Splitting water to create renewable energy simpler than first thought?

May 16, 2011

(PhysOrg.com) -- An international team, of scientists, led by a team at Monash University has found the key to the hydrogen economy could come from a very simple mineral, commonly seen as a black stain on rocks.

Their findings, developed with the assistance of researchers at UC Davis in the USA and using the facilities at the Australian Synchrotron, was published in the journal Nature yesterday 15 May 2011.

Professor Leone Spiccia from the School of Chemistry at Monash University said the ultimate goal of researchers in this area is to create a cheap, efficient way to split , powered by sunlight, which would open up production of hydrogen as a clean fuel, and leading to long-term solutions for our renewable .

To achieve this, they have been studying complex catalysts designed to mimic the catalysts plants use to split water with sunlight. But the new study shows that there might be much simpler alternatives to hand.

“The hardest part about turning water into fuel is splitting water into hydrogen and oxygen, but the team at Monash seems to have uncovered the process, developing a water-splitting cell based on a manganese-based ," Professor Spiccia said.

"Birnessite, it turns out, is what does the work. Like other elements in the middle of the Periodic Table, manganese can exist in a number of what chemists call oxidation states. These correspond to the number of oxygen atoms with which a metal atom could be combined," Professor Spiccia said.

"When an electrical voltage is applied to the cell, it splits water into hydrogen and oxygen and when the researchers carefully examined the catalyst as it was working, using advanced spectroscopic methods they found that it had decomposed into a much simpler material called birnessite, well-known to geologists as a black stain on many rocks."

The manganese in the catalyst cycles between two oxidation states. First, the voltage is applied to oxidize from the manganese-II state to manganese-IV state in birnessite. Then in , birnessite goes back to the manganese-II State.

This cycling process is responsible for the oxidation of water to produce oxygen gas, protons and electrons.

Co-author on the research paper was Dr Rosalie Hocking, Research Fellow in the Australian Centre for Electromaterials Science who explained that what was interesting was the operation of the catalyst, which follows closely natures biogeochemical cycling of manganese in the oceans.

"This may provide important insights into the evolution of Nature’s water splitting catalyst found in all plants which uses manganese centres,” Dr Hocking said.

“Scientists have put huge efforts into making very complicated manganese molecules to copy plants, but it turns out that they convert to a very common material found in the Earth, a material sufficiently robust to survive tough use.”

The reaction has two steps. First, two molecules of water are oxidized to form one molecule of oxygen gas (O2), four positively-charged hydrogen nuclei (protons) and four electrons. Second, the protons and electrons combine to form two molecules of hydrogen gas (H2).

The experimental work was conducted using state-of-the art equipment at three major facilities including the Australian Synchrotron, the Australian National Beam-line Facility in Japan and the Monash Centre for Electron Microscopy, and involved collaboration with Professor Bill Casey, a geochemist at UC Davis.

"The research highlights the insight obtainable from the synchrotron based spectroscopic techniques – without them the important discovery linking common earth materials to water oxidation catalysts would not have been made," Dr Hocking said.

It is hoped the research will ultimately lead to the development of cheaper devices, which produce .

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User comments : 13

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rich_leatzau
1 / 5 (2) May 16, 2011
stan meyer.
already did this
epsi00
1 / 5 (2) May 16, 2011
Does that mean that these chemists will suffer the same fate as Stan's and drop dead suddenly in the middle of a lecture?
WhiteJim
1 / 5 (2) May 16, 2011
Sounds like something simple enough to have been figured out hundreds of times already by many different chemists over the years. Anyone got a Pelican Brief on coincidental deaths of chemists in related fields of research?
holoman
5 / 5 (3) May 16, 2011
Marketing data.

No input energy vs. output energy data. Efficiency ?
gmurphy
4.7 / 5 (3) May 16, 2011
@rich_leatzau, Stan Meyer did not do this already. His wikipedia article is quite informative.

@epsi00, He died at a restaurant, also on his wiki page
Cynical1
2 / 5 (4) May 16, 2011
this info was already well known and suppressed by government shills of the oil industry.
SteveL
4 / 5 (1) May 16, 2011
stan meyer.
already did this


Possibly... Although I don't see how this could work as described. Not enough info.

http://www.rexres...erhy.htm

Looks like Mr. Meyer may have been his own worst enemy. Read the section at the bottom.
Sean_W
3.7 / 5 (3) May 16, 2011
The author didn't need to limit the applications of this to renewable energy which immediately suggests hydrogen as a transportation fuel. The ability to make hydrogen less expensively than from fossil fuels and far away from refineries would be very important for many applications.
krundoloss
3 / 5 (2) May 16, 2011
Quickly, Deploy the Oil Company Snipers!
TabulaMentis
1 / 5 (4) May 16, 2011
Beware, the Russians are watching! People who want cheap H2O power on demand will want to learn more about dark energy/matter..........
sunapi386
3 / 5 (2) May 16, 2011
This is not at all useful, since it's not really a catalyst. They need electrolysis to get to the first step.. and the second step is not reversible naturally.
wwqq
5 / 5 (3) May 16, 2011
stan meyer.
already did this


Bullshit. Stan Meyer was a hopeless crank who claimed to have discovered free energy(in the sense of perpetual motion machines of the second kind); his investors took him to court and he was found guilty of "gross and egregious fraud". What he had was nothing more than a very inefficient electrolytic cell with no redeeming features or remarkable characteristics.
that_guy
not rated yet May 24, 2011
This is not at all useful, since it's not really a catalyst. They need electrolysis to get to the first step.. and the second step is not reversible naturally.

The definition of catalyst is a substance that helps a chemical reaction without undergoing any permanent change.

Since, after all the steps, it reverts to its original form, technically that adheres to the definition of being a catalyst.

I agree with holoman, this article would be enormously more informative if it gave us some numbers.