MIT's 'Artificial Leaf' Makes Fuel From Sunlight

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MIT's 'Artificial Leaf' Makes Fuel From Sunlight

Posted by Soulskill on Friday September 30, 2011 @05:01AM from the do-you-think-energy-just-falls-off-trees dept.

New submitter nfn writes "MIT has published a new paper (abstract), along with a video of a working prototype, of what they're describing as an 'Artificial Leaf' that separates water into oxygen and hydrogen using cheap, non-exotic materials. 'The artificial leaf — a silicon solar cell with different catalytic materials bonded onto its two sides — needs no external wires or control circuits to operate. Simply placed in a container of water and exposed to sunlight, it quickly begins to generate streams of bubbles: oxygen bubbles from one side and hydrogen bubbles from the other. If placed in a container that has a barrier to separate the two sides, the two streams of bubbles can be collected and stored, and used later to deliver power: for example, by feeding them into a fuel cell that combines them once again into water while delivering an electric current.' No word on the arrival of 'Artificial Salads,' or when any of their other alchemy projects will bear artificial fruit."

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Any minute now... by ackthpt · 2011-09-30 05:09 · Score: 2

OPEC assassins will strike and this will be nothing more than a small pile of mysterious rubble and ash in Cambridge, Massachusetts.

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A feeling of having made the same mistake before: Deja Foobar
1. Re:Any minute now... by fnj · 2011-09-30 05:26 · Score: 2, Insightful
  
  Yes; the (R) and (D) for the most part is just a big conspiracy to block any meaningful change. Of course you only mentioned one "side" which is no better than the other. In truth both "sides" are evil.
  The real battle is between the establishment and the outsiders - people who actually have independent critical thought.
2. Re:Any minute now... by elrous0 · 2011-09-30 05:39 · Score: 2
  
  No, they'll just wait and see if it's even practical to manufacture large scale. If it is, they'll either swoop in and buy up all the companies/patents involved or have their government lapdogs in Congress bury it under volumes of obstructive laws and regulations (you see they DO believe in govt regulation, just as long as it effects competitors but not themselves).
  
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  SJW: Someone who has run out of real oppression, and has to fake it.
3. Re:Any minute now... by DanTheStone · 2011-09-30 05:42 · Score: 2
  
  Of course you only mentioned one "side" which is no better than the other.
  Someone does not understand the meaning of "vice versa" (even if he did spell it wrong).
4. Re:Any minute now... by ColdWetDog · 2011-09-30 05:43 · Score: 2
  
  No Worries for the Greens, The government will give a couple billion dollars to prop up yet another failing "solar" company that cannot make it without a handout.
  As opposed to the trillions of dollars in 'handouts' to Saudi Arabia and the rest of the Middle East to keep the oil flowing? Or did you think we like to support backwards misogynist despots because they're just like us? (A reasonable supposition, I suppose).
  
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  Faster! Faster! Faster would be better!
5. Re:Any minute now... by flaming+error · 2011-09-30 06:21 · Score: 2
  
  The government props up the oil industry, too. And judging from their profits, they most decidedly could make it without the handout.
  So it's not clear to me that money diverted to green energy is any worse spent than money diverted to black gold.
6. Re:Any minute now... by ewieling · 2011-09-30 06:56 · Score: 2
  
  It seems to me (R) generally want to deregulate business and regulate our personal lives. The (D) generally want to regulate business and deregulate our personal lives. This is the real difference.
  
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  I really shouldn't have used someone else's email address for this account.
7. Re:Any minute now... by lgw · 2011-09-30 08:50 · Score: 2
  
  The (D) want to regulate my video games, my shower, my toilet, my trash, my building materials, my car, my power sources, my energy consumption, my ...
  The (R) only seem to want to regulate my sex life.
  
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  Socialism: a lie told by totalitarians and believed by fools.
Losing Hydrogen by jameskojiro · 2011-09-30 05:14 · Score: 4, Funny

I think all this hydrogen tech is very dangerous, we will start burning hydrogen and more of it will leak and escape from the earth since it is so light and before too long we will run out of water. Oh we will have plenty of oxygen, but the oceans will dry up and all life will die except the giant sandworms... At least we will have spice.

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Tsukasa: All I really want, is to be left alone...
1. Re:Losing Hydrogen by Baloroth · 2011-09-30 05:59 · Score: 2
  
  Yeah, and it also makes a giant *WHOOOOSH* when it does so.
  
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  "None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
2. Re:Losing Hydrogen by wagnerrp · 2011-09-30 06:12 · Score: 3, Informative
  
  Hydrogen is reactive. It will react with something on the way up through the atmosphere, that makes it sufficiently heavy to stick around. The problem with helium is that it is inert. It's perfectly content on its own, so it will simply float to the top of the atmosphere and exist in trace densities not economical to capture.
3. Re:Losing Hydrogen by istartedi · 2011-09-30 07:24 · Score: 3, Funny
  
  OMG! You're right. It'll react and form hydrogon peroxide. This will mix with rain water and get in people's hair. We'll turn blonde, which means we'll start making stupid dec.... Oh no. It's too late, it's started already. RUN!!!
  
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  For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
Oh boy by JustAnotherIdiot · 2011-09-30 05:15 · Score: 2, Funny

The energy crisis is solved for the 6th or 7th time this year.

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What do I know, I'm just an idiot, right?
Clean water? by Anonymous Coward · 2011-09-30 05:25 · Score: 3, Interesting

So, dirty water and sunlight go in, hydrogen and oxygen go out.
Then the hydrogen and oxygen go into a fuel cell, and electricity and pure water come out.
Efficiency isn't anywhere near perfect, but the benefits to a cycle that turns sunlight and dirty water into electricity and pure water are pretty obvious.
1. Re:Clean water? by Crudely_Indecent · 2011-09-30 06:55 · Score: 2
  
  Oh yeah, because solar stills produce hydrogen and oxygen as well as water by utilizing electricity.
  The only thing they have in common is that they use the sun (although, in very different ways). The artificial leaf doesn't produce water, at all. Clean water is a byproduct of utilizing the hydrogen as a fuel (as is heat).
  Nothing like a solar still.
  Although we don't know a price on these devices, they are made from non-exotic (read common) materials. Even if they cost more than pocket change, the longer they are in operation the more power they produce, only requiring water. Eventually, the value of the power produced will exceed the cost of the device.
  
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  "Lame" - Galaxar
no, maybe an update... Re:Duplicate by Fubari · 2011-09-30 05:33 · Score: 2

You're talking about this slashdot entry from 5 months ago: http://hardware.slashdot.org/story/11/03/28/239212/artificial-leaf-could-provide-cheap-energy
Not exactly a dup; they link to different articles.
This one's article has a video showing the prototype in operation, which is kind of cool.
The old one's article has no video, but they basically make the same points in text.
Re:Now do it for CO2 by Attila+Dimedici · 2011-09-30 05:39 · Score: 3, Informative

Actually, you bring up a decent point. Hydrogen is not very energy dense. This system would be great if we had a practical fusion reactor, but we don't. A much superior system would be one which takes sunlight, CO2 and water and produces a complex hydrocarbon that could then be used as fuel.

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The truth is that all men having power ought to be mistrusted. James Madison
Re:Duplicate (from the 19th century) by GrumpySteen · 2011-09-30 05:51 · Score: 3, Funny

> Seems to me like saying a Reese's Peanut Butter Cup is a new discovery because they mixed chocolate with peanut butter.
That's fucking incredible!! When did they do that?!?! Why wasn't I told????
Re:Now do it for CO2 by h4rr4r · 2011-09-30 06:02 · Score: 2

Once you have hydrogen and a source of CO/CO2 like a coal power plant you can make whatever hydrocarbons you want.
Re:Duplicate (from the 19th century) by Anonymous Coward · 2011-09-30 06:03 · Score: 2, Interesting

This is, in fact, a revolutionary new catalyst potentially worth billions. It does the same thing as conventional electrolysis, but is more than 20 times as efficient as just sticking two wires into a bucket. When I saw Nocera present this research at the Spring ACS conference, my jaw was just about on the floor.
Re:Back in High School by Bengie · 2011-09-30 06:07 · Score: 2

The real question is if it is more efficient than just charging a better with a solar panel. Since that Hydrogen is just a storage medium for "energy".
Re:Back in High School by Dr_Barnowl · 2011-09-30 06:09 · Score: 4, Informative

The innovative bit is the cobalt catalyst. A lot of other designs use toxic electrolytes (as you mention) or expensive rare metal catalysts. This one has the advantage that all the raw materials are relatively cheap, for a solar panel design - no expensive platinum, gadolinium, etc.
Re:Is this novel? by nomel · 2011-09-30 06:57 · Score: 2

Having a non corroding electrode, not requiring lots of electrolytes, and doing it all with cheap materials, is what makes it very interesting.
This is an interesting electrolysis problem more than a "power something with a solar cell" problem.
Re:Oh Great, another way to go Boom by Sqr(twg) · 2011-09-30 07:49 · Score: 2

"Hydrogen-Oxygen explosions are no joke." - Yes they are!
Few fuels contain as little energy per unit volume as hydrogen at atmospheric pressure. Two gallons of H2 is less than the fuel in a cigarette lighter.
My high school chemistry teacher used to fill balloons with H2 and O2 at stoichiometric ratio and hold them over a bunsen burner (on a 1 meter stick). They make a large pop of course, but the effect is not much larger than when the balloon is filled with pure O2 and the only fuel is the balloon itself.
Hydrogen *is* dangerous in very large quantities, or when combined with other fuels, because it ignites in a very large range of fuel/air ratios, but bomb-making-material it is not.