ECDs will find applications ranging from light management and shading to large area/low cost displays such as billboards. Basically, it is a simple way of printing thin, very low cost and low power consumption display devices. The compromises that need to be made with this process are slow switching speed and relatively poor contrast. Both can be improved, notes Krebs, but since these devices rely on a chemical reaction taking place when changing color there are limits to the switching speed that can be reached. Krebs points out that the current version of his team's ITO- and vacuum-free grid electrodes still require further optimization to achieve the same optical transmission as the brittle ITO. Source: Nanowerk (http://www.nanowerk.com/spotlight/spotid=37388.php)

Nanoscale Offset Printing System (NanoOPS) Offers Potentially Transformative Nanomanufacturing ...

National Nanomanufacturing Network - September 10, 2014 - 9:53am
The Northeastern University’s NSF Nanoscale Science and Engineering Center for High-rate Nanomanufacturing (CHN) has developed a fully-automated system that uses offset-type printing technologies at the nanoscale to make products that fully take advantage of the superior properties of nanomaterials. In minutes, the system can print metals, organic and inorganic materials, polymers, and nanoscale structures and circuits (down to 25 nanometers) onto flexible or inflexible substrates. The Nanoscale Offset Printing System (NanoOPS) is a new system that has the potential to transform nanomanufacturing and spur innovation. Because of its relative simplicity, NanoOPS is expected to eliminate some of the high cost entry barriers to the fabrication of nanoscale devices for electronics, energy, medical, and functional materials applications. Current nanofabrication facilities cost billions of dollars to build, and their operation requires massive quantities of water and power. NanoOPS could operate at a fraction of the cost, making nanomanufacturing accessible to innovators and entrepreneurs, and creating the potential for a wave of creativity, perhaps similar to what the PC did for computing and what the 3D printer is doing for design. In addition to reducing manufacturing costs, NanoOPS will go beyond current fabrication capabilities by enabling the commercialization of products enabled by the properties of nanoscale materials, such as nanotubes, that have been demonstrated in laboratory settings. This will enable critical manufacturing in areas such as new and more affordable medicines; stronger, lighter building materials; or faster, cheaper electronics. NanoOPS was designed jointly by the CHN team and Milara, a Massachusetts-based manufacturer of specialized equipment for the semiconductor industry, and subsequently built by Milara. This enables industry and innovators access to unique, emerging nanoscale process tools transitioning directly from a NSF NSEC. This exciting development provides a prime example of the new emphasis on science and technology investments by the federal government effectively transitioning to impact the commercial sector. The CHN will be hosting a NanoOPS Demonstration to be held on September 17, 2014 at Northeastern University’s Burlington, MA campus. Please contact Eric Howard, eric.howard@neu.edu (mailto:eric.howard@neu.edu) or check out http://nano.server281.com/nanoops-day/ (http://nano.server281.com/nanoops-day/) for more details or to RSVP to this event.

NanoBCA Interview with Allen Gelwick, Executive VP, Lockton Companies

National Nanomanufacturing Network - September 3, 2014 - 5:46am
The NanoBCA conducted an interview on August 27, 2014 with Allen Gelwick, Executive VP of Lockton Companies. Mr. Gelwick is one of America’s leading insurance experts and has been an active participant in the nano community for over a decade. NanoBCA: Historically, how has the insurance sector dealt with nanotechnology? Mr. Gelwick: The insurance industry thus far has essentially dealt with nanotechnology by taking a “wait and see” approach. This is not unusual as the nature of insurance is to look retrospectively at events to determine how to set policies and rates. The challenge here is that nanotechnology is an emerging technology with little or no history. Thus, insurers cannot use the past to accurately predict future events. A basic tenant of the insurance sector is to rely on accurate predictive capabilities, which simply do yet not exist for nanotechnology. NanoBCA: Are there any steps that the insurance sector can take while waiting for data? Mr. Gelwick: Without the benefit of adequate historical data, the insurance sector has done its best to try to develop an understanding of risks associated with nanotechnology. To that end, risk control experts and actuaries from the major insurance carriers have engaged in nanotech specific conferences and meetings for over a decade with the intention to better understand risks associated with this emerging technology. They have also looked to government agencies for guidance. NanoBCA: Why can’t an insurer just make an educated guess and then revise rates as the data become available? Mr. Gelwick: Actuarial science is the discipline used by insurance companies to establish pricing. It’s a data driven discipline that does not lend itself to the flexibility you suggest. However, there are some actuaries who believe that emerging risk can and should be quantified. This creates somewhat of double-edge sword for insurers which could result in increases in reserves by the insurer, adversely impacting the insurers ability to remain competitive, in order to cover the risk. NanoBCA: If my nanotech company today has a standard policy, am I not already covered to some extent regarding risks arising from nanotechnology? Mr. Gelwick: There has been growing discussion in the insurance sector regarding the potential coverage implications due to specific existing coverages such as Products Liability, Workers Compensation, Health, Professional liability and Environmental liability. While there is not a specific “nanotechnology” exclusion written into the policy, Products, Liabilities, and Professional Liability (D O, Medical Malpractice, EPO, etc) should raise a serious concern to the insurers as well as the company and their investors. Health coverages are likely to assume a majority of the emerging health risks. The good news is our health plans and workers compensation policies should continue to respond. Some of the insurance industry articles have discussed products recall as an exposure, but this exposure is not generally covered by insurance and instead remains a specialty coverage. Perhaps most surprising is that neither health insurers nor state-funded Workers Compensation carriers have become vocal yet on the implications of this emerging technology. Those two will likely have the greatest share of liability. NanoBCA: Risks that are akin to those contemplated with a nanomaterial have been around for a long time, say for instance in the chemicals sector. Are there not established mechanisms in the insurance sector to deal with such risks? Mr. Gelwick: This is a good segue into why coverage should be reviewed. Unlike most professional liability and environmental policies that generally incorporate a "claims-made" coverage trigger, most U.S. products liability policies currently use an "occurrence" coverage trigger.We are now getting into some nuances that I am happy to discuss with anyone who is interested to dig deeper on this topic. Suffice it to say that there are significant pricing and potential liability dollar amounts that result from the type of coverage trigger. I will be covering this topic in more detail in some upcoming publications. NanoBCA: One last question on this topic: you mentioned “U.S.” policies; are European policies different? Mr. Gelwick: To some extent, yes. “Claims-made” coverage for products and completed operations is common in Europe, but not in the U.S. NanoBCA: What, if anything, is being reported in the insurance sector literature on the topic of nanotechnology? Mr. Gelwick: Articles on the topic of nanotechnology risk generally convey that a steep learning curve is underway and that the regulatory framework, which will govern nanotechnology, is still a work in progress. There are excellent high level and introductory articles offering views on this promising technology that, to date, come mostly from global insurers such as Allianz, ACE, Chubb, Gen Re, Lloyds, Swiss Re, and Zurich etc. However, very few of these publications have yet to discuss potential coverage issues. NanoBCA: Does a nano-specific policy exist yet in the marketplace? Mr. Gelwick: AIG's licensed non-admitted carrier, Lexington Insurance, is the first carrier to offer a nano-specific coverage, known as “LexNano Shield.” Another surplus lines carrier (a licensed non-admitted carrier in the U.S. - meaning they operate outside of any state guarantee funds and are essentially unregulated as it relates to coverage), James River, is also willing to underwrite and cover some nanotechnology related risks. Aspen currently incorporates nanotechnology questions that if addressed can affirm coverage. And finally, Zurich developed its “ZNEPtm” protocol to underwrite nanotechnology exposures. NanoBCA: Sounds like progress is being made to address some of the concerns you mentioned above? Mr. Gelwick: Yes, but as an aside, Lexington continues to advise companies in the nano space save the $5,000 or more per year by rolling the dice that there are no nano specific coverage exclusions (and perceive that retaining “Occurrence” coverage will protect them.) This is a bet, that if wrong, could impair an exit strategy or otherwise adversely impact your investors. No doubt that entrepreneurs will take risks. And, when it works out, we tend to romanticize this behavior. When it does not work out, however, investors and the public are at risk. A difference between Europe and the U.S. is that regulations are already being implemented in Europe and the public demands that risks are assessed before products are introduced to the marketplace. Regulations in the U.S. are inevitably coming, but as stated previously, the sector is largely unregulated currently and insurers are in a reactive mode rather than a proactive mode. NanoBCA: Do insurers use “nanotechnology” as a classification for coverage analysis, or do they look at more distint categorization? Mr. Gelwick: The insurance industry, like regulators and scientists, continue to argue over the definition of nanotechnology. While this discussion focuses on nanotechnology, we should note that chemicals also remain largely uncharacterized. Insurers therefore usually require a “Claims-made” coverage trigger to address their inability to assess the risks of long-term exposures to certain chemicals. From an underwriting standpoint, and with a lack of an adequate regulatory framework, insurers are applying protocols often adapted from the chemical, medical and environmental exposures to underwrite emerging technologies. An example of how underwriters can underwrite in the absence of specific classifications is Zurich's “ZNEPtm”. NanoBCA: What specific questions about nanomaterials are insurers most concerned about? Mr. Gelwick: Every article that I have seen suggests that toxicological assessments of nanomaterials are broadly needed. And although a tremendous amount of funding has been expended to develop nanomaterials, the smallest portion of that funding has been assigned to understanding risk. For instance, we find that very few nanomaterials have been characterized for EHS purposes. Further, a smaller percentage of those have been independently evaluated by toxicologists for impacts on workers, consumers and the environment. Without such evaluation, I believe there exists a false sense of security for us all. NanoBCA: Can you sum this up for us more in layman’s terms? Mr. Gelwick: Keep in mind that insurance is simply a method to finance business risk. Insurance carriers and risk practices use risk identification as a necessary first step, then they measure the risks identified, as best they can, to determine the cost of risk transfer through insurance. Any business should use a similar process to decide whether to transfer the risk to a qualified insurer, or alternatively to retain the risk. NanoBCA: So, it sounds like you are saying that many companies do not do this? Mr. Gelwick: Well, we can start by acknowledging that less than 100 nanomaterials have been characterized, yet there are in active development. Universities, where a majority of the research is conducted, have proven to be very reluctant to allow independent safety assessments of their nanomaterial laboratory activities. Small companies tend to not have the funds necessary to properly assess nanosafety, or at least they perceive the cost as too expensive. And, larger companies, like Johnson Johnson, tend to be self-insured and may or may not have an understanding of the risks including risks to supply chains upon which they rely. NanoBCA: As you mentioned previously though, insurance policies do, to some extent, currently cover risks associated with nanotechnologies? Mr. Gelwick: Generally, the structure of the policies relevant here are classified as “occurrence” policies which means that if you have a policy for year 2014, then any claim in future years (say, in 2018) that points to an event in 2014, will be covered by the terms of the policy as it existed in 2014. (Note: every state has different laws in this regard which creates a level of complexity). So, for illustration sake, if an “occurrence” policy does not exclude nano, then in many states, plaintiffs’ attorneys would be able to sue for every single year, under a separate policy for each year, that a suspect material was produced. This creates a scenario where multiple claims are possible. That is why the “occurrence” coverage trigger vs. the “claims made” coverage trigger presents such significantly different financial consequences. NanoBCA: So, is this scenario bad for the insured, or the insurer, or both? Mr. Gelwick: Any ambiguity usually works to the benefit of the insured. Thus, it is commonly believed that this is ultimately a problem for the insurer. However, the reality is that this scenario will likely hurt the insured more because the company may end up in a situation, post claim, that it can not find an insurer that will provide coverage at an acceptable costmoving forward from any claims which, as mentioned above, could also impact exit strategies for investors. As claims increase, insurers will predictably evolve to either limiting coverage or creating exclusions. NanoBCA: You make a good point. But, what “claims” are out there currently? Mr. Gelwick: Of current significance is the recent hip replacement claims against Johnson Johnson and its subsidiaries. These claims account for over $4 billion in offered settlements by Johnson Johnson. You can bet that plaintiff attorneys are considering this as a template for future litigation on other products. NanoBCA: Aren’t the insurers incentivized to figure out a way to create a market to sell nano specific policies, and to control risks associated therewith? Mr. Gelwick: Yes, and they are working on it. For starters, the reinsurance sector will likely begin inserting and requiring answers to nanomaterial specific questions to assist with the underwriting process. This will force the applicant to answer difficult risk questions associated with nanomaterials. Since nanomaterials are rarely disclosed, yet are commonly incorporated into products, it is currently almost impossible for insureds to answer these questions completely. Failure to do so, however, will likely create coverage gaps, particularly as it relates to supply chain risk. This process will, in some instances, evolve to create insurance exclusions. However, where enough understanding and data is available, buy-back policies or endorsements will likely become available. NanoBCA: Is there a precedent for this seemingly awkward point in time that we are in with regard to nanotech and insurance? Mr. Gelwick: Most would cite asbestos and the evolution of pollution exclusions, but this in my view this is too narrow a focus and assumes the worst when it is more likely that only a limited percentage of nanotechnology will equate to this level of risk. In fact, nanotechnology will likely help reduce risks in the future, as evidenced by nano enabled products that can clean-up pollution. However, I agree with some observers who believe that we are in unchartered territory as the number of new and innovative chemicals, not to even mention nanomaterials,that have recently been introduced into commerce is growing at a steep exponential rate. Risks are not yet known as to most of these. Michael Depledge, the former Chief Scientific Advisor of the UK Government’s Environment Agency, gave a presentation on point this June in London at the Royal Institute for EMTECH, an emerging fund being created to invest in emerging technologies. He offered two slides that from an insurance standpoint help us consider emerging risk from a historical standpoint. Those slides illustrated that the lag time from the introduction of any new technology to the adequate recognition and understanding of associated risks is generally about 10 years. The number of new chemicals and materials has experienced truly “off-the-charts” exponential growth in the 21st Century. What the future holds in terms of risk is literally growing faster than we can possibly fathom. NanoBCA: So, how do you manage this increase of unknown risks? Mr. Gelwick: Insurance companies will simply have to increase the size of their reserve funds to offset incurred and unknown risks on these new materials because they may likely have to pay claims on them down the line. NanoBCA: Any other observations to share regarding the future of nanotechnology risk insurance? Mr. Gelwick: People often ask me if insurers will simply exclude nanotechnology. Nanotechnologies have been in the stream of commerce now for over ten years and, to date, only one insurance company that we know of has put an exclusion on nanotechnology. But things are changing rapidly. Most insurance companies are starting to consider nanotechnology through their underwriting groups already supporting high hazard classes of business such as chemical companies or environmental exposures. The analysis of insuring consumable products will follow except to the extent the exposures are covered by regulatory agencies such as the FDA. Ultimately, nanotechnology will be incorporated into all realms of insurance risk assessment and coverage. NanoBCA: What do you see as the toughest questions emerging in the arena of nanotechnology risk and liability? Mr. Gelwick: How do you exclude something from a policy if even the applicant doesn’t know that the risk exists? There are many risks that we just simply do not know yet. How does that play out in court? Can those risks legally be excluded? Probably not, but these things will play out in court. And that will take some time. NanoBCA: So, what conclusions, if any, can we make about the future course of insurance for nano? Mr. Gelwick: I would conclude that there will continue to be a lot of confusion in the future, at least the near future – 5 to 10 years. It seems logical to me that insurers might shift Products, Liability from the “occurrence coverage” model to a “claims made coverage” model as discussed earlier. The advantage of the “claims made” model is to limit the cost of distracting and expensive litigation. This model really appears to be best suited for an emerging technology with unknown risks, such as nanotechnology. Insurers will need to broaden tail coverage to be able to offer reasonable pre-agreed pricing for tail coverage and to structure these policies to reflect the different statute of repose for different states providing confidence to the insured. This enables a more sustainable economic model for all stakeholders. NanoBCA: What role will the pending hip replacement class action products liability lawsuits have on the insurance sector? Mr. Gelwick: Frankly, I see the hip replacement litigation serving as a roadmap for more claims from the plaintiffs’ bar. They will not only look prospectively at new products and new claims, but will also look retrospectively at the possibility of adding nanotech specific claims to products produced over the past ten or so years. Each day that we as a nanotech business community fail to address issues we have discussed today, simply benefits those who make their livings from litigation. NanoBCA: Do you attach any historical significance to this hip replacement litigation? Mr. Gelwick: Yes, I think we are indeed at a watershed moment. Previously there have not been any claims against insurance policies, or allegations contained in lawsuits, that specifically cite “nano” anything. This hip replacement litigation, which is resulting in settlements in the billions of dollars, is the first to identify “nano” as a specific allegation of causation. Note that only the surface of the hip incorporated nanotechnology, yet it appears to be the proximate cause of loss. This is significant because it serves to educate the plaintiffs’ bar that nanomaterials exist and may be a component of causation, and thus liability, of other products in the future (and the past). Also, given what we know about the huge volume of products in the flow of commerce that include nanomaterials, it is reasonable to assume that this hip replacement litigation is the first of many to come that will implicate nanomaterials. NanoBCA: This is all very enlightening and confusing at the same time. As you say, confusion is likely to reign for a while longer. With that in mind, should nanomaterials companies seek insurance coverage today? And, how would they get it? Mr. Gelwick: Yes, nanomaterials companies should absolutely seek coverage. If anything, the hip replacement litigation shows us that liability is very real and that it can be extremely expensive to find yourself as a defendant in a products liability and recall action without coverage to the point that it could easily destroy companies that do not have a good risk strategy plan in place. I hope and suspect that the nanomaterial producer, or producers, for Johnson Johnson had a contract(s) holding them harmless, or their business(es) could be in jeopardy. So, use of contracts to mitigate its risks become critical. We also now know that taking the approach of “putting your head in the sand” to feign ignorance will be no match in a court of law against the reasonableness standard of independently assessing safety. From an insurance standpoint this will trigger a common coverage exclusion “expected or intended” creating grounds for an insurance carrier to deny coverage. A more prudent approach, in my estimation, would be for companies to pursue “Claims-made” coverage, broadened from traditional offerings as we discussed, to affirm there is coverage for nanomaterials that are known and to include those materials the insured can be reasonably held to have known contained nanomaterials. And, companies should make efforts to fully understand, to the extent possible, the nano risks associated with their business and products. This would include toxicological analysis and data regarding risks to their workers, consumers, and the environment. Ultimately this understanding and data will be very useful because insurers (as well as current shareholders and future investors) are going to demand answers to these questions. Moreover, EPA requires this data for approval of manufacturing and sales of nanomaterials in the U.S. Larger companies that utilize nanomaterials from third parties are also at risk. They are likely not aware of whether a supply chain risk exists that may seriously disrupt their production schedules. These large companies may want to consider purchasing aggregate stops on their large retention cash flow programs.

Advanced Nanomanufacturing at the Core of Potential New DARPA Program

National Nanomanufacturing Network - August 28, 2014 - 5:03am
The benefits of nanotechnology and nanomanufacturing include significantly improved properties of many common materials when fabricated at nanoscale or molecular dimensions. Examples of these properties include quantized electrical characteristics, enhanced adhesion and surface properties, superior thermal, mechanical, and chemical properties, and tunable light absorption and scattering. Scaling these properties for nano-enabled products and systems, could offer potentially revolutionary performance and capabilities for defense, security, and commercial applications while providing significant societal and economic impact. Key challenges and barriers remain to realizing such nano-enabled technologies that are central to emerging nanomanufacturing techniques, including retaining the nanoscale properties in materials at larger scales, and the maturity of assembly techniques for structures between the nanoscale and 100 microns. Recently, the Defense Advanced Research Project Agency (DARPA) has created the Atoms to Product (A2P) program to address and help overcome these challenges. The program seeks to develop enhanced technologies for assembling nanoscale elements coupled with integration and scale-up of these components into materials and systems to product scale in ways that preserve and exploit the distinctive nanoscale properties of the core element. “We want to explore new ways of putting incredibly tiny things together, with the goal of developing new miniaturization and assembly methods that would work at scales 100,000 times smaller than current state-of-the-art technology,” said John Main (http://www.darpa.mil/Our_Work/DSO/Personnel/Dr__John_Main.aspx), DARPA program manager, quoted from the DARPA website announcement (http://www.darpa.mil/NewsEvents/Releases/2014/08/22.aspx). “If successful, A2P could help enable creation of entirely new classes of materials that exhibit nanoscale properties at all scales. It could lead to the ability to miniaturize materials, processes and devices that can’t be miniaturized with current technology, as well as build three-dimensional products and systems at much smaller sizes.” The A2P program supports the emphasis on key challenges of nanomanufacturing for given applications extending previous investments in fundamental science and materials research. In this case, several emerging nanomanufacturing approaches and platforms are likely to contribute to such a program concept, including nanoimprint lithography, directed self-assembly (DSA), layer-by-layer (LBL) assembly, additive driven assembly, and hybrid processes incorporating solution-based and vacuum-based processing approaches. Further scalability through adaptation to existing manufacturing infrastructure such as roll-to-roll and print, additive manufacturing, or semiconductor “batch” type processing is likely to accelerate the pathway to commercialization, and further position these emerging nanomanufacturing processes for the eventual Factory of the Future. To familiarize potential participants with the technical objectives of the A2P program, DARPA has scheduled identical Proposers Day webinars. Participants must register through the registration website: DARPA (http://www.darpa.mil/NewsEvents/Releases/2014/08/22.aspx)

Large Area Growth of Single Layer Hexagonal Boron Nitride Films

National Nanomanufacturing Network - August 28, 2014 - 4:29am
Two-dimensional hexagonal boron nitride (h-BN) is a material of significant interest due to the strong ionic bonding of boron and nitrogen atoms that provides unique properties, including the thinnest insulating nanomaterial, exhibiting a bandgap of 5.9 eV, with superior chemical, mechanical, and thermal stability. In addition, h-BN provides an ideal substrate for improving the electrical properties of graphene since the surface is atomically smooth and free of dangling bonds, thereby reducing charge scattering effects resulting in an order of magnitude increase in graphene charge mobility over materials grown on silicon or silicon dioxide. Previously, the method to synthesize monolayer n-BN utilized ultra-high vacuum chemical vapor deposition (UHVCVD) using borazine as a precursor on single crystal transition metal substrates, such as nickel, platinum, or silver, but proved difficult to scale. Polycrystalline metal foils (Ni, Co, Cu, and Pt) were additionally used to grow h-BN using regular chemical vapor deposition (CVD), but the thickness and quality of the films critically depended on surface morphology and crystal orientation of the substrate. High quality h-BN has been synthesized on Pt foils using ammonia borane precursor, yet control of film thickness and domain size remains a challenge for scaling, and the specific growth mechanisms are not well understood. Recently, Park et.al., reported results from a systematic study for synthesis of large area single layer h-BN films on polycrystalline Pt foils using low pressure CVD comparing borazine and ammonia borane precursors. The authors’ goal was to study the effect of the Pt lattice orientation, the total pressure, and the different cooling rate in order to understand h-BN growth mechanisms. Since nitrogen is not soluble in Pt, the authors’ objective was to confirm the contributions to h-BN growth surface mediated and precipitation processes. The study included analysis of film properties dependence on cooling rate and crystal orientation of the substrate. Their findings demonstrated that film growth was by a surface mediated growth mechanism, facilitated by a catalytic reaction, that produced polycrystalline h-BN monolayers confined by the underlying Pt surface orientation. The thickness of the h-BN films exhibited a dependence on the Pt surface orientation, presumably determined by the available catalytic reaction sites that decompose the borazine precursor, which would exhibit a dependence on crystal orientation. Improved understanding of h-BN growth mechanisms will potentially lead to methods for controlling the growth of high-quality h-BN films. This further provides the basis for materials and substrates for application in quantum tunneling devices, novel heterostructures, and two-dimensional semiconductors such as molybdenum sulfide and graphene.Reference: Park J, Park JC, Yun SJ, Kim H, Luong DH, Kim SM, Choi SH, Yang W, Kong J, Kim KK, Lee YH. Large-Area Monolayer Hexagonal Boron Nitride on Pt Foil. ACS Nano. 2014; 8 (8): 8520-852 doi: 10.1021/nn503140y (http://pubs.acs.org/doi/full/10.1021/nn503140y#showRef) Image reprinted with permission from American Chemical Society.

Nanotechnology engineering produces a water splitter that runs on an ordinary AAA battery

National Nanomanufacturing Network - August 27, 2014 - 4:56am
In 2015, American consumers will finally be able to purchase fuel cell cars from Toyota and other manufacturers. Although touted as zero-emissions vehicles, most of the cars will run on hydrogen made from natural gas, a fossil fuel that contributes to global warming. Now scientists at Stanford University have developed a low-cost, emissions-free device that uses an ordinary AAA battery to produce hydrogen by water electrolysis. The battery sends an electric current through two electrodes that split liquid water into hydrogen and oxygen gas. Unlike other water splitters that use precious-metal catalysts, the electrodes in the Stanford device are made of inexpensive and abundant nickel and iron. "Using nickel and iron, which are cheap materials, we were able to make the electrocatalysts active enough to split water at room temperature with a single 1.5-volt battery," said Hongjie Dai (http://dailab.stanford.edu/), a professor of chemistry at Stanford. "This is the first time anyone has used non-precious metal catalysts to split water at a voltage that low. It's quite remarkable, because normally you need expensive metals, like platinum or iridium, to achieve that voltage." In addition to producing hydrogen, the novel water splitter could be used to make chlorine gas and sodium hydroxide, an important industrial chemical, according to Dai. He and his colleagues describe the new device in a study (http://dx.doi.org/10.1038/ncomms5695) published in the Aug. 22 issue of the journal Nature Communications. The promise of hydrogen Automakers have long considered the hydrogen fuel cell a promising alternative to the gasoline engine. Fuel cell technology is essentially water splitting in reverse. A fuel cell combines stored hydrogen gas with oxygen from the air to produce electricity, which powers the car. The only byproduct is water – unlike gasoline combustion, which emits carbon dioxide, a greenhouse gas.Earlier this year, Hyundai began leasing fuel cell vehicles in Southern California. Toyota and Honda will begin selling fuel cell cars in 2015. Most of these vehicles will run on fuel (http://energy.gov/eere/fuelcells/natural-gas-reforming) manufactured at large industrial plants that produce hydrogen by combining very hot steam and natural gas, an energy-intensive process that releases carbon dioxide as a byproduct. Splitting water to make hydrogen requires no fossil fuels and emits no greenhouse gases. But scientists have yet to develop an affordable, active water splitter with catalysts capable of working at industrial scales. "It's been a constant pursuit for decades to make low-cost electrocatalysts with high activity and long durability," Dai said. "When we found out that a nickel-based catalyst is as effective as platinum, it came as a complete surprise." Saving energy and money The discovery was made by Stanford graduate student Ming Gong, co-lead author of the study. "Ming discovered a nickel-metal/nickel-oxide structure that turns out to be more active than pure nickel metal or pure nickel oxide alone," Dai said. "This novel structure favors hydrogen electrocatalysis, but we still don't fully understand the science behind it." The nickel/nickel-oxide catalyst significantly lowers the voltage required to split water, which could eventually save hydrogen producers billions of dollars in electricity costs, according to Gong. His next goal is to improve the durability of the device. "The electrodes are fairly stable, but they do slowly decay over time," he said. "The current device would probably run for days, but weeks or months would be preferable. That goal is achievable based on my most recent results" The researchers also plan to develop a water splitter than runs on electricity produced by solar energy. "Hydrogen is an ideal fuel for powering vehicles, buildings and storing renewable energy on the grid," said Dai. "We're very glad that we were able to make a catalyst that's very active and low cost. This shows that through nanoscale engineering of materials we can really make a difference in how we make fuels and consume energy."Source: Stanford University (http://news.stanford.edu/news/2014/august/splitter-clean-fuel-082014.html)

Optical Microscope Technique Confirmed as Valid Nano-Measurement Tool

National Nanomanufacturing Network - August 27, 2014 - 4:20am
Recent experiments have confirmed* that a technique developed several years ago at the National Institute of Standards and Technology (NIST) can enable optical microscopes to measure the three-dimensional (3-D) shape of objects at nanometer-scale resolution—far below the normal resolution limit for optical microscopy (about 250 nanometers for green light). The results could make the technique a useful quality control tool in the manufacture of nanoscale devices such as next-generation microchips. NIST’s experiments show that Through-focus Scanning Optical Microscopy (TSOM) is able to detect tiny differences in 3-D shapes, revealing variations of less than 1 nanometer in size among objects less than 50 nm across. Last year,** simulation studies at NIST indicated that TSOM should, in theory, be able to make such distinctions, and now the new measurements confirm it in practice. “Up until this point, we had simulations that encouraged us to believe that TSOM could allow us to measure the 3-D shape of structures that are part of many modern computer chips, for example,” says NIST’s Ravi Attota, who played a major role in TSOM’s development. “Now, we have proof. The findings should be helpful to anyone involved in manufacturing devices at the nanoscale.” Attota and his co-author, Ron Dixson, first measured the size of a number of nanoscale objects using atomic force microscopy (AFM), which can determine size at the nanoscale to high accuracy. However, the great expense and relatively slow speed of AFM means that it is not a cost-effective option for checking the size of large numbers of objects, as is necessary for industrial quality control. TSOM, which uses optical microscopes, is far less restrictive—and allowed the scientists to make the sort of size distinctions a manufacturer would need to make to ensure nanoscale components are constructed properly. Attota adds that TSOM can be used for 3-D shape analysis without needing complex optical simulations, making the process simple and usable even for low-cost nanomanufacturing applications. “Removing the need for these simulations is another way TSOM could reduce manufacturing costs,” he says. More details on the TSOM technique and its application to 3-D electronics manufacturing can be found in this story (http://www.nist.gov/public_affairs/tech-beat/tb20130625.cfm#tsom), which covers the 2013 simulation study. *R. Attota and R.G. Dixson. Resolving three-dimensional shape of sub-50 nm wide lines with nanometer-scale sensitivity using conventional optical microscopes. Applied Physics Letters, 105, 043101, July 29, 2014, http://dx.doi.org/10.1063/1.4891676 (http://dx.doi.org/10.1063/1.4891676). **See the June 2013 NIST Tech Beat story, “Microscopy Technique Could Help Computer Industry Develop 3-D Components (http://www.nist.gov/public_affairs/tech-beat/tb20130625.cfm#tsom)” at www.nist.gov/public_affairs/tech-beat/tb20130625.cfm#tsom (http://www.nist.gov/public_affairs/tech-beat/tb20130625.cfm#tsom). Source: NIST (http://www.nist.gov/pml/div683/tsom-082614.cfm)

Graphene rubber bands could stretch limits of current healthcare, new research finds

National Nanomanufacturing Network - August 20, 2014 - 8:26am
New research published today in the journal ACS Nano ("Sensitive, High-Strain, High-Rate Bodily Motion Sensors Based on Graphene–Rubber Composites" (http://dx.doi.org/doi:10.1021/nn503454h)) identifies a new type of sensor that can monitor body movements and could help revolutionise healthcare. Although body motion sensors already exist in different forms, they have not been widely used due to their complexity and cost of production. Now researchers from the University of Surrey and Trinity College Dublin have for the first time treated common elastic bands with graphene, to create a flexible sensor that is sensitive enough for medical use and can be made cheaply. Once treated, the rubber bands remain highly pliable. By fusing this material with graphene - which imparts an electromechanical response on movement – the team discovered that the material can be used as a sensor to measure a patient's breathing, heart rate or movement, alerting doctors to any irregularities. "Until now, no such sensor has been produced that meets needs and that can be easily made. It sounds like a simple concept, but our graphene-infused rubber bands could really help to revolutionise remote healthcare," said Dr Alan Dalton from the University of Surrey. Co-author, Professor Jonathan Coleman from Trinity College, Dublin commented, "This stretchy material senses motion such as breathing, pulse and joint movement and could be used to create lightweight sensor suits for vulnerable patients such as premature babies, making it possible to remotely monitor their subtle movements and alert a doctor to any worrying behaviours. "These sensors are extraordinarily cheap compared to existing technologies. Each device would probably cost pennies instead of pounds, making it ideal technology for use in developing countries where there are not enough medically trained staff to effectively monitor and treat patients quickly." Source: University of Surrey (https://www.surrey.ac.uk/features/could-elastic-bands-monitor-patients%E2%80%99-breathing)

NSF Workshop for a Future Nanotechnology Infrastructure Support Program Webcast

National Nanomanufacturing Network - August 13, 2014 - 7:53am
On August 18 and 19, 2014 the NSF will conduct a Workshop for a Future Nanotechnology Infrastructure Support Program.The workshop is a next step in NSF's preparation for developing a program to succeed the National Nanotechnology Infrastructure Network (NNIN (http://nnin.org/)), after having received community input in response to a recent Dear Colleague Letter (DCL 14-068 (http://www.nsf.gov/pubs/2014/nsf14068/nsf14068.jsp?org=ENG)). To broaden engagement, portions of the Workshop for a Future Nanotechnology Infrastructure Support Program will be webcast. (The approximate webcast times shown below are Eastern Daylight Time.) The workshop will convene a panel of experts from academe, industry, and government to: develop a vision of how a future nanotechnology infrastructure support program could be structured, and determine the key needs for the broad user communities over the coming decade. The workshop is co-chaired by Dr. Thomas Theis (IBM Research, on assignment to the Semiconductor Research Corporation) and Dr. Mark Tuominen (University of Massachusetts, Amherst). More details are in the workshop agenda (http://www.nsf.gov/attachments/132127/public/Workshop_Future_Nanotechnology_Infrastructure_Support_Program.pdf). Webcast: August 18, 2014 8:00 AM to 12:00 PM and August 19, 2014 8:00 AM to 12:00 PM Morning sessions of the workshop will be broadcast via WebEx; afternoon breakout sessions will not be broadcast. If you have never used WebEx before or if you want to test your computer's compatibility with WebEx, please go to http://www.webex.com/lp/jointest/ (http://www.webex.com/lp/jointest/), enter the session information and click "Join". Please feel free to contact WebEx Support if you are having trouble joining the test meeting.Session number: 643 345 106 Session password: This session does not require a password. ------------------------------------------------------- To join the session ------------------------------------------------------- 1. Go to https://src.webex.com/src/k2/j.php?MTID=tb5710cac7d8b81a0e0e5c436b48545bc (https://src.webex.com/src/k2/j.php?MTID=tb5710cac7d8b81a0e0e5c436b48545bc) 2. Enter your name and email address. 3. Click "Join Now". 4. Follow the instructions that appear on your screen. 5. To receive a call back, provide your phone number when you join the session.------------------------------------------------------- To join the session by phone only ------------------------------------------------------- Call the number below and enter the access code. Toll-free number (US/Canada): 1-877-668-4490 Access code: 643 345 106 Meeting TypeWebcast Contacts Allison Hilbert, 919-941-9433, Allison.Hilbert@src.org (mailto:Allison.Hilbert@src.org)Preferred Contact Method: Email NSF Related Organizations NSF-Wide Directorate for Engineering Core Attachments Workshop Future Nanotechnology Infrastructure Support Program (http://www.nsf.gov/attachments/132127/public/Workshop_Future_Nanotechnology_Infrastructure_Support_Program.pdf)Source: NSF (http://www.nsf.gov/events/event_summ.jsp?cntn_id=132127 WT.mc_id=USNSF_13 WT.mc_ev=click)

Biodegradable, Nanoscale Thin Films Release Drugs in Steady Doses Over a Long Period of Time

National Nanomanufacturing Network - August 6, 2014 - 7:48am
About one in four older adults suffers from chronic pain. Many of those people take medication, usually as pills. But this is not an ideal way of treating pain: Patients must take medicine frequently, and can suffer side effects, since the contents of pills spread through the bloodstream to the whole body. Now researchers at MIT have refined a technique that could enable pain medication and other drugs to be released directly to specific parts of the body — and in steady doses over a period of up to 14 months. The method uses biodegradable, nanoscale “thin films” laden with drug molecules that are absorbed into the body in an incremental process. “It’s been hard to develop something that releases [medication] for more than a couple of months,” says Paula Hammond, the David H. Koch Professor in Engineering at MIT, and a co-author of a new paper on the advance. “Now we’re looking at a way of creating an extremely thin film or coating that’s very dense with a drug, and yet releases at a constant rate for very long time periods.” In the paper, published today in the Proceedings of the National Academy of Sciences, the researchers describe the method used in the new drug-delivery system, which significantly exceeds the release duration achieved by most commercial controlled-release biodegradable films. “You can potentially implant it and release the drug for more than a year without having to go in and do anything about it,” says Bryan Hsu PhD ’14, who helped develop the project as a doctoral student in Hammond’s lab. “You don’t have to go recover it. Normally to get long-term drug release, you need a reservoir or device, something that can hold back the drug. And it’s typically nondegradable. It will release slowly, but it will either sit there and you have this foreign object retained in the body, or you have to go recover it.” Layer by layer The paper was co-authored by Hsu, Myoung-Hwan Park of Shamyook University in South Korea, Samantha Hagerman ’14, and Hammond, whose lab is in the Koch Institute for Integrative Cancer Research at MIT. The research project tackles a difficult problem in localized drug delivery: Any biodegradable mechanism intended to release a drug over a long time period must be sturdy enough to limit hydrolysis, a process by which the body’s water breaks down the bonds in a drug molecule. If too much hydrolysis occurs too quickly, the drug will not remain intact for long periods in the body. Yet the drug-release mechanism needs to be designed such that a drug molecule does, in fact, decompose in steady increments. To address this, the researchers developed what they call a “layer-by-layer” technique, in which drug molecules are effectively attached to layers of thin-film coating. In this specific case, the researchers used diclofenac, a nonsteroidal anti-inflammatory drug that is often prescribed for osteoarthritis and other pain or inflammatory conditions. They then bound it to thin layers of poly-L-glutamatic acid, which consists of an amino acid the body reabsorbs, and two other organic compounds. The film can be applied onto degradable nanoparticles for injection into local sites or used to coat permanent devices, such as orthopedic implants. In tests, the research team found that the diclofenac was steadily released over 14 months. Because the effectiveness of pain medication is subjective, they evaluated the efficacy of the method by seeing how well the diclofenac blocked the activity of cyclooxygenase (COX), an enzyme central to inflammation in the body. “We found that it remains active after being released,” Hsu says, meaning that the new method does not damage the efficacy of the drug. Or, as the paper notes, the layer-by-layer method produced “substantial COX inhibition at a similar level” to pills. The method also allows the researchers to adjust the quantity of the drug being delivered, essentially by adding more layers of the ultrathin coating. A viable strategy for many drugs Hammond and Hsu note that the technique could be used for other kinds of medication; an illness such as tuberculosis, for instance, requires at least six months of drug therapy. “It’s not only viable for diclofenac,” Hsu says. “This strategy can be applied to a number of drugs.” Indeed, other researchers who have looked at the paper say the potential medical versatility of the thin-film technique is of considerable interest. "I find it really intriguing because it's broadly applicable to a lot of systems," says Kathryn Uhrich, a professor in the Department of Chemistry and Chemical Biology at Rutgers University, adding that the research is "really a nice piece of work." To be sure, in each case, researchers will have to figure out how best to bind the drug molecule in question to a biodegradable thin-film coating. The next steps for the researchers include studies to optimize these properties in different bodily environments and more tests, perhaps with medications for both chronic pain and inflammation. A major motivation for the work, Hammond notes, is “the whole idea that we might be able to design something using these kinds of approaches that could create an [easier] lifestyle” for people with chronic pain and inflammation. Hsu and Hammond were involved in all aspects of the project and wrote the paper, while Hagerman and Park helped perform the research, and Park helped analyze the data. The research described in the paper was supported by funding from the U.S. Army and the U.S. Air Force.Source: MIT News (http://newsoffice.mit.edu/2014/advanced-thin-film-technique-could-deliver-long-lasting-medication-0804)

Examining the Potential of Breakthrough Nanotechnology Opportunities

National Nanomanufacturing Network - July 31, 2014 - 4:05am
Nanotechnology-enabled products offer the potential to expand future consumer markets having significant societal and economic impact. As part of its investment in nanotechnology, the U.S. government continues an open dialogue regarding the impact and return on investment of funding provided through the National Nanotechnology Initiative (NNI) to foster fundamental science, education and training, and commercialization of nanotechnology. While the NNI investment in fundamental science has clearly positioned the U.S. as the global nanotechnology leader, commercialization of nanotechnology innovations in the U.S. has lagged behind other countries such that numerous panels of advisors and committees have called for increases or shifting of funds to foster nanomanufacturing, effective technology transfer, and commercialization of these innovations. Recently, the House Subcommittee on Commerce, Manufacturing, and Trade, chaired by Rep. Lee Terry (R-NE), part of the House Committee on Energy and Commerce, held a hearing on "Nanotechnology: Understanding How Small Solutions Drive Big Innovation." Held on July 29, 2014, subcommittee members heard from several nanotech industry leaders about the current state of nanotechnology and the direction that it is headed. With Rep. Terry’s emphasis that nanotechnology brings great opportunities to advance a broad range of industries, bolster the U.S. economy, and create new manufacturing jobs, the following response excerpts by panel members heard at the hearing provide key insights into how the U.S. may capitalize from these breakthrough opportunities. Professor Milan Mrksich of Northwestern University discussed the economic opportunities of nanotechnology, and obstacles to realizing these benefits. He commented, “Current challenges to realizing the broader economic promise of the nanotechnology industry include the development of strategies to ensure the continued investment in fundamental research, to increase the fraction of these discoveries that are translated to technology companies, to have effective regulations on nanomaterials, to efficiently process and protect intellectual property to ensure that within the global landscape, the United States remains the leader in realizing the economic benefits of the nanotechnology industry.” James Phillips, Chairman CEO at NanoMech, Inc., and a member of the NanoBusiness and Commercialization Association (NanoBCA), added, “We must capitalize immediately on our great University system, our National Labs, and tremendous agencies like the National Science Foundation, to be sure this unique and best in class innovation ecosystem, is organized in a way that promotes nanotechnology, tech transfer and commercialization in dramatic and laser focused ways so that we capture the best ideas into patents quickly, that are easily transferred into our capitalistic economy so that our nation’s best ideas and inventions are never left stranded, but instead accelerated to market at the speed of innovation so that we build good jobs and improve the quality of life and security for our citizens faster and better than any other country on our planet.” Other comments by panelists emphasized the need for nanotechnology education and training, strategies for global competitiveness, benefits of public-private partnerships to accelerate the innovation ecosystem, and challenges of retaining and transitioning foreign students into the U.S. workforce. The hearing concluded with an interesting perspective presented by Chairman Terry commenting, “Nanotech is a true science race between the nations, and we should be encouraging the transition from research breakthroughs to commercial development. I believe the U.S. should excel in this area”. For further details of the hearing and panelists commentary, the NNN recommends visiting the website link: http://energycommerce.house.gov/press-release/subcommittee-examines-breakthrough-nanotechnology-opportunities-america (http://energycommerce.house.gov/press-release/subcommittee-examines-breakthrough-nanotechnology-opportunities-america).

Nanosensor Arrays Enable Highly Sensitive Chemical Fingerprinting for Explosive Detection

National Nanomanufacturing Network - July 31, 2014 - 3:30am
Reliable detection of trace amounts of hazardous chemicals, in particular explosives, remains a pervasive problem due to the broad variety of associated chemical compounds that must be monitored in an open environment. In combination with the inherently low vapor pressures of most explosive compounds, the challenges of detecting potential threats require sensing techniques having ultra-high sensitivity, high selectivity, and rapid response. While such performance is available using sophisticated and expensive equipment, the need exists for portable, low cost systems that can discriminate a broad range of chemical species with high sensitivity and low probability of false responses. A broad range of nanomaterials have proven effective for chem/bio detection due to their high surface to volume ratio, thereby providing high sensitivity. Effective probability of detection has been demonstrated for certain trace chemical analysis by chemically functionalizing the nanomaterial surface such that the analyte of interest has an increased affinity to bind with the nanomaterial surface, which changes the electrical properties of the sensor. While this has enabled a pathway for highly sensitive, low cost sensor platforms, chemical selectivity for detection in open environments remains a challenge. For this, the concept of a chemical nose is required that can accurately discriminate trace chemicals in air. Approaches to chemical nose sensing typically include arrays of nanosensors with different elements of the array having variable properties for binding different chemical species by varying the chemical functionality added to the individual sensors in the array. Subsequent statistical analysis of the sensor array when exposed to various compounds can then provide a specific signature associated with each compound. Establishing a library of signatures makes this approach extendable for identification of a broad range of chemical unknowns. Recently, Lichtenstein, et. al. reported on the demonstration of a chemically modified nanosensor array platform for ultrasensitive detection of explosives (http://www.nature.com/ncomms/2014/140624/ncomms5195/full/ncomms5195.html) . The reported platform consisted of 144 nanosensors arranged into 8 subarrays of 18 nanosensors. Each nanosensor element consisted of a silicon nanowire Field Effect Transistor (FET) device, with each subarray chemically modified with different small molecule receptors for ultrasensitive discrimination of chemical species. Each subarray is fed by a microfluidic channel which controls the flow and interaction of the analyte with the modified sensor array. Detection occurs by first sampling the air for 5 seconds, which is pre-concentrated by flowing through a microporous filter (50-100 l/min), then flushing the adsorbed analyte from the filter membrane using a commercially available explosive standard solution, which subsequently carries the analyte to the nanosensor subarrays. Characterization of the chemical nose platform for a range of explosive compounds demonstrated unprecedented sensitivity in the parts per quadrillion (10-15) range. More importantly, the implementation of real time mathematical analysis, kinetically and thermodynamically, of the nanosensor array elements enables discrimination and identification of numerous explosive materials with standoff distance up to several meters, including non-nitrogen containing compounds. This demonstration provides a prominent example of a nano-enabled system with unprecedented performance solving a critical problem. Further development and application of surface modification chemistries and regeneration of nanosensor surfaces will impact a much broader range of applications in chemical identification and healthcare assessment. References: Lichtenstein A, Havivi E, Shacham R, Hahamy E, Leibovich R, Pevzner A, Krivitsky V, Davivi G, Presman I, Elnathan R, Engel Y, Flaxer E, Patolsky F. Supersensitive fingerprinting of explosives by chemically modified nanosensors arrays. Nat. Commun. 5(4195). doi: 10.1038/ncomms5195 (http://www.nature.com/ncomms/2014/140624/ncomms5195/full/ncomms5195.html) Image reprinted with permission from Nature Publishing Group.

JSNN nanomanufacturing group adds members

National Nanomanufacturing Network - July 30, 2014 - 3:41am
An organization established by the Joint School of Nanoscience and Nanoengineering (http://jsnn.ncat.uncg.edu/) and Gateway University Research Park (http://www.gatewayurp.com/) in Greensboro to build partnerships between academic researchers and industry has grown to 25 members in its first year, according to an update from the JSNN. The Nanomanufacturing Innovation Consortium was formed (http://www.bizjournals.com/triad/print-edition/2013/07/26/triad-companies-jsnn-join-forces-with.html?page=2) in July 2013 with an initial group of members that included RF Micro Devices (http://www.rfmd.com/), Syngenta (http://www.syngenta-us.com/home.aspx) and VF Jeanswear among others. Members pay a fee to join the NIC and in return gain access to the JSNN’s cutting-edge equipment as well as access to ideas and expertise from the school’s scientists. Other companies have joined since including (http://www.bizjournals.com/triad/blog/2013/12/itgs-cone-denim-burlington.html) International Textile Group’s (http://www.itg-global.com/) Cone Denim and Burlington divisions, Callaway Carbons, Horiba and AxNano. The 25th member of the group and the most recent to join is Luna Innovations (NASDAQ: LUNA), a Roanoke company that makes fiber optic tools for the telecommunications, aerospace, automotive, energy and defense industries. Cone Denim’s Tom Tantillo (http://www.bizjournals.com/triad/search/results?q=Tom%20Tantillo) said his company is already seeing benefits from its first few months as part of the NIC. “This is proving to be an invaluable resource to our organic growth as well as our market competitiveness,” he said. “Having access to the robust tool set and knowledge base at the JSNN gives us an unprecedented competitive edge in certifying that the technical metrics of a newly engineered product will meet consumer performance expectations.” “The development of strong industry relationships is critical to the success of the Joint School of Nanoscience and Nanoengineering,” said James Ryan (http://www.bizjournals.com/triad/search/results?q=James%20Ryan), founding dean of the school, which is a partnership of N.C. A T State University (http://www.ncat.edu/) and UNC-Greensboro (http://www.uncg.edu/). “JSNN continues to benefit from the leadership and vision of member companies, and we look forward to growing the NIC and continuing collaborations with our partners.”Source: Triad Business Journal

Researchers achieve 'holy grail' of battery design: A stable lithium anode

National Nanomanufacturing Network - July 30, 2014 - 3:31am
The development could lead to smaller, cheaper and more efficient rechargeable batteries. Engineers across the globe have been racing to design smaller, cheaper and more efficient rechargeable batteries to meet the power storage needs of everything from handheld gadgets to electric cars. In a paper (http://www.nature.com/nnano/journal/vaop/ncurrent/full/nnano.2014.152.html) published today in the journal Nature Nanotechnology, researchers at Stanford University report that they have taken a big step toward accomplishing what battery designers have been trying to do for decades – design a pure lithium anode. All batteries have three basic components: an electrolyte to provide electrons, an anode to discharge those electrons and a cathode to receive them. Today, we say we have lithium batteries, but that is only partly true. What we have are lithium ion batteries. The lithium is in the electrolyte but not in the anode. An anode of pure lithium would be a huge boost to battery efficiency. “Of all the materials that one might use in an anode, lithium has the greatest potential. Some call it the Holy Grail,” said Yi Cui (http://profiles.stanford.edu/yi-cui), a professor of Materials Science and Engineering (http://mse.stanford.edu/) and leader of the research team. “It is very lightweight, and it has the highest energy density. You get more power per volume and weight, leading to lighter, smaller batteries with more power.” But engineers have long tried and failed to reach this Holy Grail. “Lithium has major challenges that have made its use in anodes difficult. Many engineers had given up the search, but we found a way to protect the lithium from the problems that have plagued it for so long,” said Guangyuan Zheng, a doctoral candidate in Cui’s lab and first author of the paper. In addition to Cui and Zheng, the research team includes Steven Chu (http://physics.stanford.edu/people/faculty/steven-chu), the former U.S. Secretary of Energy and Nobel Laureate who recently resumed his professorship at Stanford. “In practical terms, if we can triple the energy density and simultaneously decrease the cost four-fold, that would be very exciting. We would have a cell phone with triple the battery life and an electric vehicle with a 300 mile range that cost $25,000 – and with better performance than an internal combustion engine car getting 40 mpg,” Chu said. The engineering challenge In the paper, the authors explain how they are overcoming the problems posed by lithium. Most lithium ion batteries, like those you might find in your smart phone or hybrid car, work similarly. The key components include an anode, the negative pole from which electrons flow out and into a power-hungry device, and the cathode, where the electrons re-enter the battery once they have traveled through the circuit. Separating them is an electrolyte, a solid or liquid loaded with positively charged lithium ions that travel between the anode and cathode. During charging, the positively charged lithium ions in the electrolyte are attracted to the negatively charged anode, and the lithium accumulates on the anode. Today, the anode in a lithium ion battery is actually made of graphite or silicon.Engineers would like to use lithium for the anode, but so far they have been unable to do so. That’s because the lithium ions expand as they gather on the anode during charging. All anode materials, including graphite and silicon, expand somewhat during charging, but not like lithium. Researchers say that lithium’s expansion during charging is “virtually infinite” relative to the other materials. Its expansion is also uneven, causing pits and cracks to form in the outer surface, like paint on the exterior of a balloon that is being inflated. The resulting fissures on the surface of the anode allow the precious lithium ions to escape, forming hair-like or mossy growths, called dendrites. Dendrites, in turn, short circuit the battery and shorten its life. Preventing this buildup is the first challenge of using lithium for the battery’s anode. The second engineering challenge involves finding a way to deal with the fact that lithium anodes are highly chemically reactive with the electrolyte. It uses up the electrolyte and reduces battery life. An additional problem is that the anode and electrolyte produce heat when they come into contact. Lithium batteries, including those in use today, can overheat to the point of fire, or even explosion. They are, therefore, a serious safety concern. The recent battery fires in Tesla cars and on Boeing’s Dreamliner are prominent examples of the challenges of lithium ion batteries. Building the nanospheres To solve these problems the Stanford researchers built a protective layer of interconnected carbon domes on top of their lithium anode. This layer is what the team has called nanospheres. The Stanford team’s nanosphere layer resembles a honeycomb: it creates a flexible, uniform and non-reactive film that protects the unstable lithium from the drawbacks that have made it such a challenge. The carbon nanosphere wall is just 20 nanometers thick. It would take about 5,000 layers stacked one atop another to equal the width of single human hair. “The ideal protective layer for a lithium metal anode needs to be chemically stable to protect against the chemical reactions with the electrolyte and mechanically strong to withstand the expansion of the lithium during charge,” said Cui, who is a member of the Stanford Institute for Materials and Energy Sciences at SLAC National Accelerator Laboratory. The Stanford nanosphere layer is just that. It is made of amorphous carbon, which is chemically stable, yet strong and flexible so as to move freely up and down with the lithium as it expands and contracts during the battery’s normal charge-discharge cycle. Ideal within reach In technical terms, the nanospheres improve the coulombic efficiency of the battery – a ratio of the amount of lithium that can be extracted from the anode when the battery is in use compared with the amount put in during charging. A single round of this give-and-take process is called a cycle. Generally, to be commercially viable, a battery must have a coulombic efficiency of 99.9 percent or more, ideally over as many cycles as possible. Previous anodes of unprotected lithium metal achieved approximately 96 percent efficiency, which dropped to less than 50 percent in just 100 cycles—not nearly good enough. The Stanford team’s new lithium metal anode achieves 99 percent efficiency even at 150 cycles. “The difference between 99 percent and 96 percent, in battery terms, is huge. So, while we’re not quite to that 99.9 percent threshold, where we need to be, we’re close. And this is a significant improvement over any previous design,” Cui said. “With some additional engineering and new electrolytes, we believe we can realize a practical and stable lithium metal anode that could power the next generation of rechargeable batteries.”Source: Stanford School of Engineering (https://engineering.stanford.edu/news/stanford-team-achieves-holy-grail-battery-design-stable-lithium-anode)Image reprinted with permission from Interconnected hollow carbon nanospheres for stable lithium metal anodes ; Guangyuan Zheng, Seok Woo Lee, Zheng Liang, Hyun-Wook Lee, Kai Yan, Hongbin Yao; Nature Nanotechnology 2014.

Progress Review on the Coordinated Implementation of the National Nanotechnology Initiative ...

National Nanomanufacturing Network - July 24, 2014 - 3:53am
The National Nanotechnology Coordination Office (NNCO), on behalf of the Nanoscale Science, Engineering, and Technology (NSET) Subcommittee of the Committee on Technology, National Science and Technology Council (NSTC), will hold a public webinar on Thursday, July 31, 2014 from 12 pm to 1 pm EDT. The purpose of this webinar is to provide a forum to answer questions related to the Federal Government's “Progress Review on the Coordinated Implementation of the National Nanotechnology Initiative (NNI) 2011 Environmental, Health, and Safety Research Strategy.” Discussion during the webinar will focus on the research activities undertaken by NNI agencies to advance the current state of the science as highlighted in the progress review. Representative research activities as provided in the Progress Review will be discussed in the context of the 2011 NNI EHS Research Strategy's six core research areas: Nanomaterial Measurement Infrastructure, Human Exposure Assessment, Human Health, the Environment, Risk Assessment and Risk Management Methods, and Informatics and Modeling. A moderator will identify relevant questions and pose them to the panel of NNI agency representatives during the live webinar. Due to time constraints, not all questions may be addressed. The moderator reserves the right to group similar questions and to skip questions, as appropriate. Please send your questions to webinar@nnco.nano.gov. (mailto:webinar@nnco.nano.gov%3cmailto:webinar@nnco.nano.gov) Details: Thursday, July 31, 2014, 12 pm – 1 pm EDTLog in information and event details at http://www.nano.gov/2014webinar (http://www.nano.gov/2014webinar).A public copy of the “Progress Review on the Coordinated Implementation of the National Nanotechnology Initiative 2011 Environmental, Health, and Safety Research Strategy” can be accessed at www.nano.gov/2014EHSProgressReview (http://www.nano.gov/2014EHSProgressReview). The 2011 NNI EHS Research Strategy can be accessed at www.nano.gov/node/681 (http://www.nano.gov/node/681).Source: Federal Register (https://www.federalregister.gov/articles/2014/07/22/2014-17189/national-nanotechnology-coordination-office)

Nano-sized silicon oxide electrode for the next generation lithium ion batteries

National Nanomanufacturing Network - July 17, 2014 - 3:15am
The lithium ion battery market has been growing steadily and has been seeking an approach to increase battery capacity while retaining its capacity for long recharging process. Structuring materials for electrode at the nanometre-length scale has been known to be an effective way to meet this demand; however, such nanomaterials would essentially need to be produced by high throughput processing in order to transfer these technologies to industry.This article published in the Science and Technology of Advanced Materials ("High throughput production of nanocomposite SiO x powders by plasma spray physical vapor deposition for negative electrode of lithium ion batteries" (http://dx.doi.org/doi:10.1088/1468-6996/15/2/025006)) reports an approach which potentially has an industrially compatible high throughputs to produce nano-sized composite silicon-based powders as a strong candidate for the negative electrode of the next generation high density lithium ion batteries. The authors have successfully produced nanocomposite SiO powders by plasma spray physical vapor deposition using low cost metallurgical grade powders at high throughputs. Using this method, they demonstrated an explicit improvement in the battery capacity cycle performance with these powders as electrode.The uniqueness of this processing method is that nanosized SiO composites are produced instantaneously through the evaporation and subsequent co-condensation of the powder feedstock. The approach is called plasma spray physical vapor deposition (PS-PVD). In Fig. 1, raw SiO and PS-PVD SiO composites are shown.The composites are 20 nm particles, which are composed of a crystalline Si core and SiOx shell. Furthermore, the addition of methane (CH4) promotes the reduction of SiO and results in the decreased SiO-shell thickness as shown in Fig. 2. The core-shell structure is formed in a single-step continuous processing.As a result, the irreversible capacity was effectively decreased, and half-cell batteries made of PS-PVD powders have exhibited improved initial efficiency and maintenance of capacity as high as 1000 mAhg-1 after 100 cycles at the same time.Source: National Institute for Materials Science

Carbodeon enables 20 percent increase in polymer thermal filler conductivity with 0.03 wt. ...

National Nanomanufacturing Network - July 9, 2014 - 6:58am
Vantaa, Finland – 9th July 2014: Carbodeon, a Finnish-based producer of functionalised nanodiamond materials, can now achieve a 20 percent increase in polymer thermal performance by using as little as 0.03 wt.% nanodiamond material at 45 percent thermal filler loading, enabling increased performance at a lower cost than with traditional fillers. Last October, Carbodeon published its data on thermal fillers showing that the conductivity of polyamide 66 (PA66) based thermal compound could be increased by 25 percent by replacing 0.1 wt.% of the typically maximum effective level of boron nitride filler (45 wt.%) with the company’s application fine-tuned nanodiamond material. The latest refinements in nanodiamond materials and compound manufacturing allow similar level performance improvements but with 70 percent less nanodiamond consumption and thus, greatly reduced cost. The samples were manufactured at the VTT Technical Research Centre in Finland and their thermal performance was analyzed by ESK (3M) in Germany. “The performance improvements achieved are derived from the extremely high thermal conductivity of diamond, our ability to optimise the nanodiamond filler affinity to applied polymers and other thermal fillers and finally, Carbodeon’s improvements in nanodiamond filler agglomeration control,” said Carbodeon CTO Vesa Myllymäki. “With the ability to control all these parameters, the nanotechnology key paradigm of ‘less gives more’ can truly be realised.” The active surface chemistry inherent in detonation-synthesised nanodiamonds has historically presented difficulties in utilising the potential benefits of the 4-6nm particles, making them prone to agglomeration. Carbodeon optimises this surface chemistry so that the particles are driven to disperse and to become consistently integrated throughout parent materials, especially polymers. The much-promised properties of diamond can thus be imparted to other materials with very low, and hence economic, concentrations. For more demanding requirements, conductivity increases of as much as 100 percent can be achieved using 1.5 percent nanodiamond materials at 20 percent thermal filler loadings. “This increase in thermal conductivity is achieved without affecting the electrical insulation or other mechanical properties of the material and with no or very low tool wear, making it an ideal choice for a wide range of electronics and LED applications,” said Vesa Myllymäki. “We know we have not yet uncovered all the benefits that Carbodeon nanodiamonds can deliver and continue our focused application development on both polymer thermal compounds, and on metal finishing and industrial polymer coatings,” Myllymäki added. “Recently we were granted a patent on nanodiamond-containing thermoplastic thermal composites and we see great future opportunities for these materials.” About Carbodeon Ltd Carbodeon supplies super hard materials for applications where toughness is at a premium. Its patented technologies offer superior opportunities to several fields of business. Its grades of Ultra-Dispersed Diamonds -– also known as NanoDiamonds – possess the desired properties fine-tuned for a growing number of dedicated applications. These grades are sold under the name uDiamond®. Similarly, the company’s Nicanite® graphitic carbon nitride can be converted to carbon nitride thin-film coatings with unique properties. http://www.carbodeon.com (http://www.carbodeon.com) Contact: Camille Closs +44 (0)20 8286 0654 Watch PR camille@watchpr.com (mailto:camille@watchpr.com)

Improved Method of Device Area Scale-up for SWNT/Silicon Hybrid Solar Cells Using Silver Nanowires

National Nanomanufacturing Network - July 2, 2014 - 5:57am
While research on silicon solar cells has progressed the development of all organic, inorganic, and hybrid materials systems to simultaneously address the diverse set of design criteria for optimal photovoltaic (PV) performance, incorporation of hybrid materials systems has proven to be an effective method to improve some of these issues. With crystalline silicon representing the standard for high efficiency in solar cell designs, cell cost and production capacity remain concerns for the growing emphasis on broad implementation of renewable energy strategies on a global basis, with solar PV being a leading competitor. With recent studies demonstrating that the approach incorporating p-type nano-Carbon with n-type silicon in a hybrid film approach provides excellent diode junction rectification properties, improved collection and transport efficiencies due to the enhanced conductivity of the nano-C film, and superior semiconductor barrier properties at the nano-C/silicon junction. While this has proven effective for small cell design of a few square millimeters, scaling the cell area has proven challenging due to the increase in sheet resistance (Rs) of the nano-C layer as area increases resulting in a reduction in cell efficiency. Recently, Li, et.al, from the Taylor group in the Chemical and Environmental Engineering Department at Yale University, reported on a approach to significantly improve the performance for scaling up cell area for hybrid single walled carbon nanotubes (SWNT)/Silicon solar cells. In this work, the authors utilized p-type SWNTs cast onto n-type silicon as a dense film approximately 15 nm in thickness. For small cell areas on the order of 1-2 mm2, cell performance was significantly improved in comparison to other hybrid approaches due to the low Rs of the SWNT film. For larger cell areas, the Rs increased substantially to kilo-ohm/square, resulting in decreased cell efficiency. While increasing the SWNT film thickness could potentially lower Rs, the trade-off would be a reduction in optical transparency for the film, which would still reduce cell efficiency during scale-up. Patterning of metal conductor traces over the SWNT film was considered as a means to reduce Rs, but the evaporation of metal over the SWNT film resulted in cell shorting as some of the metal penetrated the pores in the film to the silicon junction. Instead, a strategy of casting silver nanowires (AgNWs) from solution at medium densities was investigated as a means to lower Rs while maintaining reasonable optical transparency during cell area scale-up. Reported results showed that casting of the AgNW films over the SWNT film reduced Rs for the scaled cell structures, and that even with the slight increase in optical absorption with the additive bilayer film, the overall performance of the scaled cells was significantly improved in comparison to the SWNT/Silicon hybrid cell design. The cells exhibited improved fill-factors which were most predominant in enhancing the efficiency, even with slight reductions in open circuit voltage and short circuit current observed for the scaled cell areas. To further improve the optical absorption for the cell, the authors cast titania (TiO2) nanoparticles over the AgNW/SWNT surfaces to reduce reflection and increase forward scattering of incident solar radiation, resulting in a marginal improvement which was further increased via post process steps. This work has developed a solution-based approach to mitigate the total resistive power loss that typically hinders the area scale-up of hybrid nano-C/Si solar cells. A nearly twofold increase of photovoltaic efficiency is observed upon the coating of AgNWs onto SWNT/Si junctions, resulting from the significant reduction in the Rs enabled by the AgNW/SWNT bilayer. The SWNT thin film with high optical transparency and extremely small thickness also allows for the direct solution deposition of antireflective TiO2 nanoparticles. A final efficiency of >10% was realized in 49 mm2 cells, with implications for complete solution processed solar cell manufacturing and ultimately cell cost reduction. The work further illustrates the role and versatility that additive nanostructured films can contribute to performance improvements for cell area scale-up. References: Device Area Scale-Up and Improvement of SWNT/Si Solar Cells Using Silver Nanowires (http://onlinelibrary.wiley.com/doi/10.1002/aenm.201400186/pdf). Xiaokai Li, Yeonwoong Jung, Jin-Shun Huang, Tenghooi Goh, and André D. Taylor; Advanced Energy Materials 2014. DOI: 10.1002/aenm.201400186 (http://dx.doi.org/10.1002/aenm.201400186) Images reprinted with permission from John Wiley and Sons; Advanced Energy Materials; Device Area Scale-Up and Improvement of SWNT/Si Solar Cells Using Silver Nanowires; © 2014 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim; Xiaokai Li,Yeonwoong Jung,Jing-Shun Huang,Tenghooi Goh,André D. Taylor.

Researchers Develop Novel Way to Waterproof Materials by Adding Exterior Surface Grooves

National Nanomanufacturing Network - July 1, 2014 - 4:20am
Researchers from Kyoto University in Japan have developed a novel way to waterproof new functionalized materials involved in gas storage and separation by adding exterior surface grooves. Their study, published in the journal Angewandte Chemie, provides a blueprint for researchers to build similar materials involved in industrial applications, such as high performance gas separation and energy storage.

Nanotechnology Impact on Manufacturing Innovation for Next Round of Institutes

National Nanomanufacturing Network - June 26, 2014 - 8:49am
A recent Request for Information (RFI) disseminated by the Department of Defense (DoD) solicits input from Industry and Academia as part in order to better understand the state-of-the-art, needs, and potential market and economic impact for future Institutes for Manufacturing Innovation (IMIs). These institutes are consortium-based Public Private Partnerships enabling the scale-up of advanced manufacturing technologies and processes with the goal of successful transition of existing science and technology into the marketplace for both Defense and commercial applications. The IMI will be led by a not-for-profit organization and focus on one technology area. DoD is seeking responses which will assist in the selection of a technology focus area from those currently under consideration.