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News Article | April 28, 2017
Site: www.greencarcongress.com

« Technion team devises method for on-demand H2 production from water and aluminum for aviation applications | Main | Ford introduces new Intelligent Speed Limiter in Europe » Researchers at the US Naval Research Laboratory’s (NRL) Chemistry Division have demonstrated that the use of zinc formed into three-dimensional sponges for use as an anode boosts the performance of nickel–zinc alkaline cells in three areas: (i) > 90% theoretical depth of discharge (DOD ) in primary (single-use) cells; (ii) > 100 high-rate cycles at 40% DOD at lithium-ion–commensurate specific energy; and (iii) the tens of thousands of power-demanding duty cycles required for start-stop microhybrid vehicles. Joseph Parker, Jeffrey Long, and Debra Rolison from NRL’s Advanced Electrochemical Materials group are leading the effort to create an entire family of safer, water-based, zinc batteries. With 3-D Zn, the battery provides an energy content and rechargeability that rival lithium-ion batteries while avoiding the safety issues that continue to plague lithium. The research appears in the journal Science. The present energy-storage landscape continues to be dominated by lithium-ion batteries despite numerous safety incidents and obstacles, including transportation restrictions, constrained resource supply (lithium and cobalt), high cost, limited recycling infrastructure, and balance-of-plant requirements—the last of which constrains the energy density of Li-ion stacks. Despite these disadvantages, Li-ion batteries are widely used because they provide high energy density, high specific power, and long cycle life—attributes that must also be met by any alternative battery system in order to compete for market share. The family of zinc-based alkaline batteries (Zn anode versus a silver oxide, nickel oxyhydroxide, or air cathode) is expected to emerge as the front-runner to replace not only Li-ion but also leadacid and nickel–metal hydride batteries. This projection arises because Zn is globally available and inexpensive, with two-electron redox (Zn0/2+) and low polarizability that respectively confer high specific capacity and power. The long-standing limitation that has prevented implementing Zn in next-generation batteries lies in its poor rechargeability due to dendrite formation. We bypass this obstacle to cycling durability by redesigning the Zn electrode as a monolithic, porous, aperiodic architecture in which an inner core of electron-conductive metallic Zn persists even to deep levels of discharge...In primary 3D Zn–air cells, this “sponge” form factor (3D Zn) discharges >90% of the Zn, a 50% improvement over conventional powder-bed composites. When cycling Zn sponges at the demanding current densities that otherwise induce dendrite formation in alkaline electrolyte—typically greater than 10 mA cm–2—the 3D Zn restructures uniformly without generating separator-piercing dendrites. Zinc-based batteries are widely used for single-use applications, but are not considered rechargeable in practice due to their tendency to grow conductive dendrites inside the battery, which can grow long enough to cause short circuits. With the benefits of rechargeability, the 3-D Zn sponge is ready to be deployed within the entire family of Zn-based alkaline batteries across the civilian and military sectors. NRL’s work is funded by the Office of Naval Research and the Advanced Research Projects Agency-Energy.


News Article | April 28, 2017
Site: www.rdmag.com

Researchers at the U.S. Naval Research Laboratory's (NRL) Chemistry Division have developed a safer alternative to fire-prone lithium-ion batteries, which were recently banned for some applications on Navy ships and other military platforms. Joseph Parker, Jeffrey Long, and Debra Rolison from NRL's Advanced Electrochemical Materials group are leading an effort to create an entire family of safer, water-based, zinc batteries. They have demonstrated a breakthrough for nickel-zinc (Ni-Zn) batteries in which a three-dimensional (3-D) Zn "sponge" replaces the powdered zinc anode traditionally used. With 3-D Zn, the battery provides an energy content and rechargeability that rival lithium-ion batteries while avoiding the safety issues that continue to plague lithium. Their research appears in the April 28th, 2017 issue of Science, the premiere journal of the American Association for the Advancement of Science. Additional contributors to this research article include former NRL staff scientist, Christopher Chervin, National Research Council postdoctoral associate, Irina Pala, as well as industry partners Meinrad Machler and CEO of EnZinc, Inc., Michael Burz. "Our team at the NRL pioneered the architectural approach to the redesign of electrodes for next-generation energy storage," said Dr. Rolison, senior scientist and principal investigator on the project. "The 3-D sponge form factor allows us to reimagine zinc, a well-known battery material, for the 21st century." Zinc-based batteries are the go-to global battery for single-use applications, but are not considered rechargeable in practice due to their tendency to grow conductive whiskers (dendrites) inside the battery, which can grow long enough to cause short circuits. "The key to realizing rechargeable zinc-based batteries lies in controlling the behavior of the zinc during cycling," said Parker, lead author on the paper. "Electric currents are more uniformly distributed within the sponge, making it physically difficult to form dendrites." The NRL team demonstrated Ni-3-D Zn performance in three ways: extending lifetime in single-use cells; cycling cells more than 100 times at an energy content competitive with lithium-ion batteries; and cycling cells more than 50,000 times in short duty-cycles with intermittent power bursts, similar to how batteries are used in some hybrid vehicles. With the benefits of rechargeability, the 3-D Zn sponge is ready to be deployed within the entire family of Zn-based alkaline batteries across the civilian and military sectors. "We can now offer an energy-relevant alternative, from drop-in replacements for lithium-ion to new opportunities in portable and wearable power, and manned and unmanned electric vehicles," said Dr. Long, "while reducing safety hazards, easing transportation restrictions, and using earth-abundant materials."


News Article | October 28, 2016
Site: www.prweb.com

Park Systems congratulates Jean-Pierre Sauvage, James Fraser Stoddart and Bernard Feringa on being awarded the 2016 Nobel Prize in chemistry for their work on molecular machines. Their extraordinary work on molecular machines is expected to lead to the development of new nanomaterials, operating sensors, creating energy-storage mechanisms and much more. This award also highlights the need for advanced analytical tools to understand and manipulate materials at the atomic and molecular level. “Park Atomic Force Microscopes or AFMs advanced surface science and topography can observe and characterize these molecules, facilitating further discoveries in supramolecular chemistry,” comments Keibock Lee, President of Park Systems. “Park AFM uniquely excels in imaging and characterizing smart materials and nano-manipulation for various applications including nanomachines.” Sauvage, Stoddart, Feringa and other researchers have built about five dozen varieties of molecular machines including knots, switches, shuttles, rotors, pumps and chains, all at chemistry's smallest scale. Too tiny to see with naked eye, the supramolecular particles are 1,000 times less than the width of a human hair. AFM is one of the few methods available to directly visualize and manipulate these nano-objects by investigating topology and field response in flat surfaces and using specific cantilever-tip to molecule interactions. “AFM techniques based on contact and non-contact modes including scanning tunneling microscopy (STM) as well as field-responsive methods have enabled quantitative and visualized experiments to correlate with the dynamics of macromolecular and supramolecular chemistry,” commented Dr. Rigoberto Advincula, who was recently awarded a $300,000 grant from the National Science Foundation to develop methods for producing knots at an industrial level. Advincula’s research was lauded early by Noble Prize recipient Jean-Pierre Sauvage, who congratulated him saying “he looks forward to reading more papers from this group in this fascinating research field.” The researchers at Case Western will collaborate with polymer physicists, theorists, and rheologists to develop various knotted macromolecules with controlled entanglements with high yields and high molecular weight that can produce different physical and chemical properties in plastics, coatings, rubber, composites and more. ”Park AFM and users will be an important tool and community going forward in designing better analytical and characterization methods for investigating supramolecular chemistry and templating for organic molecules and nanoobjects,” commented Dr. Advincula, who is giving an upcoming webinar titled Supramolecular Chemistry, NanoMachines and AFM, hosted by Park Systems. “AFM can be used as a tool for directly visualizing supramolecular topologies with adequate surface fixation methods on atomically flat surfaces and the proper tip to nano-object interaction.” The webinar is schedule for Nov. 9 and is recommended for all researchers studying smart materials including supramolecular chemistry and nanomachines. Park Atomic Force Microscopy (AFM) state-of-the art microscopy equipment provides an important method for probing and harnessing the potential of supramolecular chemistry and other rapidly advancing nano scientific fields of study. The added value include their revolutionary and patented operating system, SmartScan, and many other advanced features such as PinPoint Nanomechanical, making it an essential tool for advanced research into interlocked molecules. To attend our webinar please register at: https://attendee.gotowebinar.com/register/8025694189710243076 Park Systems is a world-leading manufacturer of atomic force microscopy (AFM) systems with a complete range of products for researchers and industry engineers in chemistry, materials, physics, and life sciences, semiconductor, and data storage industries. Park's products are used by over a thousand organizations worldwide and provide the highest data accuracy at nanoscale resolution, superior productivity, and lowest operating cost thanks to its unique technology and innovative engineering. For its efforts to advance imaging methodologies and enhance the user experiences, Park has been awarded the Frost & Sullivan 2016 Global Enabling Technology Leadership Award. Park Systems, Inc. is headquartered in Santa Clara, California with its global manufacturing and R&D headquarters in Korea. Park’s products are sold and supported worldwide with regional headquarters in the US, Korea, Japan, and Singapore, and distribution partners throughout Europe, Asia, and the Americas. Please visit http://www.parkafm.com or email inquiry(at)parkafm(dot)com. Rigoberto Advincula is Professor at the Department of Macromolecular Science and Engineering, Case Western Reserve University in Cleveland, Ohio, USA. He is a Fellow of the American Chemical Society (ACS), Fellow of the Polymer Science and Engineering Division (ACS), Fellow of the Polymer Chemistry Division (ACS). He recently received the distinguished Herman Mark Scholar Award in 2013. He is Editor of Reactive and Functional Polymers and Associate Editor of Polymer Reviews. His group does research in polymer materials, nanocomposites, colloidal science, hybrid materials, and ultrathin films towards applications from smart coatings to biomedical devices.


« X-energy and Southern Nuclear collaborate on advanced reactor development | Main | New 100 kWh Tesla Model S hits 0-60 in 2.5 seconds; 315-mile range » A Los Alamos National Laboratory team, in collaboration with Yoong-Kee Choe at the National Institute of Advanced Industrial Science and Technology in Japan and Cy Fujimoto of Sandia National Laboratories, has discovered that fuel cells based on a new phosphate-quaternary ammonium ion-pair membrane can be operated between 80 °C and 200 °C with and without water, enhancing the fuel cells’ usability under a range of conditions. The research is published in the journal Nature Energy. These fuel cells exhibit stable performance at 80–160 ˚C with a conductivity decay rate more than three orders of magnitude lower than that of a commercial high-temperature PEM fuel cell. By increasing the operational flexibility, this class of fuel cell can simplify the requirements for heat and water management, and potentially reduce the costs associated with the existing fully functional fuel cell systems. Low-temperature PEM fuel cells that use Nafion are at present being commercialized in fuel cell vehicles, but these cells can operate only at relatively low temperatures and high hydration levels; therefore, they require humidified inlet streams and large radiators to dissipate waste heat. High-temperature PEM fuel cells that use phosphoric acid (PA)-doped polybenzimidazole (PBI) could address these issues, but these PBI-based cells are difficult to operate below 140 ˚C without suffering loss of PA. The limited operating temperature range makes them unsuitable for automotive applications, where water condensation from frequent cold start-ups and oxygen reduction reactions at the fuel cell cathode occur during normal vehicle drive cycles. Currently, two main classes of polymer-based fuel cells exist. One is the class of low-temperature fuel cells that require water for proton conduction and cannot operate above 100 °C. The other type is high-temperature fuel cells that can operate up to 180 °C without water; however, the performance degrades under water-absorbing conditions below 140 °C. The operating temperature window of a PEM fuel cell is determined by the interactions between the acid (for example, tethered sulfonic acid or free phosphoric acid) and the base moieties (for example, free water or tethered QA) in the membrane, the researchers explained. For low-temperature fuel cells, the hydrogen bonding interactions between the sulfonic acid group and water molecules in Nafion is only 15.4 kcal mol−1; this does not provide enough stability above the boiling temperature of water, leading to membrane dehydration. For high-temperature fuel cells, The intermolecular interaction energy between benzimidazole and PA is 17.4 kcal mol−1—only 4.8 kcal mol−1 greater than that between PA and one water molecule, about 12.6 kcal mol−1. Due to the relatively weak interaction, benzimidazole tends to lose PA easily with water absorption. PA-doped PBI requires a high concentration of base moieties and a high acid content to impart sufficient anhydrous conductivity. The research team found that a phosphate-quaternary ammonium ion-pair that has much stronger interaction, which allows the transport of protons effectively even under water-condensing conditions. The Los Alamos team collaborated with Fujimoto at Sandia to prepare quaternary ammonium functionalized polymers. The prototype fuel cells made from the ion-pair-coordinated membrane demonstrated excellent fuel-cell performance and durability at 80-200 °C, which is unattainable with existing fuel cell technology. The performance and durability of this new class of fuel cells could even be further improved by high-performing electrode materials, said Kim, citing an advance expected within five to ten years that is another critical step to replace current low-temperature fuel cells used in vehicle and stationary applications. Researchers on this project include Kwan-Soo Lee (Los Alamos National Laboratory, Chemistry Division), Jacob Spendelow, Yu Seung Kim (Los Alamos National Laboratory, Materials Physics and Applications Division), Yoong-Kee Choe (National Institute of Advanced Industrial Science & Technology, Japan), and Cy Fujimoto (Sandia National Laboratories). Los Alamos has been a leader in fuel-cell research since the 1970s. Fuel cell technologies can significantly benefit the nation’s energy security, the environment and economy through reduced oil consumption, greenhouse gas emissions, and air pollution. The current research work supports the Laboratory’s missions related to energy security and materials for the future.


News Article | April 11, 2016
Site: www.nrl.navy.mil

Graphene, an atomically thin sheet of carbon, has been intensively studied for the last decade to reveal exceptional mechanical, electrical, and optical properties. Recently, researchers have started to explore an even more surprising property—magnetism. Theories and experiments have suggested that either defects in graphene or chemical groups bound to graphene can cause it to exhibit magnetism; however, to date there was no way to create large-area magnetic graphene which could be easily patterned. Now, scientists from the U.S. Naval Research Laboratory (NRL) have found a simple and robust means to magnetize graphene using hydrogen. This research has been published in Advanced Materials, January 20, 2015. The NRL scientists placed the graphene on a silicon wafer and then dipped it for about a minute into cryogenic ammonia with a bit of lithium. The group had recently shown that this is a quick and gentle method to add hydrogen atoms. They now see that the added hydrogen make the surface ferromagnetic. Because this method is so effective at adding hydrogen, one has to be careful about the length of exposure. Dr. Keith Whitener, NRL's Chemistry Division, explained: "This method of hydrogenation gives us access to a much wider range of hydrogen coverage than previous methods allowed, and too much hydrogen actually destroys the magnetism." However, once made, the magnetic graphene was of exceptional quality. Dr. Paul Sheehan, NRL's Chemistry Division, noted that "I was surprised that the partially hydrogenated graphene prepared by our method was so uniform in its magnetism and apparently didn't have any magnetic grain boundaries." Interestingly, the NRL group showed that the magnetic strength could be tuned by removing hydrogen atoms with an electron beam. The impact of the electrons can break the chemical bond between the graphene and the hydrogen, removing the hydrogen from the surface. Without the hydrogen, the graphene is no longer magnetic. As a result, by carefully controlling the path of the electron beam one can write magnetic patterns into the graphene (Figure). "Since massive patterning with commercial electron beam lithography system is possible, we believe that our technique can be readily applicable for current microelectronics fabrication," says Dr. Woo-Kyung Lee, materials research scientist in the Chemistry Division at NRL and project lead. Large arrays of magnetic features were quickly made, which would be particularly useful in applications from information technology to spintronics. The questions now facing the researchers are how fine the patterning of hydrogen can be and for how long the ferromagnetism can be stable. If those questions are answered, this technique could lead to a storage medium with a single hydrogenated-carbon pair storing a single magnetic bit of data, a roughly greater than million-fold improvement over current hard drives. About the U.S. Naval Research Laboratory The U.S. Naval Research Laboratory provides the advanced scientific capabilities required to bolster our country's position of global naval leadership. The Laboratory, with a total complement of approximately 2,500 personnel, is located in southwest Washington, D.C., with other major sites at the Stennis Space Center, Miss., and Monterey, Calif. NRL has served the Navy and the nation for over 90 years and continues to advance research further than you can imagine. For more information, visit the NRL website or join the conversation on Twitter, Facebook, and YouTube.


News Article | April 11, 2016
Site: www.nrl.navy.mil

Dr. C. Michael Roland, chemist and senior scientist for soft matter physics in the Chemistry Division at the U.S. Naval Research Laboratory, has been elected a Fellow of the American Physical Society (APS). Roland is recognized by the APS for important experimental contributions and physical insight into the temperature and pressure dependence of the dynamics of polymeric systems. Roland holds a Bachelor of Science degree in chemistry from Grove City College, Pennsylvania, and a Ph.D. in chemistry from the Pennsylvania State University. Prior to coming to NRL in 1986, Roland was employed by the Firestone Central Research Laboratory in Akron, Ohio, with a focus on rubber and fiber research and development. At NRL, Roland continues his studies in the viscoelastic, mechanical and dielectric properties of materials, and most recently have employed elastomeric coatings for application in military armor. Roland was editor of Rubber Chemistry & Technology from 1991 to 1999, and has served on editorial boards including Macromolecules, Advances in Chemistry, and the American Chemical Society (ACS) Symposium Series. He has consulted for various companies, including Acushnet, Allied-Signal, Bridgestone, Fujikura Rubber, Watts Radiant, and the U.S. Department of Justice. Additionally, Roland chaired the 1999 Gordon Research Conference on Elastomers, Networks, and Gels and the 1996 International Rubber Science Hall of Fame Symposium. Author of over 390 peer-review publications, 24 book chapters, 16 patents, and the book "Viscoelastic Behavior of Rubbery Materials" (Oxford Univ. Press, 2011), Roland's publications have been cited 11,000 times, earning an H-index of 53. He has been an advisor to 21 postdoctoral researchers at NRL and has given142 lectures at conferences and workshops, including four Gordon Research Conferences talks. Roland was also the recipient of the NRL E.O. Hulburt Award (2010), the Sigma Xi Pure Science Award (2002), the NRL Edison Award (2000), the ACS Charles Goodyear Medal (2012), and is a Fellow of the Institute of Materials, Minerals, and Mining (United Kingdom). About the U.S. Naval Research Laboratory The U.S. Naval Research Laboratory provides the advanced scientific capabilities required to bolster our country's position of global naval leadership. The Laboratory, with a total complement of approximately 2,500 personnel, is located in southwest Washington, D.C., with other major sites at the Stennis Space Center, Miss., and Monterey, Calif. NRL has served the Navy and the nation for over 90 years and continues to advance research further than you can imagine. For more information, visit the NRL website or join the conversation on Twitter, Facebook, and YouTube.


Scientists at the U.S. Naval Research Laboratory (NRL) have created a new type of room-temperature tunnel device structure in which the tunnel barrier and transport channel are made of the same material, graphene. Such functionalized homoepitaxial structures provide an elegant approach for realization of graphene-based spintronic, or spin electronic, devices. The research results are reported in a paper published in the journal ACS Nano (DOI: 10.1021/acsnano.5b02795). The NRL team shows that hydrogenated graphene, a hydrogen-terminated single atomic layer of carbon atoms arranged in a two-dimensional honeycomb array, acts as a tunnel barrier on another layer of graphene for charge and spin transport. They demonstrate spin-polarized tunnel injection through the hydrogenated graphene, and lateral transport, precession and electrical detection of pure spin current in the graphene channel. The team further reports higher spin polarization values than found using more common oxide tunnel barriers, and spin transport at room temperature. In spite of nearly a decade of research on spin transport in graphene, there has been little improvement in important metrics such as the spin lifetime and spin diffusion length, and reported values remain far below those predicted by theory based on graphene's low atomic number and spin-orbit coupling. Understanding the extrinsic limiting factors and achieving the theoretically predicted values of these metrics is key for enabling the type of advanced, low-power, high performance spintronic devices envisioned beyond Moore's law. Scattering caused by tunnel barriers, which are essential for solving the conductivity mismatch problem for electrical spin injection from a ferromagnetic metal into a semiconductor, is a topic that is just now attracting attention. Uniform, pinhole/defect free tunnel barriers on graphene are not easily attained with the conventional methods that use oxides. Hydrogenation of graphene offers an alternative method to achieve a homoepitaxial tunnel barrier on graphene. In contrast with fluorination and plasma treatments, the chemical hydrogenation process developed by team member Dr. Keith Whitener provides a rapid, gentler and more stable functionalization with much higher hydrogen coverage. Moreover, recent studies, also by NRL teams, show that hydrogenated graphene could be magnetic, which could be used to control spin relaxation in the graphene. Because of its extremely low spin-orbit coupling, such control has been difficult. "These new hydrogenated graphene homoepitaxial devices solve many of the issues plaguing graphene spintronics and, with the room temperature operation and possible control with magnetic moments, offer distinct advantages over previous structures for integration with modern electronics architectures," explains Dr. Adam Friedman, lead author of the study. The NRL scientists use chemical vapor deposition to grow and then sequentially deposit a four-layer (only 4 atoms thick) graphene stack. They then hydrogenate the top few layers so that they serve as a tunnel barrier for both charge and spin injection into the lower graphene channel. They deposit ohmic (gold) and ferromagnetic permalloy (red) contacts as shown in the figure, forming a non-local spin valve structure. When the scientists apply a bias current between the left two contacts, a spin-polarized charge current tunnels from the permalloy into the graphene transport channel, generating a pure spin current that diffuses to the right. This spin current is detected as a voltage on the right permalloy contact that is proportional to the degree of spin polarization and its orientation. The vectorial character of spin (compared to the scalar character of charge) provides additional mechanisms for the control and manipulation needed for advanced information processing. The NRL team demonstrated the higher spin injection efficiency (16.5%) than most previous graphene spin devices, determined spin lifetimes with the Hanle effect, and observed only a 50% loss in spin valve signal from 10 K to room temperature (left graph). The NRL research team includes Dr. Adam Friedman, Dr. Olaf van't Erve, and Dr. Berend Jonker from the Materials Science and Technology Division, Dr. Jeremy Robinson from the Electronics Science and Technology Division, and Dr. Keith Whitener, Jr. from the Chemistry Division. About the U.S. Naval Research Laboratory The U.S. Naval Research Laboratory provides the advanced scientific capabilities required to bolster our country's position of global naval leadership. The Laboratory, with a total complement of approximately 2,500 personnel, is located in southwest Washington, D.C., with other major sites at the Stennis Space Center, Miss., and Monterey, Calif. NRL has served the Navy and the nation for over 90 years and continues to advance research further than you can imagine. For more information, visit the NRL website or join the conversation on Twitter, Facebook, and YouTube.


News Article | April 11, 2016
Site: www.nrl.navy.mil

Dr. Paul E. Sheehan, a research chemist in the Surface Chemistry Branch of the Chemistry Division at the U.S. Naval Research Laboratory (NRL), was inducted as a Fellow of the American Vacuum Society (AVS) by Dr. Steven George, 2014 AVS President, and Dr. Ellen Fisher, 2014 AVS Awards Committee Chair, at the awards ceremony during the 61st Annual AVS International Symposium and Exhibition. Sheehan was named an AVS Fellow in recognition of his exceptional contributions to the detailed understanding of sp2 carbon nanostructure properties, methods for nanoscale patterning of materials, and the basis of biological and chemical sensor performance. Sheehan has studied nanoscale phenomena and surface reactions for over two decades. He was a University Fellow at the University of North Carolina where he received a bachelor's degree in Chemistry-based Materials Science in 1993 while doing undergraduate research in the group of Prof. Royce Murray. He then studied nanomechanics at Harvard University where he received his master's degree (1995) and his doctorate (1998) in Chemical Physics under the direction of Prof. Charles Lieber. He then received a National Research Council Fellowship to pursue biosensing using magnetoelectronics at NRL under the direction of Dr. Richard Colton. In 2001, NRL hired Sheehan to pursue research focused on the use of scanning probe microscopy for the fabrication and characterization of nanostructures. In 2008, Sheehan became Head of the NRL Surface Nanoscience and Sensor Technology Section. The Section is a highly interdisciplinary team comprising about fourteen biochemists, chemists, engineers, and physicists who study nanometer scale phenomena at surfaces as well as bioelectronics for sensing and biotic/abiotic interfaces. Sheehan's current research focuses on the chemical functionalization of graphene to enhance its performance in biosensing and electronics as well as the generation of nanostructures for interfacing with biology. His research has been funded by the Navy, Air Force Office of Scientific Research, Defense Advanced Research Projects Agency, and Defense Threat Reduction Agency. The detailed exploration of the structures formed from sp2 carbon—fullerenes, carbon nanotubes, and graphene—has been a major focus of the physical sciences over the past three decades. The generation of these structures, the testing of their theoretically predicted properties, and their application have all met with substantial success. Some of Sheehan's earliest work explored the mechanical properties of carbon nanotubes and SiC nanorods, showing that the elastic modulus of the nanotubes matched the predicted (and superlative) value of ~1 TPa. This was achieved by using a scanning probe to push on nanotubes whose ends were pinned. ISI named the publication one of the top 10 papers in materials science for that decade. With the advent of graphene research, Sheehan explored the chemistry and functionalization of this fascinating material, helping to understand how new chemistries such as fluorination impacted its electronic, mechanical, and magnetic properties. Graphene's properties are quite subtle. Sheehan and co-workers recently showed that, unlike bulk graphite fluoride, fluorination of graphene was metastable and depends highly on the underlying substrate. He had previously explored this theme of graphene's interaction with its substrate in showing that electronic conduction in graphene on SiC is in fact anisotropic due to charge scattering by the underlying step edges. They subsequently published a series of papers exploring the changes in conduction in graphene due to functionalization, most recently showing that electronic conductivity in graphene can be completely eliminated by hydrogenation and then completely restored to its pristine state by simple heating. The manipulation of matter at the nanoscale has been a dominant theme in Sheehan's career. He has written several reviews on nanolithography as well as developed several advances in scanning probe techniques to modify locally both soft and hard materials. He made significant contributions to the understanding of the mode of patterning of Dip Pen Nanolithography (DPN), where material deposits from an AFM tip onto a substrate. He showed that a water meniscus was not needed to transfer molecules from the tip to the surface as previously thought, and offered a detailed model of the mass transfer processes occurring in the system. Based on the insights gained from that effort, he went on to develop a variant of DPN called thermal DPN where a heated scanning probe controlled the flow of a molecule by varying its viscosity. More recently, he has focused on using the heat scanning probes to pattern graphene into functional devices. This could mean either using thermal DPN to write thin polymer masks for subsequent processing or by creating molecular templates. A more fundamental insight was that the heatable scanning probes could control local temperature with nanometer resolution and so induce reactions at that length scale. This led to the highly local removal of oxygen from graphene oxide to form thin nanoribbons of conducting graphene. Beyond the manipulation of matter at the nanoscale, Sheehan has had an ongoing interest in the physical phenomena undergirding sensor performance. Upon arriving at NRL, he pursued a novel approach to biodetection where a magnetic bead would be bound to a giant magnetoresistive (GMR) sensor if a target biomolecule such as DNA was present. The benefit of this approach is that magnetic interference is relatively rare in biological systems and the giant response by the GMR sensor to the presence of the magnetic bead makes this a highly sensitive and selective approach. Indeed, it remains one of the most effective means of directly detecting low concentrations of biomolecules. Work on the microfabricated sensors stimulated his interest in the effect of scaling sensor size. In 2005, he published a simple paper on the scaling of biosensors to the nanoscale, a popular undertaking at the time. The upshot was that, for many applications, mass transport made this an unwise choice. Others used the results to point out that many reported results were in fact impossible. His interest in sensing extended to biological approaches to sensing where he modeled how magnetotactic bacteria know how to swim north. With his developing interest in graphene nanostructures, he set out to understand how to use this new material to build inexpensive yet sensitive detectors for both chemical and biological agents. The fundamental insight was that graphene oxide, a very inexpensive derivative of graphene, could be readily and cheaply formed into sensors that had lower electronic noise and greater amenability to chemical functionalization than the carbon nanotube networks used to date. Efforts to fully utilize and understand these new materials continue to this day. His research has garnered other recognition and accolades too. His nanofabrication work has been widely reported in the general science and popular press, including in the New York Times, CBS's SmartPlanet, C&EN, and TV Globo Brazil. His nanofabrication work was selected as a Department of Defense R&D accomplishment in Defense Nanotechnology Research and Development Programs. One of his biosensor papers was cited as the Most Outstanding Contribution out of >1000 submissions to the Biosensors 2008 conference, the leading conference in the biosensors community. It too was highlighted in the popular press in the Economist and on National Public Radio (NPR). In 2009, Sheehan and his co-inventors received the NRL Edison Patent award for their patent on Thermal Dip Pen Nanolithography. Sheehan also has received three Alan Berman Research Publication Awards in his 13 years as a federal employee. About the U.S. Naval Research Laboratory The U.S. Naval Research Laboratory provides the advanced scientific capabilities required to bolster our country's position of global naval leadership. The Laboratory, with a total complement of approximately 2,500 personnel, is located in southwest Washington, D.C., with other major sites at the Stennis Space Center, Miss., and Monterey, Calif. NRL has served the Navy and the nation for over 90 years and continues to advance research further than you can imagine. For more information, visit the NRL website or join the conversation on Twitter, Facebook, and YouTube.


News Article | April 11, 2016
Site: www.nrl.navy.mil

The U.S. Naval Research Laboratory's (NRL's) Dr. John N. Russell, Jr., head of the Surface Chemistry Branch of the Chemistry Division, was honored at the annual American Vacuum Society (AVS) awards ceremony with the top Societal honor, AVS Honorary Membership. Russell was recognized for his "outstanding scientific contributions and service to the Society." The award was a complete surprise to Russell. He attended the ceremony to witness the AVS Fellow induction of Dr. Paul Sheehan, whom he nominated. As the awards ceremony drew to an end, all of the present honorary members were asked to stand and be recognized. Then it was announced that someone would receive the Honorary Membership Award. The award is given irregularly, so there is never a guarantee that anyone will be so recognized at the ceremony. The Honorary Membership Award consists of a plaque and lifetime AVS membership without dues, and free registration for the annual AVS International Symposium and Exhibition for the rest of the honorary member's life. Dr. Richard Colton, former superintendent of NRL's Chemistry Division, nominated Russell for the award. Until it was revealed at the awards ceremony, only the awards committee, the AVS board of directors, a few AVS staff, and Dr. Barry Spargo, acting superintendent of NRL's Chemistry Division, knew about the award, that is until he conscripted Dr. Kathy Wahl, head of the Molecular Interfaces and Tribology Section, and Russell's wife, Kathleen Russell, to ensure Russell attended the AVS awards ceremony. It is AVS custom to announce a new honorary member through a slow reveal introduction. Using photographs from the awardee's childhood to the present, the details about the life and accomplishments of the awardee are presented to the audience. Russell said, "Once I saw the first childhood picture, I knew they were honoring me. I had to quickly think about what I would say when they called me to the stage. But, I was in such a daze that I was uncharacteristically without words. When I returned to my seat, my wife was sitting in my chair. I did not know she was at the ceremony. She deserves the recognition as much as me. I also am very fortunate that NRL has been very supportive of my endeavors on behalf of the greater scientific community. " A member society of the American Institute of Physics, the American Vacuum Society is an interdisciplinary scientific professional society that fosters an international community of scientists, engineers, and instrument manufacturers, who strive to promote research and communicate knowledge in the important areas of surface, interface, vacuum, and thin film science/technology for the advancement of humankind. As Head of NRL's Surface Chemistry Branch, Russell directs a highly interdisciplinary research program in surface chemistry and physics in support of current and future Navy technologies. The major research topics of the branch encompass a broad scope of fundamental to applied surface problems. They range from 3-D nanoarchitectural materials for energy storage, to lubrication and low-wear coatings, to surface (bio)adhesion, to chemical vapor deposition of electronic materials, to nanomanufacturing of devices and chemical/biological sensors. Russell's research at NRL initially focused on identifying and measuring fundamental surface reaction processes important for the chemical vapor deposition of wide band-gap electronic materials such as diamond and aluminum nitride, and then the surface functionalization of hybrid organic/semiconductor materials for sensor and electronic devices. Presently he and his collaborators are examining the biodegradation chemistry of polymer coatings and surfaces. Russell earned a bachelor's degree (cum laude) in Chemistry in 1981 from Dickinson College, and his doctorate in Physical Chemistry in 1987 from the University of Pittsburgh. After a Postdoctoral Fellowship at the Corporate Research Laboratory of Exxon Research and Engineering Company, he joined the NRL research staff in 1989. In 1999 he became the Head of the Functional Materials Section and since 2005 he has been the Head of the Surface Chemistry Branch. Russell has authored more than 50 peer-reviewed scientific research papers, which have been cited more than 3,300 times. He holds one U.S. patent. Russell has given numerous invited and plenary presentations about his research at universities, and international conferences. In 2013 he began a part-time detail at the Chemical and Biological Defense Department of the Defense Threat Reduction Agency where he is engaged in developing surface science programs within the chemical defense research portfolio. Russell has served in numerous leadership roles in the American Vacuum Society, which have included President (2008), member of the Board of Directors (2003-2005; 2007-2009), AVS Symposium and Exhibition Chair (2007), AVS Surface Science Division Chair (2006), and AVS Awards Trustee (2011-13, Chair 2013). He has significantly shaped and influenced the operations of the AVS. As AVS President he led a reorganization of the Society's governing structure, which was codified in changes to the Constitution and By-Laws of the Society. He also was instrumental in many changes to the policy and procedures of the Society. During his Presidency, the Society moved from rented to owned office space in lower Manhattan. He engaged in a review of the Society's research journals, which resulted in new policies for editor reviews, journal operations, and editorial directions. He also instituted a chair succession plan for the International Symposium, which still is the practice. As Awards Committee Chair, he completely revamped the awards selection process, even redesigning the physical awards that are presented to awardees. As Professor Joseph Greene, University of Illinois and Secretary of the AVS Board of Directors noted after the ceremony, "There are very few things that the AVS does today that were not initiated by John Russell." Russell also has held leadership positions in the American Chemical Society (ACS), including member and Chair of the ACS Joint-Board Council Committee on Publications (2005-13; Chair 2008-10), member of the ACS Colloid and Surface Chemistry Division Executive Committee (2000-16), and Chair/member of several special ACS taskforces and committees. Russell has been an elected representative to the ACS Council, the legislative body of the American Chemical Society (2004-09; 2011-13), and currently serves as an Alternate Councilor (2014-16). He also was a member of the editorial boards of the Encyclopedia of Colloid and Surface Chemistry (2004-present), and Chemical and Engineering News (2008-13; Chair 2008-10). He received the NRL Chemistry Division Young Investigator Award (1992), and the NRL Berman Research Publication Award (1997). In 2008 he was inducted into the Berwick (PA) Area High School Academic Hall of Fame. In honor of his research accomplishments and scientific leadership, Russell has been elected a Fellow of both the American Vacuum Society (2006) and the American Chemical Society (2010). About the U.S. Naval Research Laboratory The U.S. Naval Research Laboratory provides the advanced scientific capabilities required to bolster our country's position of global naval leadership. The Laboratory, with a total complement of approximately 2,500 personnel, is located in southwest Washington, D.C., with other major sites at the Stennis Space Center, Miss., and Monterey, Calif. NRL has served the Navy and the nation for over 90 years and continues to advance research further than you can imagine. For more information, visit the NRL website or join the conversation on Twitter, Facebook, and YouTube.


Home > Press > Tomoyasu Mani Wins 2016 Blavatnik Regional Award for Young Scientists: Award recognizes his work at Brookhaven Lab to understand the physical processes occurring in organic materials used to harness solar energy Abstract: Tomoyasu Mani, former Goldhaber Fellow at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory and now an assistant professor in the University of Connecticut's Department of Chemistry, has received the 2016 Blavatnik Regional Award for Young Scientists in the chemistry category. The awards, established in 2007 by the Blavatnik Family Foundation in partnership with the New York Academy of Sciences, celebrate the innovative achievements of postdoctoral scientists 42 years of age or younger who work in New York, New Jersey, or Connecticut. Mani is being recognized for his "advances in the understanding of electron transport occurring in organic photovoltaics used in solar energy capture and conversion." "I'm very honored to be recognized by the Blavatnik Regional Award. As an early-career scientist, I appreciate the increased visibility in the field of chemistry and the larger scientific community that this award will bring me, and I look forward to continuing to make contributions to the field," said Mani. "Although younger generations of scientists may be unfamiliar with radiation chemistry or find it hard to apply to their work, my research to understand fundamental processes in organic solar cells is a good example of how radiation chemistry can provide us with valuable information that is hard or impossible to come by using other means." Mani joined the Chemistry Department at Brookhaven Lab in 2013. The following year, he was awarded the prestigious Gertrude and Maurice Goldhaber Distinguished Fellowship, which is given to exceptionally talented candidates who have a strong desire for independent research at the frontiers of their fields. He held this appointment until August 2016, when he became part of the Department of Chemistry faculty at the University of Connecticut. While at Brookhaven, Mani studied how delocalized electrons move through chains of organic molecules with alternating double and single bonds. Organic photovoltaic devices use these "conjugated" molecules to convert sunlight into electricity. While organic solar cells are more flexible and lightweight than the conventional silicon-based versions, their power-conversion efficiency has been limited. Understanding how the electrical charges generated by sunlight are separated and transported to produce a current is critical to increasing this efficiency. "The challenge is to characterize these charged species in the non-polar environments where the electricity-producing chemical reactions occur. We are trying to elucidate the basic principles that govern the nature of charges on a very fundamental level in such an environment," said Mani. To investigate the nature of charges in conjugated molecules, Mani combined chemical synthesis (to make the molecules), pulse radiolysis (to inject charges into the molecules), infrared spectroscopy (to study the atomic vibrations of these charged molecules), and theoretical analysis (to understand how the electrons move). His research demonstrated that molecular vibrations provide insights into the nature of charged species that can help scientists design better molecules and materials for harnessing and storing solar energy. "For someone only a few years out of graduate school, Tomo has made impressive accomplishments," said John Miller, leader of Brookhaven's Electron- and Photo-Induced Processes Group and Mani's former advisor. "He came up with several innovative ideas and designed and carried out experiments to test these ideas, often using sophisticated equipment such as accelerators and performing complex theoretical computations. Creativity, initiative, and enthusiasm are important characteristics of a young scientist, and Tomo has them all." A distinguished jury of senior scientists and engineers selected Mani from among 125 nominations submitted by 24 academic and research institutions in the New York tri-state area. One winner and two finalists were selected in each of the three award categories: life sciences, physical sciences and engineering, and chemistry. Winners each receive $30,000; finalists receive $10,000. "Tomo asked important science questions and was creative in designing new molecules to test his ideas, adept in chemical synthesis, astute in using the unique capabilities of the division's Accelerator Center for Energy Research, and insightful in his collaborations to understand how his results could give new meaning to molecular charge dynamics," said Alex Harris, chair of the Chemistry Division at Brookhaven. "We expect more great work will come from him, and we look forward to continuing our collaboration with him while he is at the University of Connecticut." This fall, Mani is teaching a course on advanced physical chemistry and leading a new research group that seeks to understand how to control electronic excited states, charge and energy transfer reactions, and spin dynamics in molecules and molecular assemblies. For his research, he continues to combine various approaches, including chemical synthesis, photo- and radiation-chemistry experimental techniques, and theoretical and computational analysis. Part of his computational work will involve the use of the computer cluster at the Center for Functional Nanomaterials, a DOE Office of Science User Facility at Brookhaven Lab. Mani will be back at Brookhaven from October 10 through 14 to discuss his research at the 2016 International Conference on Ionizing Processes. Mani regularly presents his work at conferences and is invited to talk at institutes throughout the United States and abroad. For the past five years, he has been mentoring undergraduate and graduate students. His professional memberships include the American Chemical Society, the American Association for the Advancement of Science, and the Japanese Photochemistry Association. He earned a BS in biochemistry from the University of Texas at Dallas in 2009 and a PhD in biochemistry and molecular biophysics at the University of Pennsylvania in 2013. Mani, the other two regional award winners, and the six regional finalists will be honored at a ceremony during the New York Academy of Sciences Annual Gala on November 7, 2016 in New York City. About Brookhaven National Laboratory. Brookhaven National Laboratory is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov. For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

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