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Printed, Flexible and Rechargeable Battery Can Power Wearable Sensors

Nanoengineers at the University of California San Diego have developed the first printed battery that is flexible, stretchable and rechargeable. The zinc batteries could be used to power everything from wearable sensors to solar cells and other kinds of electronics. The work appears in the April 19, 2017 issue of Advanced Energy Materials.

Neutrons Provide the First Nanoscale Look at a Living Cell Membrane

A research team from the Department of Energy's Oak Ridge National Laboratory has performed the first-ever direct nanoscale examination of a living cell membrane. In doing so, it also resolved a long-standing debate by identifying tiny groupings of lipid molecules that are likely key to the cell's functioning.

How X-Rays Helped to Solve Mystery of Floating Rocks

Experiments at Berkeley Lab's Advanced Light Source have helped scientists to solve a mystery of why some rocks can float for years in the ocean, traveling thousands of miles before sinking.

Special X-Ray Technique Allows Scientists to See 3-D Deformations

In a new study published last Friday in Science, researchers at Argonne used an X-ray scattering technique called Bragg coherent diffraction imaging to reconstruct in 3-D the size and shape of grain defects. These defects create imperfections in the lattice of atoms inside a grain that can give rise to interesting material properties and effects.

Neptune: Neutralizer-Free Plasma Propulsion

The most established plasma propulsion concepts are gridded-ion thrusters that accelerate and emit a larger number of positively charged particles than those that are negatively charged. To enable the spacecraft to remain charge-neutral, a "neutralizer" is used to inject electrons to exactly balance the positive ion charge in the exhaust beam. However, the neutralizer requires additional power from the spacecraft and increases the size and weight of the propulsion system. Researchers are investigating how the radio-frequency self-bias effect can be used to remove the neutralizer altogether, and they report their work in this week's Physics of Plasmas.

Report Sheds New Insights on the Spin Dynamics of a Material Candidate for Low-Power Devices

In a report published in Nano LettersArgonne researchers reveal new insights into the properties of a magnetic insulator that is a candidate for low-power device applications; their insights form early stepping-stones towards developing high-speed, low-power electronics that use electron spin rather than charge to carry information.

Researchers Find Computer Code That Volkswagen Used to Cheat Emissions Tests

An international team of researchers has uncovered the mechanism that allowed Volkswagen to circumvent U.S. and European emission tests over at least six years before the Environmental Protection Agency put the company on notice in 2015 for violating the Clean Air Act. During a year-long investigation, researchers found code that allowed a car's onboard computer to determine that the vehicle was undergoing an emissions test.

Physicists Discover That Lithium Oxide on Tokamak Walls Can Improve Plasma Performance

A team of physicists has found that a coating of lithium oxide on the inside of fusion machines known as tokamaks can absorb as much deuterium as pure lithium can.

Scientists Perform First Basic Physics Simulation of Spontaneous Transition of the Edge of Fusion Plasma to Crucial High-Confinement Mode

PPPL physicists have simulated the spontaneous transition of turbulence at the edge of a fusion plasma to the high-confinement mode that sustains fusion reactions. The research was achieved with the extreme-scale plasma turbulence code XGC developed at PPPL in collaboration with a nationwide team.

Green Fleet Technology

New research at Penn State addresses the impact delivery trucks have on the environment by providing green solutions that keep costs down without sacrificing efficiency.


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Rensselaer Polytechnic Institute Graduates Urged to Embrace Change at 211th Commencement

Describing the dizzying pace of technological innovation, former United States Secretary of Energy Ernest J. Moniz urged graduates to "anticipate career change, welcome it, and manage it to your and your society's benefit" at the 211th Commencement at Rensselaer Polytechnic Institute (RPI) Saturday.

ORNL Welcomes Innovation Crossroads Entrepreneurial Research Fellows

Oak Ridge National Laboratory today welcomed the first cohort of innovators to join Innovation Crossroads, the Southeast region's first entrepreneurial research and development program based at a U.S. Department of Energy national laboratory.

Department of Energy Secretary Recognizes Argonne Scientists' Work to Fight Ebola, Cancer

Two groups of researchers at Argonne earned special awards from the office of the U.S. Secretary of Energy for addressing the global health challenges of Ebola and cancer.

Jefferson Science Associates, LLC Recognized for Leadership in Small Business Utilization

Jefferson Lab/Jefferson Science Associates has a long-standing commitment to doing business with and mentoring small businesses. That commitment and support received national recognition at the 16th Annual Dept. of Energy Small Business Forum and Expo held May 16-18, 2017 in Kansas City, Mo.

Rensselaer Polytechnic Institute President's Commencement Colloquy to Address "Criticality, Incisiveness, Creativity"

To kick off the Rensselaer Polytechnic Institute Commencement weekend, the annual President's Commencement Colloquy will take place on Friday, May 19, beginning at 3:30 p.m. The discussion, titled "Criticality, Incisiveness, Creativity," will include the Honorable Ernest J. Moniz, former Secretary of Energy, and the Honorable Roger W. Ferguson Jr., President and CEO of TIAA, and will be moderated by Rensselaer President Shirley Ann Jackson.

ORNL, University of Tennessee Launch New Doctoral Program in Data Science

The Tennessee Higher Education Commission has approved a new doctoral program in data science and engineering as part of the Bredesen Center for Interdisciplinary Research and Graduate Education.

SurfTec Receives $1.2 Million Energy Award to Develop Novel Coating

The Department of Energy has awarded $1.2 million to SurfTec LLC, a company affiliated with the U of A Technology Development Foundation, to continue developing a nanoparticle-based coating to replace lead-based journal bearings in the next generation of electric machines.

Ames Laboratory Scientist Inducted Into National Inventors Hall of Fame

Iver Anderson, senior metallurgist at Ames Laboratory, has been inducted into the National Inventors Hall of Fame.

DOE HPC4Mfg Program Funds 13 New Projects to Improve U.S. Energy Technologies Through High Performance Computing

A U.S. Department of Energy (DOE) program designed to spur the use of high performance supercomputers to advance U.S. manufacturing is funding 13 new industry projects for a total of $3.9 million.

Penn State Wind Energy Club Breezes to Victory in Collegiate Wind Competition

The Penn State Wind Energy Club breezed through the field at the U.S. Department of Energy Collegiate Wind Competition 2017 Technical Challenge, held April 20-22 at the National Wind Technology Center near Boulder, Colorado--earning its third overall victory in four years at the Collegiate Wind Competition.


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Casting a Wide Net

Designed molecules will provide positive impacts in energy production by selectively removing unwanted ions from complex solutions.

New Software Tools Streamline DNA Sequence Design-and-Build Process

Enhanced software tools will accelerate gene discovery and characterization, vital for new forms of fuel production.

The Ultrafast Interplay Between Molecules and Materials

Computer calculations by the Center for Solar Fuels, an Energy Frontier Research Center, shed light on nebulous interactions in semiconductors relevant to dye-sensitized solar cells.

Supercapacitors: WOODn't That Be Nice

Researchers at Nanostructures for Electrical Energy Storage, an Energy Frontier Research Center, take advantage of nature-made materials and structure for energy storage research.

Groundwater Flow Is Key for Modeling the Global Water Cycle

Water table depth and groundwater flow are vital to understanding the amount of water that plants transmit to the atmosphere.

Finding the Correct Path

A new computational technique greatly simplifies the complex reaction networks common to catalysis and combustion fields.

Opening Efficient Routes to Everyday Plastics

A new material from the Inorganometallic Catalyst Design Center, an Energy Frontier Research Center, facilitates the production of key industrial supplies.

Fight to the Top: Silver and Gold Compete for the Surface of a Bimetallic Solid

It's the classic plot of a buddy movie. Two struggling bodies team up to drive the plot and do good together. That same idea, when it comes to metals, could help scientists solve a big problem: the amount of energy consumed by making chemicals.

Saving Energy Through Light Control

New materials, designed by researchers at the Center for Excitonics, an Energy Frontier Research Center, can reduce energy consumption with the flip of a switch.

Teaching Perovskites to Swim

Scientists at the ANSER Energy Frontier Research Center designed a two-component layer protects a sunlight-harvesting device from water and heat.


Saturday May 20, 2017, 12:05 PM

Rensselaer Polytechnic Institute Graduates Urged to Embrace Change at 211th Commencement

Rensselaer Polytechnic Institute (RPI)

Monday May 15, 2017, 01:05 PM

ORNL, University of Tennessee Launch New Doctoral Program in Data Science

Oak Ridge National Laboratory

Friday April 07, 2017, 11:05 AM

Champions in Science: Profile of Jonathan Kirzner

Department of Energy, Office of Science

Wednesday April 05, 2017, 12:05 PM

High-Schooler Solves College-Level Security Puzzle From Argonne, Sparks Interest in Career

Argonne National Laboratory

Tuesday March 28, 2017, 12:05 PM

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Great Neck South High School Wins Regional Science Bowl at Brookhaven Lab

Brookhaven National Laboratory

Wednesday February 15, 2017, 04:05 PM

Middle Schoolers Test Their Knowledge at Science Bowl Competition

Argonne National Laboratory

Friday January 27, 2017, 04:00 PM

Haslam Visits ORNL to Highlight State's Role in Discovering Tennessine

Oak Ridge National Laboratory

Tuesday November 08, 2016, 12:05 PM

Internship Program Helps Foster Development of Future Nuclear Scientists

Oak Ridge National Laboratory

Friday May 13, 2016, 04:05 PM

More Than 12,000 Explore Jefferson Lab During April 30 Open House

Thomas Jefferson National Accelerator Facility

Monday April 25, 2016, 05:05 PM

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Ames Laboratory

Friday March 25, 2016, 12:05 PM

NMSU Undergrad Tackles 3D Particle Scattering Animations After Receiving JSA Research Assistantship

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Shannon Greco: A Self-Described "STEM Education Zealot"

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University of Utah Makes Solar Accessible

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Texas Tech Energy Commerce Students, Community Light up Tent City

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Wednesday November 23, 2011, 10:45 AM

Don't Get 'Frosted' Over Heating Your Home This Winter

Temple University

Wednesday July 06, 2011, 06:00 PM

New Research Center To Tackle Critical Challenges Related to Aircraft Design, Wind Energy, Smart Buildings

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Friday April 22, 2011, 09:00 AM

First Polymer Solar-Thermal Device Heats Home, Saves Money

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Thursday February 10, 2011, 05:00 PM

ARRA Grant to Help Fund Seminary Building Green Roof

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Tuesday December 07, 2010, 05:00 PM

UC San Diego Installing 2.8 Megawatt Fuel Cell to Anchor Energy Innovation Park

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Monday November 01, 2010, 12:50 PM

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Friday September 10, 2010, 12:40 PM

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Fight to the Top: Silver and Gold Compete for the Surface of a Bimetallic Solid

Article ID: 673966

Released: 2017-05-02 11:05:04

Source Newsroom: Department of Energy, Office of Science

  • Credit: Image: Nathan Johnson, Pacific Northwest National Lab

    Silver atoms migrate in an alloy, changing the material’s structure and reactivity as they do so. Understanding the changes is key to creating more energy-efficient catalysts

  • Credit: Image: Nicholas Gould, CCEI EFRC

    An alloy surface forms reactive oxygen. (Au): Gold, (Ag): Silver, (O): Oxygen.

  • Credit: Image: Nicholas Gould, CCEI EFRC

    (A) Low-magnification image of the alloy during ozone treatment. (B) Increased magnification image of an oxygen-rich layer formed during ozone treatment.

  • Credit: Image: Nicholas Gould, CCEI EFRC

    (A) Low-magnification image of the alloy shortly after methanol treatment. (B) Increased magnification image of the removal of the oxygen-rich surface in the previous figure (right), and the formation of gold-rich particles (red square).

It’s the classic plot of a buddy movie. Two struggling bodies team up to drive the plot and do good together. That same idea, when it comes to metals, could help scientists solve a big problem: the amount of energy consumed by making chemicals.

Before delving into the intricacies of the chemistry in question, an introduction to alloys and their uses is beneficial. An alloy is a mixture of metals that often has properties superior to the sum of its parts. For example, stainless steel is an alloy of mostly iron and chromium, and the mixture has the strength of iron and the corrosion resistance of chromium, yielding a symbiotic solid solution. Alloys are commonly used as catalysts to accelerate a chemical reaction to form valuable products.

The transformation of methanol (CH3OH) to methyl formate (C2H4O2) is important for industrial production of chemicals critical to modern life, such as formamides and formic acid, which are precursors to pharmaceuticals and agricultural herbicides and pesticides. These chemicals are produced on such a large scale that improvement in reaction efficiency would result in significant energy savings and reduced environmental impact.

However, the reaction is tricky. Oxygen in the air we breathe cannot react with methanol to create formate, because it exists as a pair of oxygen atoms. But most metal surfaces can break oxygen-oxygen bonds to form oxygen atoms that are reactive, the exception being pure gold. Yet a gold-silver alloy has unusual properties, including creation of gold-oxygen bonds that pure gold cannot form. This is a similar phenomenon to formation of rust on iron surfaces, where rust is simply iron-oxygen bonds.

Recently, researchers at the Integrated Mesoscale Architectures for Sustainable Catalysis, an Energy Frontier Research Center, investigated a gold-and-silver alloy for turning methanol into methyl formate. The material is highly porous, which gives it a high contact area with any gases flowing through it. However, the material has surprisingly dynamic properties, and as the alloy is exposed to different gas streams, the positions of gold and silver atoms rearrange. Some arrangements led to the desired methyl formate, while others led to valueless carbon dioxide. The challenge is to understand how the alloy restructures during the reaction, and how to maintain the desired configuration. Initially, the catalyst had to be treated with gaseous flowing ozone, O3 (three oxygens bonded together), to form the desired structure.

The team examined the alloy using high-resolution microscopy at Brookhaven National Laboratory and X-ray photoelectron spectroscopy at Lawrence Berkeley National Laboratory. By looking closely and probing only the first few layers of the material, the team identified the structure responsible for methyl formate production. They discovered that silver-and-gold alloys, enriched in silver (greater than the overall 3 percent), catalyze methanol conversion to methyl formate. During ozone treatment, the silver atoms are enriched on the surface. In other words, silver atoms inside the metal alloy reacted with ozone and migrated towards the surface to form silver-oxygen and gold-oxygen bonds.

When the feed is switched from ozone to methanol, the methanol reacts with the surface oxygen. Initially, the methanol reacts to carbon dioxide, but after the surface oxygen is depleted, the methanol converts to valuable methyl formate. Surprisingly, as the oxygen is consumed, silver migrates into the subsurface — a few layers of atoms below the surface — forming a local surface alloy. This structural change coincided with the formation of a new oxygen species and the production of methyl formate. Thus, at this point, the alloy was in an optimal structure to create methyl formate.

However, further exposure to methanol removed the oxygen responsible for methyl formate production and caused further, detrimental rearrangements of the silver and gold atoms. Fortunately, the team found that supplementing the methanol feed with oxygen allowed for the continual regeneration of the valuable oxygen species responsible for formate production. Thus, a key factor for maintaining the methyl formate production is to keep the subsurface silver alloy structure from rearranging. The team prevented the alloy from restructuring by using the right operating temperature and oxygen content in the methanol stream.

The novelty of this work lies in its observations of the catalyst behavior during the reaction. The work demonstrates the dynamic nature of the catalyst and shows that the products are sensitive to the catalyst structure. The knowledge of how catalysts restructure during the reaction will lead to using the proper conditions and, ultimately, lower costs and environmental impact for commodity chemical production.

Acknowledgments: 

This work was supported as part of the Integrated Mesoscale Architectures for Sustainable Catalysis, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences. Work at Lawrence Livermore National Laboratory was performed under the auspices of the U.S. Department of Energy. This research used resources of the Center for Functional Nanomaterials, a U.S. Department of Energy Office of Science user facility. It also used resources of the Advanced Light Source, a U.S. Department of Energy Office of Science user facility.

More Information: 

Zugic B, L Wang, C Heine, DN Zakharov, BAJ Lechner, EA Stach, J Biener, M Salmeron, RJ Madix, and CM Friend. 2016. “Dynamic Restructuring Drives Catalytic Activity on Nanoporous Gold-Silver Alloy Catalysts.” Nature Materials 1(December):1-8. DOI: 10.1038/nmat4824

This item, written by Nicholas Gould, is part of Frontiers in Energy Research, a newsletter for the Energy Frontier Research Centers created by early career members of the centers. See http://www.energyfrontier.us/newsletter/