Batteries don’t age gracefully. The lithium ions that power portable electronics cause lingering structural damage with each cycle of charge and discharge, making devices from smartphones to tablets tick toward zero faster and faster over time. To stop or slow this steady degradation, scientists must track and tweak the imperfect chemistry of lithium-ion batteries with nanoscale precision.
In recent work at Brookhaven National Laboratory, semiconductor quantum dots (QDs) have been combined with graphene to develop nanoscale photonic devices that can dramatically improve our ability to detect light. The research has demonstrated that the thickness of the organic molecule layer that typically surrounds the QDs is crucial in attaining sufficiently high efficiency of light/energy transfer into the graphene.
Plant scientists at Brookhaven National Laboratory have found that certain enzymes responsible for desaturating fatty acids, the building blocks of oils, can link up to efficiently pass intermediate products from one enzyme to another. The research lead to the development of plants that can accumulate high levels of more healthful polyunsaturated fatty acids, or fatty acids that could be used as raw materials in place of petroleum.
Scientists at Brookhaven National Laboratory are seeking ways to synchronize the magnetic spins in nanoscale devices to build tiny yet more powerful signal-generating or receiving antennas and other electronics. Their latest work shows that stacked nanoscale magnetic vortices separated by a thin layer of copper can be driven to operate in unison, potentially producing a powerful signal that could be put to work in new electronics.
Using principles of energy transfer more commonly applied to designing solar cells, scientists at Brookhaven National Laboratory have developed a new highly sensitive way to detect specific sequences of DNA, the genetic material unique to every living thing. The method is considerably less costly than other DNA assays and has widespread potential for applications in forensics, medical diagnostics and the detection of bioterror agents.
Ever-shrinking electronic devices could get down to atomic dimensions with the help of transition metal oxides. Researchers from Cornell Univ. and Brookhaven National Laboratory have shown how to switch a particular transition metal oxide, a lanthanum nickelate (LaNiO3), from a metal to an insulator by making the material less than a nanometer thick.
Carefully timed pairs of laser pulses at the Linac Coherent Light Source have been used to trigger superconductivity in a promising copper-oxide material and immediately take x-ray snapshots of its atomic and electronic structure as superconductivity emerged. The results of this effort have pinned down a major factor behind the appearance of superconductivity, and it hinges around “stripes” of increase electrical charge.
Scientists at Brookhaven National Laboratory have made the first 3-D observations of how the structure of a lithium-ion battery anode evolves at the nanoscale in a real battery cell as it discharges and recharges. The details of this research, described in a paper published in Angewandte Chemie, could point to new ways to engineer battery materials to increase the capacity and lifetime of rechargeable batteries.
From steel beams to plastic Lego bricks, building blocks come in many materials and all sizes. Today, science has opened the way to manufacturing at the nanoscale with biological materials. Potential applications range from medicine to optoelectronic devices. In a paper published in Soft Matter, scientists announced their discovery of a 2-D crystalline structure assembled from the outer shells of a virus.
Plant growth is orchestrated by a spectrum of signals from hormones within a plant. A major group of plant hormones called cytokinins originate in the roots of plants, and their journey to growth areas on the stem and in leaves stimulates plant development. Though these phytohormones have been identified in the past, the molecular mechanism responsible for their transportation within plants was previously poorly understood. Until now.
Lithium batteries, with their exceptional ability to store power per a given weight, have been a major focus of research to enable use in everything from portable electronics to electric cars. Now researchers at Massachusetts Institute of Technology and Brookhaven National Laboratory have found a whole new avenue for such research: the use of disordered materials, which had generally been considered unsuitable for batteries.
Researchers at the U.S. Department of Energy’s Brookhaven National Laboratory report that, for the first time, a comprehensive set of tools is available for exploring correlations among the morphological, structural, electronic and chemical properties of catalytic materials under working conditions. Two recent studies have used microscopy and spectroscopy to catch custom-built catalysts in action.
New recommendations for using x-rays promise to speed investigations aimed at understanding the structure of biologically important proteins. In their study, the scientists evaluated options to remedy problems affecting data collection. Scientists who use x-ray beams to study protein crystals face a dilemma: The beams provide the best tool for understanding a protein's structure and biological function, but they often damage the crystal.
Quantum dots have potential for applications that make use of their ability to absorb or emit light and/or electric charges. Examples include more vividly colored light-emitting diodes (LEDs), photovoltaic solar cells, nanoscale transistors and biosensors. But because these applications have differing, sometimes opposite, requirements, finding ways to control the dots’ optical and electronic properties is crucial to their success.
By applying pressure to a semiconductor, researchers have been able to transform a semiconductor into a “topological insulator” (TI), an intriguing state of matter in which a material’s interior is insulating but its surfaces or edges are conducting with unique electrical properties. This is the first time that researchers have used pressure to gradually “tune” a material into the TI state.
Hydrogen is a “green” fuel that burns cleanly and can generate electricity via fuel cells. One way to sustainably produce hydrogen is by splitting water molecules using the renewable power of sunlight, but scientists are still learning how to control and optimize this reaction with catalysts. At the National Synchrotron Light Source, a research group has determined key structural information about a potential catalyst.
Sometimes big change comes from small beginnings. That’s especially true in the research of Anatoly Frenkel, a prof. of physics at Yeshiva Univ., who is working to reinvent the way we use and produce energy by unlocking the potential of some of the world’s tiniest structures: nanoparticles.
As microelectronics get smaller and smaller, one of the biggest challenges to packing a smartphone or tablet with maximum processing power and memory is the amount of heat generated by the tiny “switches” at the heart of the device. A complex metal-oxide film could help reduce the voltage required to switch electronic signals, and thus the excessive energy they require.
When it comes to designing extremely water-repellent surfaces, shape and size matter. That's the finding of a group of scientists at Brookhaven National Laboratory, who investigated the effects of differently shaped, nanoscale textures on a material's ability to force water droplets to roll off without wetting its surface.
Scientists at Brookhaven National Laboratory have developed a general approach for combining different types of nanoparticles to produce large-scale composite materials. The technique opens many opportunities for mixing and matching particles with different magnetic, optical or chemical properties to form new, multifunctional materials or materials with enhanced performance for a wide range of potential applications.
Scientists at Brookhaven National Laboratory have identified the key genes required for oil production and accumulation in plant leaves and other vegetative plant tissues. Enhancing expression of these genes resulted in vastly increased oil content in leaves, the most abundant sources of plant biomass—a finding that could have important implications for increasing the energy content of plant-based foods and renewable biofuel feedstocks.
Kids grumble about homework. But their complaints will hold no water with a group of theoretical physicists who’ve spent almost 50 years solving one homework problem: a calculation of one type of subatomic particle decay aimed at helping to answer the question of why the early universe ended up with an excess of matter. Without that excess, the matter and antimatter created in the Big Bang would have completely annihilated one another.
Carbon monoxide is a poisoning impurity in hydrogen derived from natural gas. If a catalyst could be developed that can handle this impure fuel, it could be a substantially less expensive alternative to pure hydrogen produced from water. Scientists at Brookhaven National Laboratory have used a simple, “green” process to create a new core-shell catalyst that tolerates carbon monoxide in fuel cells.
To get a better understanding of the subatomic soup that filled the early universe, and how it “froze out” to form the atoms of today’s world, scientists are taking a closer look at the nuclear phase diagram. Like a map that describes how the physical state of water morphs from solid ice to liquid to steam with changes in temperature and pressure, the nuclear phase diagram maps out different phases of the components of atomic nuclei.
Researchers at Brookhaven National Laboratory and Stony Brook Univ. have developed a way to map out the degree of "traffic congestion" on the electron highways within the photoactive layer of organic solar cells. Their new measurement and tracking technique uses optical-guided modes to help scientists better understand how the materials used in the photoactive layers influence the speed and efficiency of electron travel.