Scientists claim breakthrough

in antimatter hunt

November 19, 2010
Photo released by CERN on November 18, 2010 shows an image taken by the ALPHA annihilation detector showing untrapped antihydrogen atoms annihilating on the inner surface of the ALPHA trap.Photo released by CERN on November 18, 2010 shows an image taken by the ALPHA annihilation detector showing untrapped antihydrogen atoms annihilating on the inner surface of the ALPHA trap. Photo: AP/CERN

Scientists claimed a breakthrough Thursday toward solving one of the biggest riddles of physics, trapping an “anti-atom” for the first time in a quest to understand what happened to all the antimatter that has vanished since the Big Bang.

An international team of physicists at the European Organisation for Nuclear Research, or CERN, managed to keep atoms of anti-hydrogen from disappearing long enough to demonstrate that they can be studied in the lab.

“For us it’s a big breakthrough because it means we can take the next step, which is to try to compare matter and antimatter,” the team’s spokesman, American scientist Jeffrey Hangst, said Thursday.

“This field is 20 years old and has been making incremental progress toward exactly this all along the way,” he added. “We really think that this was the most difficult step.”

Researchers have puzzled for decades over why antimatter seems to have disappeared from the universe.

Theory posits that matter and its opposite, antimatter — both are defined as having mass and taking up space — were created in equal amounts at the moment of the Big Bang, which spawned the universe some 13.7 billion years ago. While matter went on to become the building block of everything that exists, antimatter has all but disappeared except in the lab.

Hangst and his colleagues, who included scientists from Britain, Brazil, Canada, Israel and the United States, trapped 38 anti-hydrogen atoms individually for more than one tenth of a second, according to a paper published online Wednesday by the journal Nature.

Since their first success, the team has managed to hold the anti-atoms even longer.

“Unfortunately I can’t tell you how long, because we haven’t published the number yet,” Hangst said. “But I can tell you that it’s much, much longer than a tenth of a second. Within human comprehension on a real clock.”

Scientists have long been able to create individual particles of antimatter such as anti-protons, anti-neutrons and positrons — the opposite of electrons. Since 2002, they have also managed to create anti-atoms in large quantities, but until recently none could be trapped for long enough to study them, because atoms made of antimatter and matter annihilate each other in a burst of energy upon contact.

“It doesn’t help if they disappear immediately upon their creation,” said Hangst. “So the big goal has been to hold onto them.”

Two teams had been competing for that goal at CERN, the world’s largest physics lab best known for its $US10 billion smasher, the Large Hadron Collider. The collider, built deep under the Swiss-French border, wasn’t used for this experiment.

Hangst’s ALPHA team got there first, beating the rival ATRAP team led by Harvard physicist Gerald Gabrielse, who nevertheless welcomed the result.

“The atoms that were trapped were not yet trapped very long and in a very usable number, but one has to crawl before you sprint,” he said.

Many new techniques painstakingly developed over five years of experimental trial and error preceded the successful capture of anti-hydrogen.

To trap the anti-atoms inside an electromagnetic field and to stop them from annihilating atoms, researchers had to create anti-hydrogen at temperatures less than half a degree above absolute zero.

“Think of it as a marble rolling back and forth in a bowl,” said Hangst. “If the marble is rolling too fast (i.e. the anti-atom is too hot) it just goes over the edge.”

Next, scientists plan to conduct basic experiments on the anti-atom, such as shining a laser onto it and seeing how it behaves, he said.

“We have a chance to make a really precise comparison between a matter system and an antimatter system,” he said, “That’s unique, that’s never been done. That’s where we’re headed now.”

Hangst downplayed speculation that antimatter might someday be harnessed as a source of energy, or to create a powerful weapon, an idea popularised in Dan Brown’s best-selling novel “Angels and Demons”.

“It would take longer than the age of the universe to make one gram of antimatter,” he said, calling the process “a losing proposition because it takes much more energy to make antimatter than you get out of it.”

Sourced & published by Henry Sapiecha

Renewable Energy:

Inexpensive Metal Catalyst

Can Effectively Generate

Hydrogen from Water

Science (May 1, 2010) — Hydrogen would command a key role in future renewable energy technologies, experts agree, if a relatively cheap, efficient and carbon-neutral means of producing it can be developed. An important step towards this elusive goal has been taken by a team of researchers with the U.S. Department of Energy’s (DOE) Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California, Berkeley. The team has discovered an inexpensive metal catalyst that can effectively generate hydrogen gas from water.


“Our new proton reduction catalyst is based on a molybdenum-oxo metal complex that is about 70 times cheaper than platinum, today’s most widely used metal catalyst for splitting the water molecule,” said Hemamala Karunadasa, one of the co-discoverers of this complex. “In addition, our catalyst does not require organic additives, and can operate in neutral water, even if it is dirty, and can operate in sea water, the most abundant source of hydrogen on earth and a natural electrolyte. These qualities make our catalyst ideal for renewable energy and sustainable chemistry.”

Karunadasa holds joint appointments with Berkeley Lab’s Chemical Sciences Division and UC Berkeley’s Chemistry Department. She is the lead author of a paper describing this work that appears in the April 29, 2010 issue of the journal Nature, titled “A molecular molybdenum-oxo catalyst for generating hydrogen from water.” Co-authors of this paper were Christopher Chang and Jeffrey Long, who also hold joint appointments with Berkeley Lab and UC Berkeley. Chang, in addition, is also an investigator with the Howard Hughes Medical Institute (HHMI).

Hydrogen gas, whether combusted or used in fuel cells to generate electricity, emits only water vapor as an exhaust product, which is why this nation would already be rolling towards a hydrogen economy if only there were hydrogen wells to tap. However, hydrogen gas does not occur naturally and has to be produced. Most of the hydrogen gas in the United States today comes from natural gas, a fossil fuel. While inexpensive, this technique adds huge volumes of carbon emissions to the atmosphere. Hydrogen can also be produced through the electrolysis of water — using electricity to split molecules of water into molecules of hydrogen and oxygen. This is an environmentally clean and sustainable method of production — especially if the electricity is generated via a renewable technology such as solar or wind — but requires a water-splitting catalyst.

Nature has developed extremely efficient water-splitting enzymes — called hydrogenases — for use by plants during photosynthesis, however, these enzymes are highly unstable and easily deactivated when removed from their native environment. Human activities demand a stable metal catalyst that can operate under non-biological settings.

Metal catalysts are commercially available, but they are low valence precious metals whose high costs make their widespread use prohibitive. For example, platinum, the best of them, costs some $2,000 an ounce.

“The basic scientific challenge has been to create earth-abundant molecular systems that produce hydrogen from water with high catalytic activity and stability,” Chang says. “We believe our discovery of a molecular molybdenum-oxo catalyst for generating hydrogen from water without the use of additional acids or organic co-solvents establishes a new chemical paradigm for creating reduction catalysts that are highly active and robust in aqueous media.”

The molybdenum-oxo complex that Karunadasa, Chang and Long discovered is a high valence metal with the chemical name of (PY5Me2)Mo-oxo. In their studies, the research team found that this complex catalyzes the generation of hydrogen from neutral buffered water or even sea water with a turnover frequency of 2.4 moles of hydrogen per mole of catalyst per second.

Long says, “This metal-oxo complex represents a distinct molecular motif for reduction catalysis that has high activity and stability in water. We are now focused on modifying the PY5Me ligand portion of the complex and investigating other metal complexes based on similar ligand platforms to further facilitate electrical charge-driven as well as light-driven catalytic processes. Our particular emphasis is on chemistry relevant to sustainable energy cycles.”

This research was supported in part by the DOE Office of Science through Berkeley Lab’s Helios Solar Energy Research Center, and in part by a grant from the National science Foundation.

Sourced and published by Henry Sapiecha 2nd May 2010

Viruses Harnessed to Split Water

ScienceDaily (Apr. 12, 2010) — A team of MIT researchers has found a novel way to mimic the process by which plants use the power of sunlight to split water and make chemical fuel to power their growth. In this case, the team used a modified virus as a kind of biological scaffold that can assemble the nanoscale components needed to split a water molecule into hydrogen and oxygen atoms.


Splitting water is one way to solve the basic problem of solar energy: It’s only available when the sun shines. By using sunlight to make hydrogen from water, the hydrogen can then be stored and used at any time to generate electricity using a fuel cell, or to make liquid fuels (or be used directly) for cars and trucks.

Other researchers have made systems that use electricity, which can be provided by solar panels, to split water molecules, but the new biologically based system skips the intermediate steps and uses sunlight to power the reaction directly. The advance is described in a paper published on April 11 in Nature Nanotechnology.

The team, led by Angela Belcher, the Germeshausen Professor of Materials Science and Engineering and Biological Engineering, engineered a common, harmless bacterial virus called M13 so that it would attract and bind with molecules of a catalyst (the team used iridium oxide) and a biological pigment (zinc porphyrins). The viruses became wire-like devices that could very efficiently split the oxygen from water molecules.

Over time, however, the virus-wires would clump together and lose their effectiveness, so the researchers added an extra step: encapsulating them in a microgel matrix, so they maintained their uniform arrangement and kept their stability and efficiency.

While hydrogen obtained from water is the gas that would be used as a fuel, the splitting of oxygen from water is the more technically challenging “half-reaction” in the process, Belcher explains, so her team focused on this part. Plants and cyanobacteria (also called blue-green algae), she says, “have evolved highly organized photosynthetic systems for the efficient oxidation of water.” Other researchers have tried to use the photosynthetic parts of plants directly for harnessing sunlight, but these materials can have structural stability issues.

Belcher decided that instead of borrowing plants’ components, she would borrow their methods. In plant cells, natural pigments are used to absorb sunlight, while catalysts then promote the water-splitting reaction. That’s the process Belcher and her team, including doctoral student Yoon Sung Nam, the lead author of the new paper, decided to imitate.

In the team’s system, the viruses simply act as a kind of scaffolding, causing the pigments and catalysts to line up with the right kind of spacing to trigger the water-splitting reaction. The role of the pigments is “to act as an antenna to capture the light,” Belcher explains, “and then transfer the energy down the length of the virus, like a wire. The virus is a very efficient harvester of light, with these porphyrins attached.

“We use components people have used before,” she adds, “but we use biology to organize them for us, so you get better efficiency.”

Using the virus to make the system assemble itself improves the efficiency of the oxygen production fourfold, Nam says. The researchers hope to find a similar biologically based system to perform the other half of the process, the production of hydrogen. Currently, the hydrogen atoms from the water get split into their component protons and electrons; a second part of the system, now being developed, would combine these back into hydrogen atoms and molecules. The team is also working to find a more commonplace, less-expensive material for the catalyst, to replace the relatively rare and costly iridium used in this proof-of-concept study.

Thomas Mallouk, the DuPont Professor of Materials Chemistry and Physics at Pennsylvania State University, who was not involved in this work, says, “This is an extremely clever piece of work that addresses one of the most difficult problems in artificial photosynthesis, namely, the nanoscale organization of the components in order to control electron transfer rates.”

He adds: “There is a daunting combination of problems to be solved before this or any other artificial photosynthetic system could actually be useful for energy conversion.” To be cost-competitive with other approaches to solar power, he says, the system would need to be at least 10 times more efficient than natural photosynthesis, be able to repeat the reaction a billion times, and use less expensive materials. “This is unlikely to happen in the near future,” he says. “Nevertheless, the design idea illustrated in this paper could ultimately help with an important piece of the puzzle.”

Belcher will not even speculate about how long it might take to develop this into a commercial product, but she says that within two years she expects to have a prototype device that can carry out the whole process of splitting water into oxygen and hydrogen, using a self-sustaining and durable system.

Funding was provided by he Italian energy company Eni, through the MIT Energy Initiative (MITEI)

Sourced and published by Henry Sapiecha 14th April 2010

Blueprint for ‘Artificial Leaf’

Mimics Mother Nature and helps to

turn water to hydrogen for fuel

ScienceDaily (Mar. 26, 2010) — Scientists have presented a design strategy to produce the long-sought artificial leaf, which could harness Mother Nature’s ability to produce energy from sunlight and water in the process called photosynthesis. The new recipe, based on the chemistry and biology of natural leaves, could lead to working prototypes of an artificial leaf that capture solar energy and use it efficiently to change water into hydrogen fuel, they stated.


Their report was scheduled for the 239th National Meeting of the American Chemical Society (ACS) in San Francisco. It was among more than 12,000 scientific reports scheduled for presentation at the meeting, one of the largest scientific gatherings of 2010.

“This concept may provide a new vista for the design of artificial photosynthetic systems based on biological paradigms and build a working prototype to exploit sustainable energy resources,” Tongxiang Fan, Ph.D. and colleagues Di Zhang, Ph.D. and Han Zhou, Ph.D., reported, They are with the State Key Lab of Matrix Composites at Shanghai Jiaotong University, Shanghai, China.

Fan pointed out that using sunlight to split water into its components, hydrogen and oxygen, is one of the most promising and sustainable tactics to escape current dependence on coal, oil, and other traditional fuels. When burned, those fuels release carbon dioxide, the main greenhouse gas. Combustion of hydrogen, in contrast, forms just water vapor. That appeal is central to the much-discussed “Hydrogen Economy,” and some auto companies, such as Toyota, have developed hydrogen-fueled cars. Lacking, however, is a cost-effective sustainable way to produce hydrogen.

With that in mind, Fan and co-workers decided to take a closer look at the leaf, nature’s photosynthetic system, with plans to use its structure as a blueprint for their next generation of artificial systems. Not too surprisingly, the structure of green leaves provides them an extremely high light-harvesting efficiency. Within their architecture are structures responsible focusing and guiding of solar energy into the light-harvesting sections of the leaf, and other functions.

The scientists decided to mimic that natural design in the development of a blueprint for artificial leaf-like structures. It led them to report their recipe for the “Artificial Inorganic Leaf” (AIL), based on the natural leaf and titanium dioxide (TiO2) — a chemical already recognized as a photocatalyst for hydrogen production.

The scientists first infiltrated the leaves of Anemone vitifolia — a plant native to China — with titanium dioxide in a two-step process. Using advanced spectroscopic techniques, the scientists were then able to confirm that the structural features in the leaf favorable for light harvesting were replicated in the new TiO2 structure. Excitingly, the AIL are eight times more active for hydrogen production than TiO2 that has not been “biotemplated” in that fashion. AILs also are more than three times as active as commercial photo-catalysts. Next, the scientists embedded nanoparticles of platinum into the leaf surface. Platinum, along with the nitrogen found naturally in the leaf, helps increase the activity of the artificial leaves by an additional factor of ten.

In his ACS presentation, Fan reported on various aspects of Artificial Inorganic Leaf production, their spectroscopic work to better understand the macro- and microstructure of the photocatalysts, and their comparison to previously reported systems. The activity of these new “leaves,” are significantly higher than those prepared with classic routes. Fan attributes these results to the hierarchical structures derived from natural leaves:

“Our results may represent an important first step towards the design of novel artificial solar energy transduction systems based on natural paradigms, particularly based on exploring and mimicking the structural design. Nature still has much to teach us, and human ingenuity can modify the principles of natural systems for enhanced utility.”

Sourced and published by Henry Sapiecha 9th April 2010

Danish Researchers Reveal New

Hydrogen Storage Technology

ScienceDaily (Sep. 8, 2005) — Scientists at the Technical University of Denmark have invented a technology which may be an important step towards the hydrogen economy: a hydrogen tablet that effectively stores hydrogen in an inexpensive and safe material.


With the new hydrogen tablet, it becomes much simpler to use the environmentally-friendly energy of hydrogen. Hydrogen is a non-polluting fuel, but since it is a light gas it occupies too much volume, and it is flammable. Consequently, effective and safe storage of hydrogen has challenged researchers world-wide for almost three decades. At the Technical University of Denmark, DTU, an interdisciplinary team has developed a hydrogen tablet which enables storage and transport of hydrogen in solid form.

“Should you drive a car 600 km using gaseous hydrogen at normal pressure, it would require a fuel tank with a size of nine cars. With our technology, the same amount of hydrogen can be stored in a normal gasoline tank”, says Professor Claus Hviid Christensen, Department of Chemistry at DTU.

The hydrogen tablet is safe and inexpensive. In this respect it is different from most other hydrogen storage technologies. You can literally carry the material in your pocket without any kind of safety precaution. The reason is that the tablet consists solely of ammonia absorbed efficiently in sea-salt. Ammonia is produced by a combination of hydrogen with nitrogen from the surrounding air, and the DTU-tablet therefore contains large amounts of hydrogen. Within the tablet, hydrogen is stored as long as desired, and when hydrogen is needed, ammonia is released through a catalyst that decomposes it back to free hydrogen. When the tablet is empty, you merely give it a “shot” of ammonia and it is ready for use again.

“The technology is a step towards making the society independent of fossil fuels” says Professor Jens Nørskov, director of the Nanotechnology Center at DTU. He, Claus Hviid Christensen, Tue Johannessen, Ulrich Quaade and Rasmus Zink Sørensen are the five researchers behind the invention. The advantages of using hydrogen are numerous. It is CO2-free, and it can be produced by renewable energy sources, e.g. wind power.

“We have a new solution to one of the major obstacles to the use of hydrogen as a fuel. And we need new energy technologies – oil and gas will not last, and without energy, there is no modern society”, says Jens Nørskov.

Together with DTU and SeeD Capital Denmark, the researchers have founded the company Amminex A/S, which will focus on the further development and commercialization of the technology.

Sourced and published by Henry Sapiecha 9th April 2010