http://science.energy.gov/bes/highlights/The Office of Science is the single largest supporter of basic research in the physical sciences in the United States, providing more than 40 percent of total funding for this vital area of national importance. It oversees - and is the principal federal funding agency of - the Nation's research programs in high-energy physics, nuclear physics, and fusion energy sciences.en{4673AA52-623D-4AD3-BBE9-575343C4AFE6}http://science.energy.gov/bes/highlights/2013/bes-2013-03-a/<img src='/~/media/67D8BB68CBE74D68AF860806000AC9CF.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>When it comes to stressing a crystal during irradiation, not all atoms are created equal.Tue, 11 Jun 2013 14:31:08 -0400<p>Materials used in nuclear energy reactors are bombarded by energetic particles that are inherent in generation of electricity with nuclear power.&nbsp; Additionally, these components are often under a mechanical load or &ldquo;stress&rdquo;.&nbsp; Irradiation by these energetic particles displaces atoms in the crystalline structure of the material and, in conjunction with the stress, causes the materials to slowly deform (&ldquo;creep&rdquo;), resulting in changes to the material&rsquo;s dimensions and strength.&nbsp; A new mechanism for irradiation-enhanced creep has been identified in nanocrystalline materials. The mechanism is based on nanoscale flow of the atoms in the boundaries between the nanocrystals making up the material.&nbsp; The deformation is due to local atomic relaxations within the grain boundaries as they absorb point defects e.g., interstitials and vacancies, produced in the grain interior during irradiation. The process was modeled by inserting point defects into the grain boundaries and following the material&rsquo;s subsequent response using molecular dynamics simulation as stress was applied to the system. The calculated strain rates of the material are found to be in good agreement with those experimentally measured in dilute nanocrystalline copper-tungsten alloys. Extrapolation of the calculations to vanishingly small grain sizes yields creep rates that agree very well with those found in amorphous materials, suggesting that under irradiation grain boundaries in nanocrystalline materials behave very much like an amorphous phase.</p>{4DABE467-3780-4FDA-88D2-7B004B0ECE96}http://science.energy.gov/bes/highlights/2013/bes-2013-02-a/<img src='/~/media/C7B16C93B72C4DA895FFCD6323806573.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Exploiting the self-organizing nature of atoms to block heat transfer and improve thermal-to-electrical energy conversion.Fri, 10 May 2013 11:13:34 -0400<p>Like a coach in sports, making the right substitution can make the difference between winning and losing. Using a combination of theory and simulations, the researchers at the University of Michigan EFRC predicted that replacing some of the antimony (Sb) atoms in the skutterudite mineral, cobalt antimonide (CoSb₃), would disrupt the atomic vibrations that play a crucial role in transferring heat through the material &ndash; but only if the replacement atoms took up specific atomic locations in the crystal structure. Quantum mechanical calculations were used to predict that entire 4-member rings of Sb atoms (Sb4) would be replaced by cross-diagonal rings of Ge₂Te₂ due to the natural, atomic ordering tendencies of alloying elements. The consequences of this substitution order on the atomic vibrations responsible for heat transfer was verified by molecular dynamic simulations and then experimentally demonstrated by measuring the reduction in the thermal conductivity for the substituted material CoSb_3(1-x)Ge_1.5xTe_1.5x. This approach and resulting insights can be extended to other families of thermoelectric materials to reduce the thermal conductivity of these materials and increase the efficiency of heat-to-electricity conversion for thermoelectric devices.</p>{C0AB145B-3B67-4B29-987A-C745A176A198}http://science.energy.gov/bes/highlights/2013/bes-2013-02-b/<img src='/~/media/DCE164BCA2684EA89EDA0C6A53141472.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Nano-porous metal oxide coatings on carbon fiber dramatically enhance the electrical storage capacity for supercapacitors.Fri, 10 May 2013 11:13:35 -0400<p>Pseudocapacitors are supercapacitors that store electrical charge both like a capacitor (with the normal electrostatic double layer of charges at the electrode-electrolyte interface) and like a battery (with multiple chemical reaction mechanisms involving charge transport across the electrode-electrolyte interface).&nbsp; Metal oxides such as cobalt or manganese oxide (C_o3O4 or MnO₂) store pseudocapacitive charge via metal ions which change oxidation state (e.g., Mn⁺³ <span style="line-height: 115%; font-family: symbol; color: #363636; font-size: 10pt;">&Ucirc;</span> Mn⁺⁴) as a result of the charge transfer.&nbsp;Researchers at the Energy Frontier Research Center on Heterogeneous Functional Materials, the &ldquo;HeteroFoaM Center,&rdquo; have discovered how the relative sizes, shapes, atomic arrangements and interfaces of the materials in psuedocapacitors control the amount of charge that can be stored and even the mechanisms of charge storage.&nbsp;In fact, the electrochemical storage properties are not limited by the properties of the materials and can be radically different if the &ldquo;heterogeneity&rdquo; of the composite material is understood and optimized. For example, as-deposited MnO₂ on conductive carbon fiber showed high specific capacitance (333 F/g) due to psuedocapacitance of the manganese ions, but conversion of the material through heat treatment to a different heterogeneous arrangement &ndash; a mixed-valence, nano-porous MnOx coating &ndash; dramatically enhanced storage capacity, achieving very high specific capacitance (~2,500 F/g) while maintaining excellent power density (~98 kW/kg at ~122.7 A/g).</p>{A1F1F429-A46A-4970-9BC3-853158E1144B}http://science.energy.gov/bes/highlights/2013/bes-2013-02-c/<img src='/~/media/214E9D85FBC64973AC4D23F2E487EF31.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Charge-discharge chemistry for lithium ion batteries elucidated by theoretical calculations.Fri, 10 May 2013 11:13:35 -0400<p>Ethylene carbonate (EC) electrolytes and manganese spinel (Li_xMn₂O₄) positive electrodes are commonly used in lithium ion batteries.&nbsp;A comparison of the electrochemical potentials of EC and bulk Li_xMn₂O₄ suggests that decomposition of the electrolyte would not occur directly by electrons being transferred from EC to the electrode material, but the surface of a solid can have very different properties than its interior bulk.&nbsp;Researchers at Sandia National Laboratories, as part of the Nanostructures for Electrical Energy Storage (NEES) EFRC, have completed detailed coupled simulations of the molecules of the electrolyte and the surface of the positive electrode showing that the oxygen atoms on a Li_0.6Mn₂O₄ surface can deform and weakly bind the EC molecule when it is near the electrode surface. This initial interaction does not involve the transfer of electrons (i.e., oxidation) but does enable breaking of the carbon-oxygen bond and subsequent molecular rearrangements that result in two electrons and a proton being transferred to the electrode surface.&nbsp; Therefore, a predicted series of five steps breaks down the electrolyte molecule, leaving the oxidized EC fragment still bound to the now acidified electrode surface.&nbsp; Acidification of positive electrodes is widely believed to initiate corrosion of the electrode surface and possible dissolution of manganese atoms.&nbsp;The proposed acidification mechanism&nbsp;illustrates the importance of modeling the electrolyte and the electrode surface together.</p>{C6029213-9182-4952-B478-6CF336036F65}http://science.energy.gov/bes/highlights/2013/bes-2013-02-d/<img src='/~/media/8E64780517404923909574AF5FA3CDB3.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>First observation of key intermediate state in the conversion of one photon to two electrons.Fri, 10 May 2013 11:13:36 -0400<p>Multiple exciton generation (MEG) refers to the creation of two or more pairs of charge carriers (electron-hole pairs known as excitons) from the absorption of one photon. Although MEG holds great promise for improving the efficiency of organic solar cells, it has proven challenging to implement.&nbsp;Using a model system based on either pentacene or tetracene molecules deposited upon carbon fullerene bilayers, EFRC scientists have used femtosecond electron spectroscopy to directly observe a new multiexciton (ME) state ensuing from the absorption of a single photon in the molecular layer.&nbsp;Data for both systems indicate that the ME state can decay into two separate excitons and that one electron can be transferred into the fullerene layer from each exciton.&nbsp;For pentacene, two electrons can be directly transferred from the ME state to an adjacent fullerene layer on a sub-picosecond time scale, which is much faster than electron transfer from either of the two separate excitons from ME decay. In this mechanism, losses in photovoltaic efficiency due to unproductive decay or recombination of individual excitons can be avoided by directly extracting multiple electrons from the ME state at the fullerene surface.&nbsp;Investigation of these processes has generated a new set of design principles for harvesting energy through multiple exciton generation in molecular systems.</p>{05856B6A-AE72-474E-953F-A3832973C074}http://science.energy.gov/bes/highlights/2013/bes-2013-02-e/<img src='/~/media/330C7EBF533F46ACA50A13DC4DBE1D72.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Observation of wavelike heat conduction reveals new possibilities for tailoring thermal transport through wave effects.Fri, 10 May 2013 11:13:36 -0400<p>In many materials, thermal energy is transported by vibrations of the atomic lattice known as phonons. Similar to photons of light, these lattice vibrations can be treated as waves, but in most materials the phases of the phonon waves quickly randomize after interacting among themselves, with any imperfection or with any interface between two materials. This phase randomization means that the transport of heat becomes incoherent and difficult to predict or control. In this study, heat transport through superlattices (SL) made up of periodic stacks of semiconductor thin films was studied both experimentally and theoretically with a surprising result.&nbsp;A novel experimental approach indicated that the wave properties of some heat-carrying phonons &ndash; and their coherence &ndash; could be maintained even with the presence of several material interfaces. Theoretical studies supported the experimental conclusions that the low frequency phonons traveled through the SL stack in coherent fashion as if the layered structure was a homogeneous material. This scientific discovery and modeling capability opens new pathways for controlling heat transfer through materials by tailoring the lattice waves at the nanostructure scale.</p>{CC5E4742-DF44-4DE6-81C6-9B13F34F934D}http://science.energy.gov/bes/highlights/2013/bes-2013-02-f/<img src='/~/media/6A01C553C7E6497CAE38D1EB10E262AB.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Ordered arrays of functional proteins with designed molecular properties created through self-assembly by combining proteins and synthetic polymers.Tue, 11 Jun 2013 14:31:08 -0400<p>If functional proteins could be organized into nanostructured arrays such as cylinders (one dimensional), lamellae (2 dimensional) and other three dimensional architectures, it could usher in new class of materials with unprecedented higher or even new functionality. Towards achieving this goal, scientists at the Massachusetts Institute of Technology designed a set of block copolymers consisting of proteins covalently bonded with synthetic polymers and explored their solution phase behavior as a function of polymer molecular weight, block copolymer composition, concentration, and temperature in the high concentration regime. The incompatibility between the protein and polymer and their chemical interaction with the solvent (water in this case) leads to novel self-assembly properties that can be controlled with the rational design of the block copolymers. &nbsp;Neutron scattering experiments show that water distribution within the nanostructures drives transitions between ordered phases. Since proteins have incipient aggregating tendency in solutions, especially at higher concentrations, new routes are needed to exploit their unique function. The ability to organize functional biomaterials at high concentrations without aggregation through the block copolymer route offers new ways for the rational design of novel materials for potential applications in catalysis, sensors, nanotechnology and renewable energy.</p>{F2744DB8-8FA0-490B-A031-44FEEA748952}http://science.energy.gov/bes/highlights/2013/bes-2013-01-a/<img src='/~/media/1F6D9519A1064CCAA7E18958908C5C00.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>New computational technique creates high resolution maps of subsurface CO₂ after geologic sequestration.Fri, 10 May 2013 11:13:34 -0400<p>A powerful new &ldquo;seismic inversion&rdquo; technique&nbsp;&nbsp;uses time-lapse seismic data to make high resolution images useful for evaluating subsurface migration of CO₂ following geologic sequestration. Migration of CO₂ alters the mechanical properties of porous rocks which can be monitored from high frequency rock property variations embedded in the seismic amplitude data. The technique utilizes a dictionary of seismic &ldquo;wavelets&rdquo;, information derived from seismic data before CO₂ injection, and an optimization algorithm to identify the set of common wavelets that best describe the variations in seismic amplitudes observed pre- and post- CO₂ injection. The University of Texas-Austin team applied it to investigate the migration pathways of the CO₂ plume at the Cranfield, Mississippi field demonstration site where such time-lapse surface seismic surveys are available. The raw seismic data showed only a weak signature of CO₂ injection. However, &ldquo;seismic inversion&rdquo; of the data enhanced the information content, showing that the injected CO₂ migrated mostly along the top of the layer of rock into which it was injected, but there was no leakage through the reservoir seals. This technique affords an effective way to monitor potential leakage of CO₂ plumes at various reservoirs.</p>{6F0B919E-1B0C-405A-9197-3EE38C142729}http://science.energy.gov/bes/highlights/2013/bes-2013-01-b/<img src='/~/media/373F5820C3A547A88B883700AA5E9AD9.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>New porous, electrically conductive materials have potential uses in full cells, batteries, and solar photovoltaics.Tue, 11 Jun 2013 14:31:07 -0400<p>Metal&minus;organic frameworks (MOFs) are microporous materials made up at the molecular level of a lattice of metal ion and organic molecule building blocks. With very high intrinsic porosity and surface area, these materials have been developed for applications in gas separation and storage.&nbsp; Yet their very low electrical conductivity drastically impairs their utility as high surface area conductors in energy applications such as batteries, fuel cells, supercapacitors, or photovoltaics - the electrically inactive organic ligands normally do not provide a good electrical pathway.&nbsp; In a collaboration between MIT and Osaka University, researchers have for the first time synthesized a MOF that shows both stable micropores and good charge mobility.&nbsp; The key to the breakthrough was to use an organic molecule, tetrathiafulvalene (TTF), well known for contributing to electrical conductivity in charge transfer salts by forming stacked molecular columns.&nbsp; In the new TTF-based MOF material, a less-than-ideal TTF stacking sequence nevertheless displayed a high charge mobility, comparable to polythiophene materials widely used in organic photovoltaic devices.&nbsp; If the stacking overlap between neighboring TTF molecules can be improved, MOFs with even higher charge mobility may be possible.</p>{B56456B2-94E2-452C-9693-7B23DEBF1F27}http://science.energy.gov/bes/highlights/2013/bes-2013-01-c/<img src='/~/media/A058B1346BE74749B7309FB5D8AE5031.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Atomic-Scale, femtosecond time-scale measurements unravel the atomistic pathways and speed limits for copper migration through a nanocrystal.Tue, 11 Jun 2013 14:31:07 -0400<p>Ultrafast x-ray scattering and spectroscopic measurements have been used to probe the phase transition of a type of binary nanocrystal where one atomic element becomes mobile (like a liquid) and the other elemental species remains in a crystalline lattice.&nbsp;The crystal class (specifically Cu₂S or copper sulfide in this particular case) is called "superionic" because the copper (Cu) ionic sub-lattice "melts" allowing the Cu atoms to move more freely while the sulfur (S) sub-lattice maintains the solid crystalline container. The research confirmed the supposition that it does not take much Cu movement to disorder the Cu sub-lattice, while expanding the interatomic distances between the S atoms and making the S lattice more symmetric.&nbsp;The key finding is that the phase transition occurs on the time scale of a single "hopping event," defined as the time needed for Cu to move from one local sweet spot to another.&nbsp;This insight is useful because ion transport is a key aspect of battery function and because ionic phase transition materials can be used in electrochemical switching devices.</p>{14FF3A14-5038-402A-B3D7-320BA7EEA712}http://science.energy.gov/bes/highlights/2012/bes-2012-12-a/<img src='/~/media/bes/images/highlights/2012/12/lee-mit-thumb.jpg' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>This observation paves the way for a deeper understanding of high-temperature superconductivity and future applications for quantum computing.Thu, 02 May 2013 16:32:14 -0400 <p>Confirming earlier theoretical predictions, a hallmark signature of a new kind of magnetic behavior, called the &quot;quantum spin liquid&quot; (QSL), has been observed. Unlike normal magnets wherein the electron spins freeze into an ordered state below a threshold temperature, in a QSL the electron spins associated with the material's magnetism continue to have motion even at absolute zero temperature. Through characterization by inelastic neutron scattering on large high-quality, single-crystal samples of the mineral ZnCu3(OD)6Cl2, the team, led by the Massachusetts Institute of Technology, discovered that the scattered neutrons have a broad spread of energies, a fundamental signature predicted by theory for a QSL. In normal magnets the scattered neutrons will have similar energy and produce “spots” rather than the diffuse intensity. The QSL can be thought of as the third fundamental state of magnetism; the first two states being the ferromagnet (all spins aligned parallel, as in a compass needle) and antiferromagnet (adjacent spins point in opposite directions, as in hard drive read heads). Research on QSL systems can lead to a deeper understanding of high temperature superconductivity and to potential applications in quantum information for future computers.</p> {4F6D157B-62D3-4F1D-9FE8-CDF05730AE81}http://science.energy.gov/bes/highlights/2012/bes-2012-12-b/<img src='/~/media/5A9D9A8DF1DF45FE8F45A41AC6B245E6.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>A simple, robust catalyst is capable of both water oxidation and carbon dioxide splitting, two difficult yet key reactions for solar energy conversion.Fri, 10 May 2013 11:21:36 -0400<p>In the field of artificial photosynthesis, solar fuels, generated by splitting water into hydrogen and oxygen or reducing carbon dioxide to carbon monoxide, methanol, or hydrocarbons, have great potential as alternative energy sources.&nbsp; Such fuels could further solve an energy storage problem by allowing solar energy collected during the day to be stored and used at night.&nbsp; A key challenge for solar fuel production is finding enough energy from sunlight to drive the complex water splitting oxidation and carbon dioxide reduction reactions. Researchers at the Solar Fuels EFRC at the University of North Carolina &ndash; Chapel Hill made an important discovery &ndash; a metal complex catalyst, a polypyridyl complex of ruthenium, catalyzed both water oxidation and carbon dioxide reduction. Using this catalyst, an electrochemical cell was developed that split carbon dioxide into carbon monoxide and oxygen.&nbsp; As ruthenium is rare and expensive, a cheaper, more widely available alternative was needed; EFRC researchers discovered simple salts of copper (II), under the right conditions, react as robust electrocatalysts for oxidizing water. These results are an important step in developing a simple, highly effective approach for solar fuel production.</p>{5E80BB5B-2DB7-4A8E-9045-1B714FBEBD64}http://science.energy.gov/bes/highlights/2012/bes-2012-11-a/<img src='/~/media/bes/images/highlights/2012/11/nano-35c-thumb.jpg' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Unusual reaction eschews high temperatures and water to lock away climate-changing carbon dioxide.Thu, 02 May 2013 16:32:14 -0400 <p>Keeping power plants' emissions of carbon dioxide sequestered underground, even in the event of an earthquake or other geological upset, will be facilitated by transforming the carbon dioxide into a mineral, such as anhydrous magnesite. This reaction occurs more readily at high temperatures and requires additional water – conditions that may not be viable in an underground reservoir. Scientists at Pacific Northwest National Laboratory discovered a reaction that forms the desired mineral at the relatively low temperature of 95&deg;F and while recycling the water it needs. The team began with highly reactive nanometer-sized particles of an abundant mineral called forsterite, MgSiO₄. They introduced water-saturated supercritical carbon dioxide to the particles. They examined the forsterite surface using scanning electron microscopy and characterized the molecules formed using four specialized spectrometers. The results show that within 3 to 4 days, the forsterite, water, and carbon dioxide form a mixture of two magnesium-based minerals: nesquehonite, which contains water, and the desired anhydrous magnesite, which does not. Water is continually used and released in the process, with the water driving the reaction. Over 14 days of reacting, the carbon dioxide was transformed into magnesite and a highly porous silica phase.</p> {E9165276-CDE5-4BEE-8A57-97114FA4DC5B}http://science.energy.gov/bes/highlights/2012/bes-2012-10-a/<img src='/~/media/bes/images/highlights/2012/10/balke-thumb.jpg' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>New microscopy with nanometer-sized resolution may bring revolutionary new understanding to energy storage technologies.Thu, 02 May 2013 16:32:15 -0400 <p>A new scanning probe technique has led to the first measurements of the activation energy for Li-ion transport with nanometer resolution in the battery electrode material LiCoO₂. Understanding ionic transport at the level of individual grains and grain facets is of great importance in improving future energy storage (battery) energy and conversion (fuel cell) devices. Until now, activation energies for ionic transport have been actively explored by electrochemical techniques on the macroscopic and device level, allowing only average values for the activation energy to be determined. In this work, temperature-dependent electrochemical strain microscopy (ESM) is used to measure the activation energy of Li-ion transport in LiCoO₂ thin films on the nanometer scale, bridging the lengths scales of atomistic calculations and traditional macroscopic experiments. By understanding the local picture of Li-ion transport in electrode materials and its correlation with the microstructure, a better understanding of ionic flow through a battery can be developed, as is required for future improvements in battery technologies.</p> {CA0FB59C-36B2-4103-B265-64BD61B29DB7}http://science.energy.gov/bes/highlights/2012/bes-2012-10-b/<img src='/~/media/bes/images/highlights/2012/10/mpims-thumb.jpg' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Unique analysis of the reaction of propene with oxygen atom reveals the influence of electron spin on combustion chemistry.Thu, 02 May 2013 16:32:15 -0400 <p>Researchers at the Combustion Research Facility, Sandia National Laboratories, have obtained detailed insights into the oxidation of hydrocarbons, the first step in combustion, by use of a new gas-phase chemistry probe that combines synchrotron-based photoionization with mass spectrometry. The simple oxygen atom is an important combustion reactant as an oxidizer of hydrocarbon fuels. But reactions of individual oxygen atoms with other molecules are challenging to understand because of the unpaired electron of oxygen. Conventional understanding says that flipping the oxygen electron’s spin in the course of a reaction is “forbidden.” Synchrotron studies of the reaction of oxygen atoms with propene, a representative unsaturated hydrocarbon, differentiated between spin-allowed versus forbidden pathways and revealed unexpectedly large amounts of spin-forbidden products. This work is providing remarkable new insights that will profoundly affect our ability to accurately simulate the complex chemistry of combustion processes.</p> {150695B0-A7B5-4840-BCCD-9EE487B34F8E}http://science.energy.gov/bes/highlights/2012/bes-2012-10-c/<img src='/~/media/bes/images/highlights/2012/10/nitrogen-distribution-thumb.jpg' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>The first real-time images of two atoms vibrating in a molecule have been captured using a technique called laser-induced electron diffraction.Thu, 02 May 2013 16:32:15 -0400 <p>Developments in theory and ultrafast lasers are rapidly advancing our ability to observe and control the motions of atoms and electrons within molecules undergoing chemical transformations.  BES-supported scientists at Ohio State University and Kansas State University recently reported the first freeze-frame images of atoms in vibrating oxygen and nitrogen molecules by using the molecule’s own electrons to report the positions of its atoms with exquisite spatial (0.1 Å) and femtosecond (10^-15 sec) temporal resolution.  The technique, called laser-induced electron diffraction (LIED), uses the oscillating electromagnetic field of an intense, ultra-fast laser pulse to pull an electron from the molecule in a process known as photo-ionization and then hurl that same electron back to interact with and diffract from the molecular ion. The diffraction pattern from the re-scattered electron provides a snapshot of the molecular structure at the instant when it interacts with the atoms in the molecule.  The LIED technique offers a novel method for capturing the ultrafast motion of atoms within a molecule through the manipulation of one of its own electrons.</p> {9B831F68-2126-44A7-8A2E-4974C9F56F0B}http://science.energy.gov/bes/highlights/2012/bes-2012-10-d/<img src='/~/media/bes/images/highlights/2012/10/graphic-levin-atom-thumb.jpg' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Small addition of rare earth element makes a big difference in converting heat to electricity.Thu, 02 May 2013 16:32:15 -0400 <p>One of the best thermoelectric materials for converting heat to electricity was made 15% better based on discoveries in BES-supported research conducted at Ames Laboratory.  Adding a small amount of dysprosium to the thermoelectric material known as TAGS-85 (Ag_6.52Sb_6.52Ge_36.96Te₅₀) distorts the local crystalline structure and enables higher energy carriers to move preferentially through the material while presenting barriers to the transport of lower energy carriers.  Researchers found that the larger size of dysprosium atoms along with its local magnetic characteristics modifies the complex interplay between electronic and thermal transport in the material that is responsible for the electrical current that is generated in the material when one end of a thermoelectric device is heated to a higher temperature.  Adding dysprosium to TAGS-85 raises the thermoelectric figure of merit (ZT) for the material from 1.3 to 1.5, an improvement of 0.2 towards the goal of ZT = 2.0 needed for the commercialization of thermoelectric power generation.  Understanding how small levels of added atoms impacts thermoelectric properties helps researchers design even better thermoelectric materials.</p> {1B8A43C0-6464-4F1B-9DFE-A45240D61436}http://science.energy.gov/bes/highlights/2012/bes-2012-10-e/<img src='/~/media/bes/images/highlights/2012/10/kp-fossil-thumb.jpg' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Supercomputers + Software + electromagnetic images yield new way to discriminate underground deposits from surrounding geology.Thu, 02 May 2013 16:32:15 -0400 <p>Seismic imaging methods have a long and established history in identifying the geological structures that indicate hydrocarbon-bearing reservoirs.  However, these methodologies cannot discriminate between different types of reservoir fluids, such as brines, oils and gas, with the end result that significant time and money can go for offshore drilling without finding gas or oil.  New geophysical technologies using electromagnetic signals are sensitive to these differences if electrically resistive hydrocarbons are present. However, extracting the needed information is difficult, involving a mathematically elaborate process called inverse modeling. To make the analysis easier, researchers at Lawrence Berkeley National Laboratory have combined advanced geophysical imaging technologies with high-performance computing algorithms to make a powerful tool for subsurface electrical resistivity mapping, EMGeo - ElectroMagnetic Geological Mapper. It exploits parallel computing power, including LBNL’s National Energy Research Scientific Computing Center, to maximize the information that can be extracted from industrial electromagnetic surveys. The software has been licensed to several major oil and gas companies active in deep-water exploration, potentially saving billions of dollars in the detection of energy deposits. Additional research is focused on directly combining microseismic and electrical survey data for deepening the resolution of subsurface fluid maps within enhanced geothermal systems.</p> {32B9830F-0622-4D56-888B-B4473DC6045C}http://science.energy.gov/bes/highlights/2012/bes-2012-10-f/<img src='/~/media/bes/images/highlights/2012/10/puO2-molecule-thumb.jpg' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Observation of a plutonium nuclear magnetic resonance ends 50-year search and provides a key to deciphering its complex properties.Thu, 02 May 2013 16:32:15 -0400 <p>BES-supported research at Los Alamos National Laboratory, with collaborating scientists from the Japan Atomic Energy Agency, has led to the discovery of the nuclear magnetic resonance (NMR) signature for plutonium, the only spin-1/2 nucleus whose NMR signal had eluded detection despite 50 years of searching.  To find plutonium’s elusive NMR signature, the researchers used a highly chemically and isotopically purified sample of solid plutonium dioxide, cooled it to 3.95 Kelvin to slow the nuclear spin relaxation time, and scanned over a range of energies thousands of times larger than typically found for lighter elements.  The physical constant that is a signature of plutonium’s nucleus, the gyromagnetic ratio, determined through this discovery, also provides an all-important window into the local electronic environment of the plutonium nucleus, which determines the complex physical and chemical behaviors exhibited by plutonium in its metallurgy and chemical reactivity.  The long-awaited discovery of this NMR signature provides an important, non-invasive tool to improve our understanding of plutonium, its stability, reactivity, and properties, in solid state physics, chemistry, biology, and materials science.</p> {CB72E74E-BDD2-4760-A131-59B125B51199}http://science.energy.gov/bes/highlights/2012/bes-2012-10-g/<img src='/~/media/6B32687020B641409FBF1A56CEF64097.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Adding an oxide sieve, a layer containing nanocavities, to a catalyst surface makes the catalyst selective for specific reactions and increases efficiencies for chemical processes.Fri, 10 May 2013 11:21:35 -0400<p>Catalysts are compounds that enhance the speed of chemical reactions in a wide range of industrial chemistry applications. The Institute for Atom-Efficient Chemical Transformation (IACT), a DOE-supported Energy Frontier Research Center (EFRC), is developing new reactions and new catalytic materials for bioenergy production by combining advanced characterization, computer simulations, and materials synthesis.&nbsp;IACT researchers at Northwestern University and Argonne National Laboratory developed a new technique to modify existing oxide catalysts with a surface film that enhances the selectivity of the catalyst. These films contain &lt;2 nm diameter &ldquo;nanocavities&rdquo; made by adding a template during the atomic layer deposition process that is used to synthesize atom-precise films of oxides, metals, and other materials. Removal of the template after synthesis results in the nanocavities in the surface that provides a sieving effect, allowing separation of the reactant molecules and limiting reactions to a single particle. Because the thickness of the sieving layer is comparable in size to the reactant molecules, diffusional limitations that plague other materials are not present here. Ultimately, adding selectivity to intrinsically non-selective oxide catalysts is expected to decrease the cost for biofuels and bio-derived chemicals by decreasing the need for challenging and costly separations and increasing the product yields.</p> <p>The research utilized the Advanced Photon Source for characterization of the structures.</p>{7291F942-6029-42E7-A4ED-65057C685672}http://science.energy.gov/bes/highlights/2012/bes-2012-09-a/<img src='/~/media/FFCEEF8DB53E47E9847517FCB8BE469D.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>A step closer to an artificial system using sunlight to produce hydrogen from waterFri, 10 May 2013 11:21:34 -0400<p>In natural photosynthesis, multiprotein complexes termed photosystems capture solar energy and convert it to chemical energy.&nbsp; Sunlight is absorbed by a pigment in the photosynthetic reaction center of the photosystem, causing electrons to increase in energy.&nbsp; These high-energy electrons are then transported through a series of components to the water splitting/oxygen evolving complex in the photosystem where via the energy from the electrons, water molecules are split into oxygen and hydrogen ions. Using natural photosynthesis as a model, The Center for Bio-Inspired Solar Fuel Production EFRC at Arizona State University designed a completely artificial photosynthetic fuel production system.&nbsp; Researchers constructed synthetic versions of each of the key parts of electron absorption and electron transfer found in a natural photosystem.&nbsp; Ultrafast laser studies verified that the synthetic version functioned in a manner similar to the natural version. The water splitting/oxygen evolving component was added through collaboration with Pennsylvania State University.&nbsp; When illuminated, the final completed solar water splitting device produces oxygen and hydrogen gas from water.&nbsp; While this artificial system is inefficient and currently operated only on the laboratory scale, it is a step forward in finding a way to a viable solar fuel technology.</p>{D3D0CED3-F4E4-45D4-BC40-4B017CFC1F6E}http://science.energy.gov/bes/highlights/2012/bes-2012-09-b/<img src='/~/media/F1C03600DBEB4CA2853A1A63AD3D4EFA.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Rapid creation of carbon-fluorine bonds may lead to improved production of drugs, agrochemicals and positron emission tomography (PET) tracers.Fri, 10 May 2013 11:21:35 -0400<p>Catalysts for low-temperature and selective substitution of bonds in hydrocarbons to produce specific functionality are central to the development of advanced technologies that can provide dramatic improvements in the utilization of energy. The Center for Catalytic Hydrocarbon Functionalization (CCHF), a DOE funded Energy Frontier Research Center, is developing efficient catalysts for conversion of hydrocarbons into higher value materials. CCHF researchers at Princeton University and the California Institute of Technology discovered a manganese porphyrin catalyst (lower left molecule in figure) that selectively fluorinates carbon-hydrogen bonds under mild conditions using simple fluorides.&nbsp;The new fluorination system can be applied to a variety of alkanes, terpenoids and steroids&mdash;industrial molecules that are used in agriculture, pharmaceutical production, and medical positron emission tomography (PET) scan tracers.&nbsp;The yields of the reaction are sufficiently high and the techniques are sufficiently simple that the reaction can be performed without specialized apparatus.&nbsp; Given that the source of F in this one-step, one-pot protocol is fluoride ion, applications to incorporate isotopically-labeled F into a wide variety of biomolecules and synthetic building blocks can be expected. </p> <p>A patent application has been filed on the methodologies and resulting catalysts.</p>{69410B29-B4B8-422B-9909-BD007580F9D5}http://science.energy.gov/bes/highlights/2012/bes-2012-08-a/<img src='/~/media/A7C71133E9E44C73BDB4C360EDFEF132.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Squeezing creates new class of material built from clusters of carbon atoms.Fri, 10 May 2013 11:21:34 -0400<p>How do you dent diamond, one of the Earth&rsquo;s hardest materials? Researchers supported by the Energy Frontier Research in Extreme Environments EFRC&nbsp;created a new substance that can do just that. To make the new material, the researchers started with &lsquo;buckyballs,&rsquo; soccer-ball shaped cages composed of sixty carbons, and mixed them in a liquid solvent called xylene.&nbsp; The molecules of xylene served to &ldquo;link&rdquo; the buckyballs together in a regular, crystalline pattern like beads on a string. Finally, they squeezed the mixture in a diamond anvil cell in-situ in the synchrotron beam of the Advanced Photon Source. &nbsp; Something extraordinary happened around 320,000 times atmospheric pressure; the buckyballs collapsed and formed disordered, amorphous clusters but the xylene molecules held fast and still tethered the amorphous pieces together in a pattern like before. The resulting, never-before-seen structure was surprisingly hard; strong enough to dent the diamond anvil. The material stayed in the same structure even after the pressure had been released, which makes it potentially useful for a variety of different devices, especially future electronics. (<a href="/news/in-focus/2012/08-27-12/">Excerpt from DOE-SC's "In&nbsp;Focus"</a>)</p>{FEE7DB99-A318-4132-9B39-4807D5831AB0}http://science.energy.gov/bes/highlights/2012/bes-2012-08-b/<img src='/~/media/A99AF3559C0B49B1A8C905A3DE498E86.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>New microscopy method opens the door to understanding atomic-scale variations in chemistry and improved materials performance in solid oxide fuel cells.Tue, 04 Jun 2013 16:04:09 -0400<p>A quantitative understanding of the distribution, arrangement and geometry of oxygen vacancies in functional oxides has been a long-standing challenge that needs to be addressed in order to control the physical properties of oxide materials for energy applications. With this information, researchers can begin to understand the behavior of oxygen vacancies and the nature of their interactions, especially across interfaces, in a fuel cell. In this research, a team led by Oak Ridge National Laboratory researchers used scanning transmission electron microscopy to determine the distribution of oxygen vacancies in a fuel cell cathode material, at a resolution less than a single unit cell, through local lattice parameter measurements. This method quantifies oxygen vacancy distribution and homogeneity, which directly control the operation of solid-oxide fuel cells and are intrinsically coupled with magnetic, electronic, and transport properties of oxides. This new approach was successfully demonstrated in lanthanum strontium cobaltite thin films grown on different substrates that have been proven previously to produce variations in oxygen vacancy concentration. Researchers were able to directly image and measure the oxygen vacancies, with the experimental results shown to be consistent with theoretical models.&nbsp;The research opens a new pathway to inform the development of improved fuel cell technologies.</p>{01387CA8-3D86-4340-999D-8A58F6777792}http://science.energy.gov/bes/highlights/2012/bes-2012-07-a/<img src='/~/media/bes/images/highlights/2012/07/rogers-thumb.jpg' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>High-efficiency compound semiconductor solar cells can now be printed on flexible, plastics.Thu, 02 May 2013 16:32:16 -0400 <p>BES-supported research at the University of Illinois has resulted in an extensive intellectual property portfolio related to printable, high performance flexible and stretchable electronics and photovoltaics.  This fundamental research answers basic questions related to growth and manufacturing use of single crystalline semiconductors, dielectrics, metals, and devices formed from them.  This process also includes the use of a micro-transfer printing process that enables integration of pre-formed circuit elements to almost any substrate, including flexible types of plastic that can be integrated with optical over-layers for directing and focusing the light.  This research has directly led to a development program on concentrator photovoltaic modules, in partnership with Semprius Corporation, under the DOE Energy Efficiency and Renewable Energy’s <a href="http://www1.eere.energy.gov/solar/sunshot/incubator.html">SunShot Initiative Program </a>with the goal of establishing new materials strategies and manufacturing methods for low cost, high performance photovoltaic modules.  Semprius Corp and MC10, another startup company focused on stretchable electronics for biomedical applications, have licenses for applications in photovoltaics, flexible electronics and large area displays.  In 2012, Semprius set a new world record for photovoltaic module efficiency, reaching 33.9 percent.</p> {C85B942E-043A-4E98-9C4B-B09786ECD2D4}http://science.energy.gov/bes/highlights/2012/bes-2012-07-b/<img src='/~/media/34DCFCF74E5649CDA7424992D2865AA9.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Nanoscale features in rocks enable more carbon dioxide to be trapped as a solid carbonate material underground.Fri, 10 May 2013 16:30:03 -0400<p>Advanced experiments and computations have shown that underground carbonate mineral nucleation and growth is strongly dependent on nanoscale features such as the pore structure and surface topography of permeable rocks and the interfacial energies between rock surfaces and solid carbonates. This research at the Lawrence Berkeley National Laboratory&rsquo;s Center for Nanoscale Control of Geologic CO₂, Washington University in St. Louis, and Oregon State University provides the quantitative parameters necessary to develop advanced models that describe how nucleation and growth of carbonate occur in porous media that contain multiple minerals with different surface properties and micro- to nanoscale pores. In carbon capture and storage, CO₂ is captured from power plant exhaust and other sources and injected underground into porous rock formations where it mixes with ambient salt water and may remain for 1000&rsquo;s of years. Although it is expected that CO₂ can be transformed to carbonate minerals, it is unknown how fast this will occur and how the addition of new carbonate mineral in the rock formations will affect the short and long-term behavior of the system. This research will enable more realistic modeling of mineral formation from the injected CO₂ and thus increase the pace of deployment of this critical energy technology.</p>{9F31DFD5-71FD-4EB0-9ACC-7B6A2E1E5E79}http://science.energy.gov/bes/highlights/2012/bes-2012-06-a/<img src='/~/media/bes/images/highlights/2012/06/ccei-thumb.jpg' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>House-of-Cards structure leads to improved zeolite catalyst.Thu, 02 May 2013 16:32:16 -0400 <p>Increasing demand for energy and materials has led to an accelerated research effort in the development of renewable chemicals for a sustainable economy. Efforts within the Catalysis Center for Energy Innovation (CCEI), a DOE-funded Energy Frontier Research Center (EFRC), are aimed at realizing novel catalytic processes for production of chemicals and fuels from biomass-derived feedstocks by bridging catalyst design, reaction engineering and fundamental understanding of reaction mechanism. The researchers used a novel and simple synthesis technique, called repetitive branching, to stack the thin zeolite sheets at right angles generating a "house-of-cards" shaped crystal. By creating zeolite crystals with large-pore "highways," which are about 10 times bigger than the zeolite pores, chemicals and molecules can pass rapidly through the channels to reach the smaller, reactive pores within the crystal. This results in faster, more selective, and more stable catalysts, produced at the same cost as traditional zeolite catalysts. Research was performed at the University of Minnesota and has been licensed to Argilex.</p> {323D9F6D-ED9E-46EC-BD7C-813393D77542}http://science.energy.gov/bes/highlights/2012/bes-2012-06-b/<img src='/~/media/5548C19F304E4E6DBB96A9365B427649.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Enzymes originating from marine sponges were intentionally altered to create a new enzyme that can make semiconductors in artificial cells.Tue, 04 Jun 2013 16:04:09 -0400<p>The processes of genetic mutation and natural selection have been accelerated in the laboratory to evolve proteins that catalyze the synthesis of semiconductors in aqueous solutions at low temperature. The critical challenge for mimicking nature&rsquo;s methods for the synthesis of high-performance materials has always been overcoming the toxicity of these materials to living cells. To address this challenge, research at the University of California&ndash;Santa Barbara focused on mutating the DNA coding for the silicatein enzyme that catalyzes marine sponge skeleton synthesis. The resulting DNA strands were introduced into microscopic liquid bubbles, comprised of polystyrene micro beads in oil-water emulsions, which acted as surrogates of living cells. The bubbles contained all the biological constituents needed to express the mutant DNA molecules, synthesize the new silicatein molecules encoded by the DNA mutants, and &ndash; for the few new silicateins with exactly the right structure &ndash; support the catalytic synthesis of the new semiconductors. High-speed fluorescence laser sorting was used to recognize and select mutants that produced the silicateins capable of catalyzing the synthesis of desired semiconductors. The success of this biotechnology route to semiconductors - materials that have provided a cornerstone for economic and technological growth &ndash; opens the door to an exciting new strategy for mimicking the genetic evolution of biology for synthesizing high-performance materials.</p>{5C548C32-C0EB-4655-8D37-EE34E68CEA69}http://science.energy.gov/bes/highlights/2012/bes-2012-05-a/<img src='/~/media/938DFCA0F40548D0A12A91F3E7F75E67.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Novel, liquid-less design promises to improve long-term stability and durability of dye-sensitized solar cells while hitting high efficiency marks.Fri, 10 May 2013 11:21:32 -0400<p>Current solar cell technologies are largely constrained by high production costs, low operating efficiency, and limited durability.&nbsp;A low-cost alternative to current silicon-based solar cell devices are thin film solar cells, such as dye-sensitized solar cells (DSSCs). DSSCs are made up of inexpensive, environmentally-benign titanium dioxide nanoparticles coated with light-absorbing dye molecules, and a liquid electrolyte.&nbsp; Research by the Argonne Northwestern Solar Energy Research (ANSER) EFRC at Argonne National Laboratory and Northwestern University has solved long-standing corrosion and durability problems associated with the liquid electrolyte. The corrosive, volatile liquid was replaced with a novel semiconducting inorganic solid, resulting in a solar cell that has competitive conversion efficiencies (10%) while withstanding high temperatures, high levels of humidity, and accelerated aging tests.&nbsp;The solid semiconductor consisting of cesium tin iodide (CsSnI₃) can be processed in solution, an appealing characteristic for keeping manufacturing costs low.&nbsp;The semiconductor also enhances light absorption of the DSSC in the red region of the solar spectrum, thereby outperforming conventional DSSCs. This discovery could lead to new solar cells that are both longer-lasting and highly efficient, while costing less to manufacture.&nbsp;A patent has been filed for this development.</p>{55E59475-DA49-4A22-8B96-502CFFED2AAB}http://science.energy.gov/bes/highlights/2012/bes-2012-05-b/<img src='/~/media/ADEC60372B184F41957E860AF1A0A46C.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Visualization of electron pair binding confirms predictions about how high temperature superconductivity works.Fri, 10 May 2013 11:21:33 -0400<p>By measuring how strongly electrons are bound together, forming &ldquo;Cooper pairs&rdquo;, in an iron-based superconductor, scientists at the Center for the Emergent Superconductivity Energy Frontier Research Center, Brookhaven National Laboratory, Cornell University, and St. Andrews University, with materials developers at AIST in Japan, provide direct evidence that magnetism holds the key to this material&rsquo;s ability to carry current with no resistance. Several groups of theorists had hypothesized that if the electrons in a superconductor have their magnetic moments pointing in opposite directions, they could overcome their mutual repulsion to join forces in so-called Cooper pairs &mdash; thus carrying current with no loss. According to the theory, the strength of the &lsquo;glue&rsquo; holding electron pairs together would be different for specific electrons and depend on the direction that the electrons are traveling &mdash; with the pairing usually being stronger in a given direction than at 45&deg; to that direction.&nbsp;The researchers figured out how to measure the predicted direction dependence (anisotropy) in the energy necessary to unbind a pair by using a specially developed application of scanning tunneling microscopy. Their novel method, known as &ldquo;multi-band Bogoliubov quasiparticle scattering interference,&rdquo; discovered the anisotropic pairing &ldquo;signature&rdquo; predicted for three electronic bands of a model superconductor, lithium iron arsenide.</p>{6FF27E78-51A2-4D7A-AB5A-B3F57FD6CE24}http://science.energy.gov/bes/highlights/2012/bes-2012-05-c/<img src='/~/media/CE7DE7FE393341C3A794087E1FBBCA97.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>New scalable, high power energy storage possible with carbon-electrolyte slurries.Fri, 10 May 2013 11:21:33 -0400<p>Scientists at Drexel University studying the properties of carbon slurries have discovered that the electrochemical and physical flow characteristics of such slurries are favorable for a new grid-scale storage concept called the electrochemical flow capacitor (EFC). In work supported by the Fluid Interface Reactions, Structures, and Transport (FIRST) Center, a DOE Energy Frontier Research Center, researchers have discovered that, just like supercapacitors, energy is stored in the electric double layer of charged carbon particles in an electrolyte slurry.&nbsp;A flowable carbon-electrolyte slurry could serve as the active material for an EFC, in which the charged slurry is handled in a similar fashion to flow or semi-solid battery fluids (<em>i.e.</em>, for charging/discharging, the slurry is pumped into an electrochemical cell; for energy storage, the charged slurry is pumped into reservoirs).&nbsp;This new concept shares the major advantages of supercapacitors and flow batteries, providing rapid charging/discharging and excellent cyclability, while enabling the decoupling of the power and energy ratings. The study reported promising initial EFC performance data for carbon slurries obtained under static and intermittent flow operations. This approach may reduce the use of polymer separators, metal current collectors and packaging materials; these passive elements increase the cost and weight in current devices without contributing to the charge storage.</p>{529E0482-D5C8-4C16-B717-D41C8841134B}http://science.energy.gov/bes/highlights/2012/bes-2012-04-a/<img src='/~/media/4D01B398CDBB4AE990B70F0A936F03A4.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Researchers have created an environmentally-friendly plastic coating that converts a wide range of electrical conductors into air-stable components for flexible, less expensive electronics.Fri, 10 May 2013 11:21:31 -0400<p>Organic-based thin-film optoelectronics, such as solar cells, hold great potential as affordable consumer electronics. However, most printed optoelectronics require at least one electrode be a metal having a work function (the amount of energy needed to remove an electron) that is low enough to inject electrons into, or collect, electrons from an organic semiconductor. Unfortunately such metals are very reactive and easily oxidized, which reduces performance of the electrode.&nbsp;To avoid this problem, a controlled fabrication environment and protective barrier are needed to prevent water and/or oxygen exposure, increasing manufacturing complexity and cost. Researchers at Georgia Tech, part of the Center for Interface Science: Solar Electric Materials (CISSEM) EFRC, discovered a universal approach, <em>i.e.,</em> applicable to many materials, for producing a low work function electrode that is stable in air. By &ldquo;sticking&rdquo; (through physisorption) an ultrathin layer (1 to 10 nanometers) of a commercially available, environmentally-friendly polymer with amine-containing aliphatic chains to a wide range of conductor surfaces, an air-stable, high performance electrode was created.&nbsp; To illustrate this approach&rsquo;s promise, the researchers demonstrated, for the first time, a completely plastic organic solar cell on a flexible substrate, an approach that would lower manufacturing costs for solar cells and other electronics.</p>{EEAE22D1-6218-4B8B-A9D3-814187B558E5}http://science.energy.gov/bes/highlights/2012/bes-2012-04-b/<img src='/~/media/BACC4E8B33E147C8A05600BC20173A58.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>New catalyst structures for fuel cells in vehicles improve activity and stability compared to commercial platinum counterparts.Fri, 10 May 2013 11:21:32 -0400<p>A key technical challenge for improved performance of the polymer electrolyte fuel cells used in transportation is increasing both activity and stability of the cathode catalyst. The current industry standard for the cathode catalyst is platinum (Pt) nanoparticles on a high-surface area carbon (C). In this study, researchers at the Center on Nanostructuring for Efficient Energy Conversion EFRC at Stanford University developed a high surface area, meso-structured Pt thin film catalyst that exhibits higher specific activity for oxygen reduction than the commercial catalyst.&nbsp;Oxygen reduction to form water is a critical component of the chemical activity in the fuel cell. An accelerated stability test demonstrated that the meso-structured Pt thin film also is significantly more stable than the commercial catalyst. &nbsp;Research reveals that the high turnover frequency and excellent durability is due to the meso-structure. Specifically, the morphology of the structure results in fewer under-coordinated Pt sites than Pt/C nanoparticles, a key difference that improves the specific activity and surface chemistry. The improved catalyst activity and stability resulting from this structure could enable development of high-performance gas diffusion electrodes resistant to corrosion even under the harsh conditions of start-up, shut-down, and/or hydrogen starvation.</p>{1A3C1A3E-E38D-4704-8F3B-11E27CBEAF48}http://science.energy.gov/bes/highlights/2012/bes-2012-04-c/<img src='/~/media/D8C9029215DC47F38C0A450F997FC23D.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Overcoming a fundamental dilemma in making polymers that combine strength and toughness with spontaneous healing capability.Tue, 04 Jun 2013 16:04:09 -0400<p>A breakthrough has been achieved in designing mechanically robust polymeric materials that can spontaneously repair themselves, a key feature of biological systems, without any external help from light, heat, or healing agents. Despite significant previous efforts, progress towards the realization of spontaneously self-healing polymers has been hampered by a fundamental dilemma: the need to retain mechanical stiffness/strength while allowing the rapid material dynamics required for spontaneous healing. In research at the University of California, Irvine, this challenge has been addressed by designing and synthesizing a polymer that self-assembles into a nanostructured material incorporating both &ldquo;hard&rdquo; and &ldquo;soft&rdquo; phases. While the hard phase imparts mechanical toughness, the soft phase, comprising polymer segments with a network of hydrogen bonds, provides dynamic, self-healing capability. Under mechanical stress, connections between polymer chains within the soft phase can rupture but can readily reconnect through hydrogen bonding interactions, thereby effectively mending the damage. The development of polymers that can spontaneously repair themselves after mechanical damage would significantly improve the safety, lifetime, energy efficiency and environmental impact of many man-made materials. A patent application has been filed and a small start-up company has been formed with the goal of commercializing this technology.</p>{C6F56625-C338-4900-9454-C5CF34C50A47}http://science.energy.gov/bes/highlights/2012/bes-2012-03-a/<img src='/~/media/bes/images/highlights/2012/03/cgs-smit-hydrocarbon-separation-thumb.jpg' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Novel material for purifying gases could significantly lower industrial energy costs.Thu, 02 May 2013 16:36:31 -0400 <p>Scientists at the University of California, Berkeley–based EFRC, the Center for Gas Separation Relevant to Clean Energy Technologies, have experimentally confirmed the theoretical predictions that a novel metal-organic framework (MOF) material could purify several industrially important gases at nearly ambient conditions. MOFs are crystalline compounds consisting of metal clusters attached to organic molecules to form porous structures. Neutron diffraction of the MOF reveals a large surface area and exposed iron cation sites, which can preferentially adsorb unsaturated hydrocarbon molecules. It exhibits excellent performance for the purification of hydrocarbon gases, such as methane, ethylene, and propylene, useful for fuels and plastics, from gas mixtures at conditions much milder than those currently used for the separation of these gases. This patented discovery could result in cost savings for the oil and chemical industries and lower their environmental impacts by replacing existing large-scale energy-intensive gas separation processes. Current production involves cracking longer chain hydrocarbons at high temperatures (up to 500-600 °C) and separating the resulting products at high pressures and cryogenic temperatures (-100 °C). This material may also be capable of purifying natural gas streams containing a number of impurity gases.</p> {B63CFAA5-2A5D-4CCA-BE2E-7F9EF16C33E6}http://science.energy.gov/bes/highlights/2012/bes-2012-03-b/<img src='/~/media/C8B21ECAE7AC41DDB54ECFA38B7EDB78.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>New nanostructured electrodes have 10 times the charging speed and higher battery power.Fri, 10 May 2013 11:21:31 -0400<p>Scientists at the University of California, Los Angeles&ndash;based EFRC, Molecularly Engineered Energy Materials, have developed a novel approach to synthesize nanostructured high performance electrodes useful for the next generation lithium ion batteries. By directly coating active nanocrystals onto pre-formed three-dimensional conducting carbon nanotube (CNT) scaffolds, the need for the binders for structural stability at the nanostructured interfaces was eliminated &ndash; an important advance since binders can decrease the overall battery performance. Use of nanometer-sized particles in electrodes drastically reduces the charging times of batteries and supercapacitors because their high surface area offers ample sites for rapid movement of lithium ions, the material that carries the electrical charge. This conformal coating method provides critical features for high-performance electrodes, including effective pathways for electronic transport, high active-material loading, structural robustness and mechanical flexibility due to the excellent intrinsic properties of the CNT scaffold and the high surface area and shortened lithium-diffusion length of the nanocrystals. Electrodes based on titanium dioxide nanocrystals charged to 80% of full capacity in 5 minutes and showed negligible energy loss after a few hundred cycles.</p>{6968F56D-89D8-4BAF-A693-DB49B02A7299}http://science.energy.gov/bes/highlights/2012/bes-2012-03-c/<img src='/~/media/75A69C29A3F547008DE5E36A43B2E1BE.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Experts look at past nuclear accidents and potential scenarios to identify gaps in understanding nuclear fuel behavior.Fri, 10 May 2013 16:24:16 -0400<p>When the editors of Science wanted to highlight to their worldwide audience the gaps in our current understanding of nuclear fuel, recently brought to the fore by the accident at Japan&rsquo;s Fukushima reactors following the earthquake and resulting tsunami, they turned to three members of the Materials Science of Actinides EFRC (representing Notre Dame, University of Michigan, and University of California-Davis) to provide that expertise.&nbsp;The primary issue these experts point out is that the materials science and chemistry interactions of fuels in an accident scenario (heating, introduction of seawater, etc.) are very complex and not well known.&nbsp;During the Fukushima shutdown and subsequent flooding, this lack of scientific understanding resulted in a number of uncertainties in emergency response decisions.&nbsp;Unknown factors included the corrosion of the fuel, the chemical complexes formed, the rate of gas generation, and other degradation processes.&nbsp;One problem is that existing studies cannot be extrapolated to the conditions of a core-melt incident. Studies of simulated core-melt events and actual damaged fuel are needed to understand the complicated reactions involving radionuclides and the role of nano-scale actinide materials in promoting the breakdown of fuels. An understanding of the factors that determine the release of radionuclides from damaged fuel elements is central to minimizing impacts on the environment and human health.</p>{C96ABF32-A742-4480-AA6E-DBD9DACF8858}http://science.energy.gov/bes/highlights/2012/bes-2012-02-a/<img src='/~/media/282736F172E64753A6B6F6F65320E625.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>“One pot” catalyst converts up to 20% of dry biomass to a critical chemical used in biofuel production.Fri, 10 May 2013 11:21:28 -0400<p>Furfural is a useful chemical that can be obtained from plant biomass. In addition to being a component in synthesis of industrial and household products, furfural has increasing potential as a non-petroleum-based, renewable building block for liquid transportation fuels.&nbsp;Strong acids have typically been used to make furfural by converting sugars such as xylose from hemicellulosic polysaccharides, a major component of plant biomass. However, this can result in breakdown of furfural to unwanted products, reducing overall yield. Research in the C3Bio Energy Frontier Research Center (EFRC) demonstrated that use of maleic acid, a weak acid, provides a more efficient method to obtain furfural.&nbsp;The researchers at Purdue University used kinetic studies to determine optimal temperatures and times for the two-step process using maleic acid first to extract xylose from untreated biomass, either maize, switchgrass, pine or poplar, and then to convert the xylose to furfural. Because maleic acid can accomplish both conversion steps, this &ldquo;one-pot&rdquo; strategy produced furfural at higher yields and resulted in less degradation of both xylose and furfural than use of strong acids.&nbsp;Further, this process may be less expensive and more environmentally friendly than other available technologies.</p>{284C89CB-6EE5-4F98-8AFF-C931A52408E3}http://science.energy.gov/bes/highlights/2012/bes-2012-02-b/<img src='/~/media/4AE2943B0D1A40E29166D9D2EB53D1C5.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>A scalable catalytic process improves the yield of biofuels by 40%.Fri, 10 May 2013 11:21:29 -0400<p>Catalytic fast pyrolysis (CFP) is a promising technology for the production of renewable aromatic compounds, including commercially important chemicals such as benzene, toluene, and xylenes, directly from solid biomass.&nbsp;In this single-step process, biomass, including wood, agricultural wastes and fast-growing energy crops, is fed into a fluidized-bed reactor where the biomass thermally decomposes to form pyrolysis vapors, the gases released from the processing. These pyrolysis vapors then enter the zeolite catalysts, which are also in the fluidized-bed reactor, and are converted into the desired aromatic compounds and olefins, types of hydrocarbon, along with carbon monoxide, carbon dioxide, water, and coke, a high-carbon fuel.&nbsp;The spent catalyst and coke are sent to a regenerator where they are burned. The advantages of the new process are: 1) all the desired chemistry occurs in one single reactor, 2) the process uses an inexpensive silica&ndash;alumina catalyst, and 3) aromatics and olefins are produced that fit easily into existing infrastructures.&nbsp; Research was performed at the University of Massachusetts as a part of the Catalysis Center for Energy Innovation EFRC, and has been licensed to Annelotech.</p>{22A68D8F-2D69-47B5-8B56-8D5155A0AF70}http://science.energy.gov/bes/highlights/2012/bes-2012-02-c/<img src='/~/media/805EA3C9556C490FA8D33F9F4677B432.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Biomechanical studies challenge current depictions of plant primary cell wall architecture.Fri, 10 May 2013 11:21:29 -0400<p>Growing plant cells are surrounded by a primary cell wall consisting predominantly of polymers of sugars (cellulose, hemicellulose, and pectin).&nbsp;Xyloglucan, typically referred to as hemicellulose, is widely believed to act as a tether between cellulose fibers, limiting cell enlargement and regulating cell wall mechanical properties. To test this model, Center for Lignocellulose Structure and Formation EFRC researchers at Pennsylvania State University assessed the biomechanical properties of the cell wall.&nbsp;Experiments examined the ability of primary cell walls to undergo creep &mdash; irreversible increases in the length of the walls due to loosening of the connections between cell wall components &mdash; in response to three types of enzymes, termed endoglucanases, that causes breakdown(hydrolysis) of either xyloglucan, cellulose, or both. &nbsp;The xyloglucan-specific and cellulose-specific endoglucanases, either by themselves or in combination, failed to induce creep; endoglucanases that hydrolyze both xyloglucan and cellulose induced a high creep rate and were able to break down the cell wall. These results suggest xyloglucan does not act as a load-bearing tether between cellulose microfibrils. Rather, a minor xyloglucan component may be located in the limited regions of tight contact between cellulose fibers, playing an important role in wall mechanics.</p>{919B9B1C-E837-4B31-99B7-7C46FEC0B565}http://science.energy.gov/bes/highlights/2012/bes-2012-02-d/<img src='/~/media/A8B670E8FCE14632BBB8A00367828038.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>A single reversible catalyst enables energy to be both stored and released on demand.Fri, 10 May 2013 11:21:29 -0400<p>Alternative energy sources like wind and solar produce intermittent power that must be stored for later use when the wind stops blowing or the sun sets.&nbsp;One storage mechanism is to transform electrical energy from solar and wind into chemical energy like hydrogen, but this can be complex and costly.&nbsp;To produce hydrogen efficiently, Center for Molecular Electrocatalysis (CME) researchers are designing a hydrogen splitting catalyst based on the hydrogenase enzyme found in nature. Hydrogenase cleaves two linked hydrogen atoms (dihydrogen) into electrical energy, and it can reverse the reaction to form dihydrogen.&nbsp;This enzyme also has features CME researchers want &ndash; a single catalyst that works at ambient temperature and pressure, and an active site that uses abundant metals such as iron or nickel.&nbsp;To build the synthetic catalyst, molecular strands called ligands were attached to a nickel active site.&nbsp;Using theory and experiments, researchers varied size, shape, and electronic properties of the ligands to &ldquo;tune&rdquo; catalytic activity.&nbsp;One nickel complex displayed reversible dihydrogen production and cleavage with high efficiency &ndash; the first example of a molecular complex to catalyze these reversible reactions.&nbsp;While the catalyst is slow, it wastes little energy and marks an important first step towards improving capabilities for energy storage.</p>{2DD28828-1A73-48B0-9DDB-99D24FD1EB67}http://science.energy.gov/bes/highlights/2012/bes-2012-02-e/<img src='/~/media/D98C123D059A443294201C6B5047C261.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Magnetic resonance imaging (MRI) method non-destructively images the chemical and structural changes in a lithium ion battery.Fri, 10 May 2013 11:21:30 -0400<p>The most attractive, highest energy density anode material for a lithium (Li) ion battery is lithium metal itself.&nbsp;However, Li metal battery commercialization has been hampered by safety concerns about the formation of extended Li metal microstructures that can create a short circuit between electrodes.&nbsp;Two key questions emerge: (1) In what form is the Li metal deposited - bulk, porous (aka mossy), or dendritic? and (2) How can Li dendrites be prevented?&nbsp;As part of the Northeastern Center for Chemical Energy Storage EFRC, a research team from New York University, Stony Brook University, and Cambridge University has developed a suite of magnetic resonance imaging (MRI) techniques for characterizing deposited lithium inside a working battery cell. Because the radio frequency energy used in MRI has a limited penetration into bulk Li metal but much greater penetration into more porous microstructures, the amount of Li metal microstructure formed during cycling can be quantified by measuring the increase in signal strength.&nbsp;In 2-D and 3-D⁷LI MRI techniques, bulk magnetic susceptibility has different signals for the dendrites and the Li metal moss that grow on the Li metal anode, revealing both the location and nature of the microstructural lithium under the operating conditions of the battery.</p>{0012DAE9-742F-4195-A7D5-B1DA6AA0A7B2}http://science.energy.gov/bes/highlights/2012/bes-2012-02-f/<img src='/~/media/51F989FDF7484AC98CFADE863CA10563.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Antimony atoms with uncoordinated electrons block flow of heat in thermoelectric materials.Fri, 10 May 2013 11:21:30 -0400<p>The primary challenge in designing thermoelectric materials with efficient heat-to-electricity conversion is maintaining good transmission of electrons through an atomic structure designed to have low thermal conductivity.&nbsp;Adding nanosized defects and impurities to the material can block the lattice vibrations responsible for heat transport, but this approach can also degrade electrical transport and may reduce thermally stability.&nbsp;In the search for new thermoelectric materials which have intrinsically low thermal conductivity, researchers in the Revolutionary Materials for Solid State Energy Conversion EFRC discovered a direct link between the structure and bonding of compounds containing antimony atoms and the lattice thermal conductivity.&nbsp; Antimony (Sb) ions can assume either a pentavalent (+5) state with coordination to four nearest neighbor atoms via bonding or a trivalent (+3) state with coordination to only three nearest neighbor atoms and the retention of two &ldquo;lone-pair&rdquo; electrons in one of the four Sb coordination sites.&nbsp;Theoretical lattice dynamics computations determined that strong anharmonicity is induced in the lattice vibrational spectrum of Sb compounds with &ldquo;lone-pair&rdquo; electrons.&nbsp;Because lattice anharmonicity drives thermal resistance in solids, these compounds and others like them that contain loan pairs should exhibit intrinsically low thermal conductivity that is &ldquo;built into&rdquo; the crystal structure.&nbsp;This was confirmed experimentally in copper antimony selenide semiconductors.</p>{E2A39ABC-8F65-4A8A-81F4-A9504009EC4A}http://science.energy.gov/bes/highlights/2012/bes-2012-02-g/<img src='/~/media/0FBEBABFBACE42A2B8CA99BBAD123BB3.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Short pulses of light reveal an intrinsic conducting surface that is different from the bulk.Tue, 04 Jun 2013 16:04:09 -0400<p>For an exotic new class of materials called &ldquo;topological insulators,&rdquo; an electrically conducting skin covering the insulating interior of the materials was detected, confirming predictions made in 2007.&nbsp; To do this research, a highly sensitive technique that can distinguish between the electrically conducting skin and the insulating bulk was developed by scientists at the Johns Hopkins Institute of Quantum Matter. The experiment employed short pulses of terahertz light (used in airport scanners) with linear polarization &ndash; analogous to what happens to sunlight as it passes through polarized sunglass lenses. The polarization of the transmitted light was found to have rotated over 65 degrees when compared to the incident light. This &ldquo;Colossal Terahertz Kerr rotation&rdquo; furnishes the first direct evidence for an electrically conducting surface layer on a topological insulator. This probe will be a critical tool to understand and perfect the material&rsquo;s properties. The high electrical conductivity might contribute to a new generation of high performance low loss processors and the unique character of the surface states may play a key role in realizing the promise of quantum computing.</p>{A6B90BBF-9C76-4A05-B85A-4E62FAB3AF79}http://science.energy.gov/bes/highlights/2012/bes-2012-01-a/<img src='/~/media/bes/images/highlights/2012/01/mason-thumb.jpg' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Arrays of superconducting islands open up the possibility for tailor-made properties and functionality.Thu, 02 May 2013 16:36:32 -0400 <p>Superconductors conduct electricity without efficiency losses, and have potential applications for the electric grid and other energy uses. In this research, supported by BES at the University of Illinois at Urbana-Champaign, researchers fabricated arrays of superconducting niobium islands on gold films and measured the temperature-dependence of the electrical resistance as a function of island separation. The results demonstrated that the long-range connectivity between the islands occurs in a way that cannot be explained by current theories. For example, at large island spacing the system seems to systematically approach a zero-temperature metallic state, which cannot be explained by the conventional theory of metals. These results may also explain the appearance of anomalous zero-temperature metallic states in other materials, such as some semiconducting and superconducting thin films. The ability to tune the superconducting properties of the island system through island geometry, spacing, material properties and disorder provides a new way to investigate similar inhomogeneous correlated materials and may open new avenues to design material systems with desired functionality.</p> {B2110407-341F-4913-BBBE-A5D2F6DBCEC9}http://science.energy.gov/bes/highlights/2012/bes-2012-01-b/<img src='/~/media/bes/images/highlights/2012/01/emc2-abruna-metal-oxide-nanosheets-thumb.jpg' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>New, scalable manufacturing technique grows metal oxide nanosheets with astronomical aspect-ratios, opening the door to intriguing material properties.Thu, 02 May 2013 16:36:32 -0400 <p>Scientists at the Energy Materials Center at Cornell (emc2), a DOE Energy Frontier Research Center, have developed a novel synthesis for millimeter-length nanosheets of the complex metal oxide, sodium cobalt oxide (Na_xCoO₂). The scalable method is capable of producing tens of thousands of nanosheets with dimensions large enough to use in devices. Similar to the unusual 2-D form of carbon known as graphene, nanosheets of metal oxide crystals present exciting opportunities to study and exploit their novel electronic, ferromagnetic, magneto-optical, electrochemical, catalytic, and photoresponsive properties, while being stable at high temperatures and in severe chemical environments. Researchers used an electric field to move, or demix, the sodium (Na) cations in a pellet of mixed metal oxides.  The nanosheets formed in the resulting Na-enriched regions of the pellet have thicknesses in the tens of nanometers while their lateral lengths are millimeters, resulting in a very dramatic, anisotropic aspect ratio (10^–5: 1 : 1). The stacks of nanosheets are readily peeled-off to make free-standing, individual sheets, reaching up to 350 microns in length with thicknesses of only 20–100 nm. Although they are ceramics, these nanosheet materials display ductility during bending and the individual nanosheets are transparent to visible light.</p> {C24B58DB-6E77-46D5-863D-9B9F4E5448BB}http://science.energy.gov/bes/highlights/2011/bes-2011-12-a/<img src='/~/media/bes/images/highlights/2011/12/cees-thackeray-sei-layer-thumb.jpg' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>A new spectroscopic “fingerprinting” technique has been developed at a DOE user facility to identify chemical degradation products deep inside a working rechargeable battery.Mon, 18 Mar 2013 10:17:00 -0400 <p>Understanding what happens inside of rechargeable batteries is critical to making them safer and last longer. For commercially important lithium-based batteries, a new tool has been developed that uses high resolution lithium and oxygen spectroscopy to study the degradation products formed in a working battery. Inelastic x-ray scattering (IXS) measures and analyzes the energy lost by x-rays when they are scattered by light elements such as lithium; the resulting spectrum is very sensitive to the bonding and chemical structure of the atoms in the material being analyzed. Unlike traditional spectroscopic probes, IXS uses high energy x-rays that can penetrate deep inside a working battery – assessing the elemental changes at the critical solid-electrolyte interface(SEI) inside the battery. Work at Argonne National Laboratory supported by the Center for Electrical Energy Storage, a DOE Energy Research Frontier Center, is using lithium and oxygen spectra of pure, known compounds to create a catalogue of spectroscopic fingerprints of the possible decomposition productions in lithium-ion batteries. Theoretical calculations agree with the measured spectra of pure compounds, providing validation that the IXS spectra can be used to probe an unknown mixture of SEI products. Ongoing studies will use the fingerprints to determine the composition of the SEI and to decouple decomposition reactions from actual discharge products for a Li-air battery. This technique is now available to the broader battery research community at Argonne’s Advanced Photon Source.</p> {78BE572D-13E7-4977-99C6-36A4F2A19699}http://science.energy.gov/bes/highlights/2011/bes-2011-12-b/<img src='/~/media/bes/images/highlights/2011/12/emc2-abruna-track-nanocatalysts-thumb.jpg' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Researchers have captured the first three-dimensional images of changes in shape, composition, and position of individual catalyst particles during electrochemical cycling.Mon, 18 Mar 2013 10:16:59 -0400 <p>Proton exchange membrane fuel cells (PEMFCs) represent a higher efficiency and environmentally-friendly alternative to the internal combustion engine used in automobiles, but commercialization is limited due to the degradation of the cathode catalyst that is critical to fuel cell operation.  Previous work to understand catalyst degradation mechanisms after electrochemical aging involved destructive techniques that precluded making repeated observations of the same particle over time. The Energy Materials Center at Cornell (emc²), an Energy Frontier Research Center (EFRC), designed and performed experiments to use non-destructive 3-D tomographic methods to track the trajectories and morphological changes of over 300 Pt-Co nanocatalyst particles on a fuel cell carbon support as they aged during electrochemical cycling. The EFRC researchers discovered that coarsening was dominated by the movement and coalescence of the nanocatalyst particles into multicore particles rather than the result of carbon support degradation or a ripening process (larger nanoparticles growing at the expense of smaller ones). These results suggest that minimizing nanocatalyst particle movement, possibly by using functional groups on the carbon support to slow down particle movement, should extend the performance of fuel cells.</p> {4312E512-F3C4-440C-9D33-3668A3A6D307}http://science.energy.gov/bes/highlights/2011/bes-2011-12-c/<img src='/~/media/564DE5CBE1104A80A3C6BB936F063CC7.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>Laboratory measurements of “carrier multiplication” verified in real solar energy photovoltaic devices made of tiny quantum dots.Fri, 10 May 2013 11:13:33 -0400<p>Carrier multiplication (CM), also known as multiexciton generation (MEG), is a phenomenon whereby a single photon creates more than one electron-hole pair, which can boost the current in a solar cell. The development of quantum dot CM-enhanced solar cells has been frustrated by inconsistencies in measured CM efficiencies that thwart materials optimization efforts, and poor conductivity in quantum dot films that makes collection of the extra carriers inefficient. Recently, Center for Advanced Solar Photophysics (CASP) research at Los Alamos National Laboratory and the National Renewable Energy Laboratory has made key advances on both fronts. In parallel efforts, CASP spectroscopists established a rigorous and reproducible protocol for evaluating true CM efficiencies of different materials, while CASP synthesis researchers developed an effective methodology for fabricating device-grade highly conductive quantum dot films. These efforts culminated in the first exploratory solar cell to show an appreciable increase in current directly attributable to CM, in complete agreement with the spectroscopically determined efficiencies. This is a seminal achievement in the field of third-generation solar technologies, which seeks high efficiencies in low-cost devices through exploitation of novel physics such as CM.</p>{FA76C0A6-7CC8-43D2-8446-28ED3F447DF3}http://science.energy.gov/bes/highlights/2011/bes-2011-12-d/<img src='/~/media/7759C2046B074D14BDFDB00567405E75.ashx' align='left' style='height:75px;width:135px;margin-right:10px;margin-bottom:10px;'/>New insights from synchrotron-based studies are helping to assess the potential of new biofuels.Fri, 10 May 2013 11:13:34 -0400<p>Evaluation of new fuels in engines is hampered by both expense and need for large quantities of the test fuel &mdash; a problem given the limited availability for many potential biofuels. Predictive computer modeling based on quantum mechanics and chemistry promises to reduce the number of experiments needed for evaluation. To validate the fidelity of combustion chemistry models, researchers at the CEFRC conducted rigorous experimental tests of the computer predictions for combustion of butanol, an alternative fuel nearing commercialization.&nbsp;Using the Advanced Light Source, a synchrotron that generates bright beams of x-rays capable of revealing atomic and electronic structure of matter, the scientists were able to quantify the chemical species in butanol flames, including species not observable using ordinary techniques.&nbsp;While showing that the model predictions resemble the experimental data and are generally accurate, the research identified areas for improvement. Overall, the results suggest the computer modeling approach currently being developed will accelerate the evaluation of proposed fuels while reducing cost and fuel use.</p>