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Will man mimick nature to power the hydrogen economy?

Artificial photosynthesis and solar cells are just one of the exciting projects that Mallouk's teams are working on.  (Source: Penn State University)
A new research study has created a synthetic photosynthetic complex which has a net efficiency of 0.3 percent

Photosynthesis is the fundamental energy capture process which forms the foundation of all life on Earth.  On a most basic level, it involves using sunlight to split water molecules into hydrogen and oxygen and then using the hydrogen captured to fuel sugar production.   With hydrogen becoming more popular as a possible alternative fuel source, many researchers have yearned to duplicate this most basic of natural processes to allow for cheap, efficient hydrogen production.  They had little success -- until now.

In the past, natural and synthetic dye molecules which tried to split hydrogen and water were consumed during the reactions and did not provide a sustained reaction.  Worse yet, the chemical reactions were often from a net perspective endothermic; in other words they required energy instead of producing it.  Part of this is because of the ease with which oxygen and hydrogen recombine, and the fact that most of these investigated catalysts also catalyze the recombination, destroying your products.

Thomas Mallouk, a DuPont Professor of Materials Chemistry and Physics, and W. Justin Youngblood, postdoctoral fellow in chemistry, together with collaborators at Arizona State University succeeded where others have failed. The researchers developed a dye/catalyst system that mimics the oxidative and electron transfer processes of photosynthesis, ultimately producing hydrogen gas.  Their findings were presented at the meeting of the American Association for the Advancement of Science today in Boston.

Clusters of molecules using iridium oxide molecules as a center catalyst, surrounded by light absorbing orange-red dye molecules comprise the finished product.  The 2 nm complexes are roughly half dye and half catalyst in terms of diameter.  Orange-red dye was selected due to its extensive experimental record and its ability to absorb high energy blue wavelength light.

Water molecules bond to the complex, and when the complex absorbs sunlight, it splits them into hydrogen and oxygen.  Mallouk enthuses upon its near biological efficiency, stating, "Each surface iridium atom can cycle through the water oxidation reaction about 50 times per second.  That is about three orders of magnitude faster than the next best synthetic catalysts, and comparable to the turnover rate of Photosystem II in green plant photosynthesis."

The process needs a tiny bit of juice to get started.  The voltage required to split water is 1.23 V, and the system is almost at this power level.  By adding 0.3 V from titanium dioxide anode and platinum cathode electrodes, the water begins to split.  Separating the electrodes effectively reduces hydrogen/oxygen recombination.

The current process has a positive efficiency of about 0.3 percent.  This sounds pretty measly, but as Mallouk puts it, "Nature is only 1 to 3 percent efficient with photosynthesis.  Which is why you cannot expect the clippings from your lawn to power your house and your car. We would like not to have to use all the land area that is used for agriculture to get the energy we need from solar cells."

Mallouk hopes to eventually achieve efficiencies better than that of natural processes.  By changing the molecular geometry, he plans on upping the efficiency by better allowing light to be absorbed or by improving the bonding of water molecules to the surface of the complex.

Mallouk states optimistically, "This is a proof-of-concept system that is very inefficient. But ultimately, catalytic systems with 10 to 15 percent solar conversion efficiency might be achievable.  If this could be realized, water photolysis would provide a clean source of hydrogen fuel from water and sunlight."

The fact that the efficiency is anywhere near that of the Photosystem II protein complex, a marvel of biological design, is impressive in itself.  The fact that this system could be competitive one day with modern solar technology (currently around 10 percent efficient) and help to replace fossil fuels is even more impressive. 

With hydrogen fuel looking more and more promising, Mallouk and Youngblood's research is certainly a significant breakthrough. 



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Big !
By perzy on 2/19/2008 5:43:37 AM , Rating: 1
This a lot bigger achivement than many realize! Mimicing fotosynthesis is a big step in human evoulution!
This will have a big impact on us in the long run, remember that.




RE: Big !
By rogard on 2/19/2008 6:45:04 AM , Rating: 2
If "mimicking photosynthesis" really was a step in human evolution, I'd be truly impressed. So our great grand grand children might be able to synthesize hydrogen with their photoactive...what? Hair? Skin? Welcome to the future. Welcome to a whole new twist in human evolution: The homo photosynthesis.


RE: Big !
By AnnihilatorX on 2/19/2008 7:30:51 AM , Rating: 3
Which adds a whole different meaning to sunbathing


RE: Big !
By Artistotle on 2/19/2008 2:48:15 PM , Rating: 2
Well, a lot of future theorists are proposing that technology is in fact the next frontier of our evolution. Modern societies have virtually no pressure to adapt to anything physically, but the convergence of man and machine is where we are heading. I think this has all sorts of interesting ramifications, very exciting stuff :)


RE: Big !
By rogard on 2/20/2008 6:04:34 AM , Rating: 2
I agree that the future evolution of mankind is an interesting topic. I just couldn't resist to poke fun at the literal meaning of the previous comment. The idea of a human being capable of photosynthesis is simply hilarious. Should've used the <irony> tag though... :-)


RE: Big !
By wordsworm on 2/19/2008 7:49:51 AM , Rating: 4
Does this mean we'll catch up to the evolution of trees? Yessss!!!!


RE: Big !
By drank12quartsstrohsbeer on 2/19/08, Rating: -1
RE: Big !
By SilentSin on 2/19/2008 11:42:21 AM , Rating: 4
Are you being serious or facetious? Oxygen naturally combines to form O2, not O3. To create O3 you need chemical or electrical catalysts or intense ultraviolet radiation (which is how the ozone layer is formed-very far above ground mind you). Beside that fact, the oxygen that is created is probably negligible in the grand scheme of things unless we were to blanket the entire planet with these contraptions.


RE: Big !
By geddarkstorm on 2/19/2008 12:18:59 PM , Rating: 2
But then, once we use the hydrogen fuel in say a fuel cell, it'll recombine with oxygen to form water. It's a cycle. A nice, juicy, happy cycle powered by the sun.


RE: Big !
By drank12quartsstrohsbeer on 2/19/08, Rating: -1
RE: Big !
By SilentSin on 2/19/2008 2:08:24 PM , Rating: 2
Actually I used to live in Raleigh where this was an increasing problem during summer. So while that is a problem, it is a problem stemming from other gases than pure oxygen (which is what is being produced here). Ground level ozone that is man-made is a result of not oxygen, but rather Nitrogen Oxides which are a main ingredient in car exhaust. When the NOx gases mix with other elements in the atmosphere and are exposed to high amounts of heat, ground based O3 occurs. However, even ground-based O3 does not have a long life as many materials found in buildings (such as paints, carpets, etc) will help to quicken breakdown of O3 back into O2 or other oxygen carrying molecules. Oxygen is a pretty reactive element which is why it is found in so many different compounds, O3 is a particularly unstable molecule and so would not last in that state for too long. It's only when there's an enormous amount of it being created all at once that the atmosphere can't handle it naturally and it becomes a problem for humans.

I just googled ozone and came up with this, give it a read if you wish: http://www.smartcommute.org/OzInfo.htm


I think that summary is unfair and deceiving
By winterspan on 2/19/2008 6:25:50 AM , Rating: 2
quote:
A new research study has created a synthetic photosynthetic complex which has a net efficiency of 0.3 percent


Why the hell did the writer have to throw in that seemingly very low percentage number write into the bold summary?
It doesn't even fit the context, assuming no one has done this before. It appears as if he is intentionally attempting to cast this work off as frivolous to the reader who skips over the article. I understand the 0.3 efficiency number is accurate, but I find it misleading to throw it right into the bold summary at the top without any background on the fact that photosynthesis in nature is nearly as inefficient.
Poor journalism.




By Darkskypoet on 2/19/2008 7:24:00 AM , Rating: 4
Actually it's not poor journalism. Poor journalism would be adding a derogatory adjective to the initial summary when describing the net efficiency. Any decently studied biology student / professional would probably understand photosynthesis isn't too much more efficient, and so the number would make sense to them, and definitively not seem to be bashing this new technology.

Considering that on Daily Tech, the majority of the tech articles expect, (nay demand), a certain baseline of knowledge to be understood properly in context; I believe your comment stems from the fact that that you lack such baseline knowledge to have gotten full value out of the little bold summary up top of this article.

I am not slagging you, and I understand that one could argue that this article is not the standard tech piece we usually read here, and as such shouldn't assume we know that 0.3% is pretty damn good. However, you must admit, that if you possessed the knowledge that Nature Brand photosynthesis was only 2-3% efficient, that you would indeed have gleaned the useful information right away, and we would not be having this discussion.

I'll reserve my calls of 'Bad Journalism' for when the summary up top reads something more like, "Idiot Professor's crazed synthetic Photo Synth barely better then doing nothing at all! Grade school teacher confirms he's 'never done much real work, always daydreaming with those small shifty eyes of his'."


By AnnihilatorX on 2/19/2008 7:33:28 AM , Rating: 2
It's not deceptive at all. The summary is merely stating a fact. While the summary did not compare to the natural efficiency but again the comparison isn't really the main focus of the report.

I think it's reader's responsibility to dig in further to something they see as unbelievable.


By tmouse on 2/19/2008 9:16:03 AM , Rating: 2
It would be equally bad to overemphasize the accomplishment and make it seem products are right around the corner. They do point out the natural efficiency later in the article. I find absolutely nothing misleading


Quick! Patent it!
By osalcido on 2/19/2008 3:13:56 AM , Rating: 2
God forbid humanity has a chance to utilize fundamental laws of physics to its advantage without paying a hefty ransom




RE: Quick! Patent it!
By Davelo on 2/19/2008 12:12:24 PM , Rating: 2
You haven't seen the bill yet. Of course there will be a price tag. There always is. The freebees never see the light of day.


RE: Quick! Patent it!
By clovell on 2/19/2008 2:04:03 PM , Rating: 2
You're misunderstanding the patent system. Without it, there is no incentive for businesses to develop or divulge trade secrets. The patent system grants a short period of exclusivity to business for an idea in exchange for free public use / ownership of that idea later on.

It actually encourages development, and is the reason we have generic drugs, among many other positive things. As with all things, it can be abused, but don't throw the baby out with the bathwater.


RE: Quick! Patent it!
By Darkskypoet on 2/19/2008 10:47:50 PM , Rating: 2
Actually... It is not why we have generic drugs... We have generic drugs only because for those drugs the patents have expired. Other nations oft times have generic drugs because they don't obey developed world's patent law.

I understand the incentive of patents in so far as they grant a monopoly for a short time for the company in question to recoup R&D. However, Drugs, computer software, etc; are oft times bad examples of abuse for said 'patent benefits'. There are many patents that should be tossed (software / silly general ones), and many times I can't humanely fault the pre-patent expiration production of HIV/AIDS meds, et cetera in poorer nations.

But; to say that without a patent system in place that companies would fail to innovate isn't true either. For the first that did in a non patent world would dominate competition, forcing them into innovation. In fact, it would remove the ability to milk certain patents, resting on their laurels until its time to make the next cash cow.

The patent system / Intellectual property laws, favor the stronger more established companies / developed world; as they then hold more monopolies for extended periods of time. As well, it could be said that it thwarts a more wide spread innovation, allowing any firm to leapfrog off the knowledge gained (and used) by any other firm. In this scenario, the ability to utilize other once patentable tech to improve it now, not in x years, would allow a much quicker incremental advance in tech. As well, it would engage many developing countries (China / India / et cetera) in improving, rather then counterfeiting.

A better strategy, would be to reduce patent protection times, perhaps striking a balance between the protectionism inherent in the current system, and the outright corporate / industrial warfare in the the no patent scenario.

Drugs, for instance, are a good case for shortened patent times, as mot developed countries are aging rapidly and the reduced drug costs / greater availability of generic drugs would save quite a few health plans / consumers a ton of money.

Added to shortened patent (monopoly condition) could be a simple royalty system adding a cent or two per pill or some such payable to the developer. However, said developer could not refuse to 'license' said tech to any firm producing. In this way, R&D can be recouped, and greater volumes of product can get to those in need.

Wow, as I've typed so much here; long story short, IP /patent changes could be beneficial to all.


Reminds me of...
By Trisagion on 2/19/2008 12:18:30 AM , Rating: 1
Chain Reaction, anybody?




RE: Reminds me of...
By Brandon Hill (blog) on 2/19/2008 12:28:16 AM , Rating: 2
Horrible, horrible movie. Not even the mighty Morgan Freeman could save it.


RE: Reminds me of...
By JonnyDough on 2/19/2008 12:30:50 AM , Rating: 1
I'd just like to say that I believe there are forces on earth we're unaware of that can provide more power than solar energy. Still, solar energy seems to me to be the most viable, free source we have. It's everlasting (at least until the sun burns out, and then...well there are other suns). Once we understand more about dark matter and so on, I believe we'll find our renewable resource. The idea of a crystal that can output a significant amount of energy over a long time is not that far fetched. We have no idea really what lies beyond our own galax, and for that matter, within it. This kind of news is exciting to me everytime I hear about advances in solar power, especially those that could possibly be commercialized. My hat is off to anyone who can get rid of our coal dependency. It is a horrible way to power our world.


RE: Reminds me of...
By Schrag4 on 2/19/2008 11:17:06 AM , Rating: 2
"(at least until the sun burns out, and then...well there are other suns)"

Yeah, then we just go to the next solar system, beam down to the first planet we find, and breathe the oxygen-rich, toxin-less air, walk upright in the earth-like gravity, and talk to the english-speaking alien race that lives there. I saw it on Star Trek, it must not be that hard!

In all seriousness, I suppose by the time our sun goes out, we may have advanced our technology (and our genetics??) enough to adapt to other solar systems and their planets, or maybe adapt them to us (terraforming). Of course none of us or our great-great granchildren will see any of this. If you think we'll have these types of technologies sooner, then you're like the crowd from 50 years ago who thought we'd have flying cars by the year 2000.

Cool article though. I, too, get a little excited inside when I hear about these new energy advancements.


RE: Reminds me of...
By JonnyDough on 2/19/2008 2:26:17 PM , Rating: 1
"I saw it on Star Trek, it must not be that hard!"

Heh, my post was a bit of sarcasm. By the time the sun burns out the human race will likely be extinct due to something else. Collision with an asteroid, global temperature change, a disease. We're not likely to ever hear on the news that our sun just ran out of hydrogen. =)


What's the big deal?
By 67STANG on 2/19/2008 1:07:42 AM , Rating: 2
People have been using solar energy to produce Hydrogen for a while now... Of course the configuration (Solar panels powering electrolyzers) is different than this, but how is this new discovery a better solution? Seems like it will take ages to get to the efficiency that we are already at..




RE: What's the big deal?
By eye smite on 2/19/2008 6:38:06 AM , Rating: 4
Meh, it's just another advance in technology, not any kind of replacement for existing methods. It shows they're researching in ways they haven't thought of before, and who knows what collateral tech might come as a result. It makes for interesting reading if nothing else.


A net efficiency of 0.3 percent?
By Polynikes on 2/19/2008 1:28:57 AM , Rating: 2
Gotta start somewhere, I suppose. :)




By Omega215D on 2/19/2008 2:03:11 PM , Rating: 2
I bring you the first Silicon based tree! =D


Compression
By Are Back on 2/19/2008 1:53:18 PM , Rating: 2
I'm curious...

Isn't the compression and storage of hydrogen gas a hurdle as large as the production of it?

So, if you are oozing tiny amounts of hydrogen from these cells, where will the energy to compress it come from....the nearby coal fired plant?




RE: Compression
By MadMaster on 2/19/2008 2:41:08 PM , Rating: 2
Yep, that's one of the many issues with hydrogen.

Look at this...

http://photovoltaics.sandia.gov/weather/Weather.ht...

An optimistic average insolation is about 10 kWh/m2/day. (maybe in mountains, very dry places, etc.)

At .003 efficiency, that's 36 watthours per day (of hydrogen energy produced). A vehicle requires about (give or take) 200 watthours to go a mile. Hydrogen fuel cells will require at least twice that due to inefficiencies in the fuel cell.

Generating electricity from photovoltaic cells is about 20% (40% for very efficient ones). This guy is hoping to get 15% efficiency into hydrogen? Even with that (optomistic) efficiency, he won't be able to sell this...

It would be a heck of a lot easier (and efficient) to just charge a plug in hybrid with generated electricity than convert that electricity to hydrogen and then back to electricity through a fuel cell.


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