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How a Single Chemical Bond Balances Cells Between Life and Death

With SLAC's X-ray laser and synchrotron, scientists measured exactly how much energy goes into keeping a crucial chemical bond from triggering a cell's death spiral.

New Efficient, Low-Temperature Catalyst for Converting Water and CO to Hydrogen Gas and CO2

Scientists have developed a new low-temperature catalyst for producing high-purity hydrogen gas while simultaneously using up carbon monoxide (CO). The discovery could improve the performance of fuel cells that run on hydrogen fuel but can be poisoned by CO.

Study Sheds Light on How Bacterial Organelles Assemble

Scientists at Berkeley Lab and Michigan State University are providing the clearest view yet of an intact bacterial microcompartment, revealing at atomic-level resolution the structure and assembly of the organelle's protein shell. This work can help provide important information for research in bioenergy, pathogenesis, and biotechnology.

A Single Electron's Tiny Leap Sets Off 'Molecular Sunscreen' Response

In experiments at the Department of Energy's SLAC National Accelerator Laboratory, scientists were able to see the first step of a process that protects a DNA building block called thymine from sun damage: When it's hit with ultraviolet light, a single electron jumps into a slightly higher orbit around the nucleus of a single oxygen atom.

Researchers Find New Mechanism for Genome Regulation

The same mechanisms that separate mixtures of oil and water may also help the organization of an unusual part of our DNA called heterochromatin, according to a new study by Berkeley Lab researchers. They found that liquid-liquid phase separation helps heterochromatin organize large parts of the genome into specific regions of the nucleus. The work addresses a long-standing question about how DNA functions are organized in space and time, including how genes are silenced or expressed.

The Rise of Giant Viruses

Research reveals that giant viruses acquire genes piecemeal from others, with implications for bioenergy production and environmental cleanup.

Grasses: The Secrets Behind Their Success

Researchers find a grass gene affecting how plants manage water and carbon dioxide that could be useful to growing biofuel crops on marginal land.

SLAC Experiment is First to Decipher Atomic Structure of an Intact Virus with an X-ray Laser

An international team of scientists has for the first time used an X-ray free-electron laser to unravel the structure of an intact virus particle on the atomic level. The method dramatically reduces the amount of virus material required, while also allowing the investigations to be carried out several times faster than before. This opens up entirely new research opportunities.

New Perspectives Into Arctic Cloud Phases

Teamwork provides insight into complicated cloud processes that are important to potential environmental changes in the Arctic.

Illuminating a Better Way to Calculate Excitation Energy

In a new study appearing this week in The Journal of Chemical Physics, researchers demonstrate a new method to calculate excitation energies. They used a new approach based on density functional methods, which use an atom-by-atom approach to calculate electronic interactions. By analyzing a benchmark set of small molecules and oligomers, their functional produced more accurate estimates of excitation energy compared to other commonly used density functionals, while requiring less computing power.


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Chicago Quantum Exchange to Create Technologically Transformative Ecosystem

The University of Chicago is collaborating with the U.S. Department of Energy's Argonne National Laboratory and Fermi National Accelerator Laboratory to launch an intellectual hub for advancing academic, industrial and governmental efforts in the science and engineering of quantum information.

Department of Energy Awards Six Research Contracts Totaling $258 Million to Accelerate U.S. Supercomputing Technology

Today U.S. Secretary of Energy Rick Perry announced that six leading U.S. technology companies will receive funding from the Department of Energy's Exascale Computing Project (ECP) as part of its new PathForward program, accelerating the research necessary to deploy the nation's first exascale supercomputers.

Cynthia Jenks Named Director of Argonne's Chemical Sciences and Engineering Division

Argonne has named Cynthia Jenks the next director of the laboratory's Chemical Sciences and Engineering Division. Jenks currently serves as the assistant director for scientific planning and the director of the Chemical and Biological Sciences Division at Ames Laboratory.

Argonne-Developed Technology for Producing Graphene Wins TechConnect National Innovation Award

A method that significantly cuts the time and cost needed to grow graphene has won a 2017 TechConnect National Innovation Award. This is the second year in a row that a team at Argonne's Center for Nanoscale Materials has received this award.

Honeywell UOP and Argonne Seek Research Collaborations in Catalysis Under Technologist in Residence Program

Researchers at Argonne are collaborating with Honeywell UOP scientists to explore innovative energy and chemicals production.

Follow the Fantastic Voyage of the ICARUS Neutrino Detector

The ICARUS neutrino detector, born at Gran Sasso National Lab in Italy and refurbished at CERN, will make its way across the sea to Fermilab this summer. Follow along using an interactive map online.

JSA Awards Graduate Fellowships for Research at Jefferson Lab

Jefferson Sciences Associates announced today the award of eight JSA/Jefferson Lab graduate fellowships. The doctoral students will use the fellowships to support their advanced studies at their universities and conduct research at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) - a U.S. Department of Energy nuclear physics laboratory managed and operated by JSA, a joint venture between SURA and PAE Applied Technologies.

Muon Magnet's Moment Has Arrived

On May 31, the 50-foot-wide superconducting electromagnet at the center of the Muon g-2 experiment saw its first beam of muon particles from Fermilab's accelerators, kicking off a three-year effort to measure just what happens to those particles when placed in a stunningly precise magnetic field. The answer could rewrite scientists' picture of the universe and how it works.

Seven Small Businesses to Collaborate with Argonne to Solve Technical Challenges

Seven small businesses have been selected to collaborate with researchers at Argonne to address technical challenges as part of DOE's Small Business Vouchers Program.

JSA Names Charles Perdrisat and Charles Sinclair as Co-Recipients of its 2017 Outstanding Nuclear Physicist Prize

Jefferson Science Associates, LLC, announced today that Charles Perdrisat and Charles Sinclair are the recipients of the 2017 Outstanding Nuclear Physicist Prize. The 2017 JSA Outstanding Nuclear Physicist Award is jointly awarded to Charles Perdrisat for his pioneering implementation of the polarization transfer technique to determine proton elastic form factors, and to Charles Sinclair for his crucial development of polarized electron beam technology, which made such measurements, and many others, possible.


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Oxygen: The Jekyll and Hyde of Biofuels

Scientists are devising ways to protect plants, biofuels and, ultimately, the atmosphere itself from damage caused by an element that sustains life on earth.

The Rise of Giant Viruses

Research reveals that giant viruses acquire genes piecemeal from others, with implications for bioenergy production and environmental cleanup.

Grasses: The Secrets Behind Their Success

Researchers find a grass gene affecting how plants manage water and carbon dioxide that could be useful to growing biofuel crops on marginal land.

New Perspectives Into Arctic Cloud Phases

Teamwork provides insight into complicated cloud processes that are important to potential environmental changes in the Arctic.

Mountaintop Plants and Soils to Become Out of Sync

Plants and soil microbes may be altered by climate warming at different rates and in different ways, meaning vital nutrient patterns could be misaligned.

If a Tree Falls in the Amazon

For the first time, scientists pinpointed how often storms topple trees, helping to predict how changes in Amazonia affect the world.

Turning Waste into Fuels, Microbial Style

A newly discovered metabolic process linking different bacteria in a community could enhance bioenergy production.

Department of Energy Awards Six Research Contracts Totaling $258 Million to Accelerate U.S. Supercomputing Technology

Today U.S. Secretary of Energy Rick Perry announced that six leading U.S. technology companies will receive funding from the Department of Energy's Exascale Computing Project (ECP) as part of its new PathForward program, accelerating the research necessary to deploy the nation's first exascale supercomputers.

Electrifying Magnetism

Researchers create materials with controllable electrical and magnetic properties, even at room temperature.

One Step Closer to Practical Fast Charging Batteries

Novel electrode materials have designed pathways for electrons and ions during the charge/discharge cycle.


Chemical "Dance" of Cobalt Catalysis Could Pave Way to Solar Fuels

Article ID: 675858

Released: 2017-06-02 16:05:49

Source Newsroom: Argonne National Laboratory

  • Credit: Argonne National Laboratory

    Argonne chemists Dugan Hayes, Lin Chen, and Ryan Hadt have identified a rapid electronic process that could aid the water-splitting reaction in cobalt-containing catalysts. Cobalt catalysts are relatively inexpensive and could replace more expensive precious metal catalysts in the production of clean energy, most notably solar fuels.

  • Credit: Argonne National Laboratory

    Argonne chemists Dugan Hayes, Lin Chen, and Ryan Hadt have identified a rapid electronic process that could aid the water-splitting reaction in cobalt-containing catalysts. Cobalt catalysts are relatively inexpensive and could replace more expensive precious metal catalysts in the production of clean energy, most notably solar fuels.

  • Credit: Argonne National Laboratory

    Argonne chemists Dugan Hayes, Lin Chen, and Ryan Hadt have identified a rapid electronic process that could aid the water-splitting reaction in cobalt-containing catalysts. Cobalt catalysts are relatively inexpensive and could replace more expensive precious metal catalysts in the production of clean energy, most notably solar fuels.

  • Credit: Argonne National Laboratory

    Argonne chemists Dugan Hayes, Lin Chen, and Ryan Hadt have identified a rapid electronic process that could aid the water-splitting reaction in cobalt-containing catalysts. Cobalt catalysts are relatively inexpensive and could replace more expensive precious metal catalysts in the production of clean energy, most notably solar fuels.

  • Credit: Argonne National Laboratory

    Argonne chemists Dugan Hayes, Lin Chen, and Ryan Hadt have identified a rapid electronic process that could aid the water-splitting reaction in cobalt-containing catalysts. Cobalt catalysts are relatively inexpensive and could replace more expensive precious metal catalysts in the production of clean energy, most notably solar fuels.

By splitting a water molecule into two atoms of hydrogen and one of oxygen, scientists can use the boundless energy of the sun to make a clean fuel. In a new study from the U.S. Department of Energy’s (DOE) Argonne National Laboratory and Harvard University, scientists have for the first time been able to see an especially important step in the water-splitting process, which may bring us closer to abundant solar energy for all.

Splitting a water molecule requires a metal catalyst to get the reaction going. Recently, much scientific attention has focused on cobalt, a relatively abundant and inexpensive catalyst that – in the right circumstances – can serve as an escort to an electronic dance between hydrogens and oxygens.

“Essentially, it allows you to have a focused snapshot, as opposed to just seeing a chemical blur. It’s important that we determine the characteristics of the catalyst on the timescale the electrons are moving.”

“Cobalt oxygen-evolving catalysts are the active components in technologies like artificial leaves and other materials in which you can harvest light to drive the synthesis of solar fuels,” said Argonne postdoctoral researcher Ryan Hadt, a co-first author of the study.

The overall water-splitting reaction actually has two halves. The researchers focused on the first half, called water oxidation, which requires the transfer of four protons and four electrons and eventually results in the formation of an oxygen-oxygen bond. For this process, the oxygens need a temporary dance partner, which is played by the cobalt catalyst.

But the reason this dance isn’t yet well understood is that the transfers and the formation of the bond happen in a flash – the whole process takes less than a billionth of a second. To understand the nuances of the bonding action, the researchers needed to perform X-ray absorption spectroscopy measurements at Argonne’s Advanced Photon Source.

In their analysis, the researchers focused on a particularly intriguing chemical twist.  At the beginning of the process, a bridge of two oxygen atoms connects two cobalt ions. Each of the cobalt ions, in turn, is connected to its own water molecule. At this point, things are pretty stable.

The electronic dance is ready to begin when a cobalt ion adds an additional positive charge, temporarily increasing a characteristic number that scientists term an “oxidation state.” In the case of cobalt, the oxidation state changes, just for an instant, from three to four.

When two cobalt ions with an oxidation state of four come into contact, the process begins in earnest. The charge transfers cause the hydrogen atoms of the water molecules to dissociate from their oxygen bonds, leaving the cobalt atoms bonded just to oxygen ions.

The key moment follows immediately afterwards, when the cobalt centers each receive an extra electron from the newly exposed oxygen atoms. When this happens, a bond is formed between the two oxygens, creating a molecular intermediate stage called a peroxide, which can be rapidly oxidized to release a dioxygen molecule. The electrons obtained from water during this process can be used to make solar fuels.

By using the Advanced Photon Source, a DOE Office of Science User Facility, the researchers were able to directly measure cobalt oxidation states and then use theory to a calculate a quantity known as “exchange coupling,” a quantum mechanical value that identifies the relationship between the spins of the electrons that are shuttled between the oxygen and cobalt atoms. The researchers found that these electrons spins are in opposite directions – in scientific parlance, they are antiferromagnetically coupled. 

“Antiferromagnetism plays an important role in the formation of the oxygen-oxygen bond,” said Hadt, “as it provides a way to simultaneously transfer two electrons to make a chemical bond.”

Argonne postdoctoral researcher and study author Dugan Hayes also pointed to the unique ability of the Advanced Photon Source to resolve the location of the extra-oxidized cobalt atoms. “Essentially, it allows you to have a focused snapshot, as opposed to just seeing a chemical blur,” he said. “It’s important that we determine the characteristics of the catalyst on the timescale the electrons are moving.”

A paper based on the research, “In situ characterization of cofacial Co(IV) centers in Co4O4 cubane: Modeling the high-valent active site in oxygen-evolving catalysts,” appeared in the March 27 edition of the Proceedings of the National Academy of Sciences.

The research was funded by DOE’s Office of Science. Other authors of the study include Argonne’s Lin Chen and Benjamin Reinhardt and several members of the Nocera group at Harvard University.

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation's first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America's scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy's Office of Science.

The U.S. Department of Energy's Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit the Office of Science website.