 surrounded by organic molecules.)
RUTHENIUM CRYSTALS: Two separate groups of researchers working on two separate parts of the photosynthetic reaction happened to be using the same class of catalyst--ones with an atom of the metal ruthenium (seen here) surrounded by organic molecules.
Image: Courtesy of Periodictableru, via Wikimedia Commons
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Sunlight can provide more than enough energy to meet our needs—in theory. In practice, the skies are sometimes covered with clouds—and whether fair or overcast, the sun daily disappears behind the horizon. To get around these limitations, scientists have worked for years on new ways of converting sunlight into chemical energy, artificial forms of photosynthesis that would store solar energy in liquid or gaseous form—a "solar fuel." For years, they have sought a chemical catalyst that can perform this complex feat of chemical processing. Now some researchers think they may have found it.
Thomas Meyer came upon the solution almost by accident. Meyer, a chemist at University of North Carolina at Chapel Hill and director of its Energy Frontier Research Center in Solar Fuels, noticed that two separate groups of researchers working on two separate parts of the photosynthetic reaction happened to be using the same class of catalyst—ones with an atom of the metal ruthenium surrounded by organic molecules. One group used this type of catalyst to split water into hydrogen and oxygen; the other one was splitting carbon dioxide into carbon monoxide and oxygen. "Finding a single catalyst that does both was a big surprise," Meyer says.
By combining the two steps and using the same catalyst, Meyer realized that they could reproduce photosynthesis in its entirety. Whereas natural photosynthesis, after multiple reactions, converts water, carbon dioxide and sunlight into oxygen and energy-rich fuels such as sugar, Meyer's version converts water and carbon dioxide into oxygen, hydrogen and carbon monoxide—and the latter can be combined with hydrogen to eventually make a fuel such as methanol.
These findings suggest that it may be feasible to take carbon emitted from, say, a coal plant and use it to make a liquid fuel such as methanol that replaces or supplements fossil fuels for transportation or electricity generation. How would it work? Carbon dioxide-laden water from a fossil-fuel plant would pass across ruthenium catalyst membranes, which would trigger artificial photosynthesis, breaking it down into oxygen as well as constituents that can be converted to fuel. Electrical energy to drive the catalytic reaction would come from solar-power cells—although eventually researchers might be able to modify the catalyst to absorb sunlight directly. "That really would make it like photosynthesis," Meyer says. He and his colleagues detailed their findings online June 4 in Proceedings of the National Academy of Sciences.
The work is "a very interesting result from the point of view of fundamental science," says Princeton University chemist Andrew Bocarsly, who did not take part in this research. "It could be a dramatic simplification of a natural system, which could be very useful from a pragmatic point of view." (Bocarsly is working on ways of splitting carbon dioxide to create carbon monoxide, which can then be used to manufacture methanol and other fuels. Massachusetts Institute of Technology chemist Dan Nocera is developing cobalt-based catalysts that split water.)
Meyer's finding, however, needs further development before it is ready for commercial-scale use. For instance, Meyer's ruthenium catalyst is not very energy efficient when it comes to splitting carbon dioxide. It requires 1.65 volts to drive the reaction. By contrast, Bocarsly's system can turn carbon dioxide into methanol, "an arguably much more useful molecule, with 0.2 volts." Meyer acknowledges this drawback, and he's working on improving the process so that it works faster and needs less voltage. "We're continuing the process of iteration to make things better," he says.
Nevertheless, Meyer's experiment with the ruthenium catalyst, the first to do photosynthesis in its entirety, is a potentially big practical breakthrough.
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12 Comments
Add CommentThat sounds like very promising research, but I don't think that the oil companies will like too much.
Reply | Report Abuse | Link to thisLooks great - smells bad!
Reply | Report Abuse | Link to thisAs stated by http://en.wikipedia.org/wiki/Ruthenium#Mining
"Roughly 12 tonnes of Ru is mined each year with world reserves estimated as 5,000 tonnes. The composition of the mined platinum group metal (PGM) mixtures varies in a wide range depending on the geochemical formation. For example, the PGMs mined in South Africa contain on average 11% ruthenium while the PGMs mined in the former USSR contain only 2% based on research dating from 1992."
Ruthenium, like the other platinum group metals, is obtained commercially as a by-product from nickel and copper mining and processing as well as by the processing of platinum group metal ores. During electrorefining of copper and nickel, noble metals such as silver, gold and the platinum group metals settle to the bottom of the cell as anode mud, which forms the starting point for their extraction..."
SO EXCITED! My writer's bio reads: "I aim to retool humans from food dependency to photosynthesis, end world hunger, shift global wealth to sun producing poor nations, and front my own metal band" But replacing fossil fuel dependence with a catalyst (from an element, #44, that fosters my name) using photosynthesis, is a mind blowing treat of scientific discovery. (always felt there was a link) Thank you, Mr. Thomas Meyer, and your team at Chapel Hill!
Reply | Report Abuse | Link to thisFrom the same source:
Reply | Report Abuse | Link to thisFission products of uranium-235 contain significant amounts of ruthenium and the lighter platinum group metals and therefore used nuclear fuel might be a possible source of ruthenium. The complicated extraction is expensive and the radioactive isotopes of ruthenium that are present would make storage for several half-lives of the decaying isotopes necessary. This makes this source of ruthenium unattractive and no large-scale extraction has been started.
With the longest isotope half life being just over a year. And with the other potential uses described in the same source further down the page, this could also be a catalyst to start up the waste refining processes.
Obviously it would be far cheaper to use nuke power the supply the energy then electricity from solar cells.
Reply | Report Abuse | Link to this"Meyer's finding, however, needs further development"
Reply | Report Abuse | Link to thisI'll say ........
As others have pointed out ruthenium is very rare, a point that should have been mentioned in the article but wasn't. The suggestion this might be a reall solution to our energy/environmental crisis is absurd.
Reply | Report Abuse | Link to thisA case of biomimicking. Photosynthesis is indeed a wonder that keeps the plants alive and many applications can be there for energy production especially in solar power.
Reply | Report Abuse | Link to thisDr.A.Jagadeesh Nellore(AP),India
E-mail: anumakonda.jagadeesh@gmail.com
That seems like a plausible and promising research. If scientist could make it work, it would change our society for the better
Reply | Report Abuse | Link to thiswhat the fuss is about :
Reply | Report Abuse | Link to thisConvert H2O via electrolysis to it's parts or A commercial,(@13.5 keV),compressing station to seperate and store liquid Oxygen, Hydrogen, Nitrogen, or other rare gasses. Any combination thereof as well as Catalytic reactions whatcha got?.
So what's the area required to make it happen with solar power? The average amount of energy required to peak power a home is?
Hook up that old gas powered engine add a generator whatcha got? Oh something about Hydrogen killing the metal surfaces of a combustion engine ...fix it...To further that compressing stations can be tailor made.If such systems were to produce a percentage more Compressed Liquid Gas than used, store it all and sell for a profit for the owner/ opperator...end of problem. And we can all play with liquid nitrogen etc. I can imagine making superconductors in my garage then! Tons of fun in retirement!
Add to all this regulations or cockblocked technology via Lobbyists which prevent a mass of people from achieving independance from Oil, Nuclear, you get what we have today. Materials are not that expensive! It's the Lobbyists for the current power suppliers... they make it so. Technology has outstripped what we use as energy today ..time to get real!
I do like this article but the ballance of the equasions mean a central source of energy and a limited resource base materials >.< ...we are not....
How's your solution to the problem coming then?
Reply | Report Abuse | Link to thisIndustrial hemp has great potential to be used as a fuel.
Reply | Report Abuse | Link to this40pct of the seed is oil. Of course little research is being done to improve hemp yield because even though it contains little THC, it is still illegal. Thousands of products can be made with Hemp, including a car with low weight car panels 10 x stronger than steel. Ford made a car made out of hemp in 1941. You can google this. The exhaust is biodegradeable, and the car is carbon neutral as hemp crops suck up carbon.