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Alloy Could Produce Hydrogen Fuel Using Sunlight
intellitech writes "Using state-of-the-art theoretical computations, a University of Kentucky-University of Louisville team demonstrated that an alloy formed by a 2 percent substitution of antimony (Sb) in gallium nitride (GaN) has the right electrical properties to enable solar light energy to split water molecules into hydrogen and oxygen, a process known as photoelectrochemical (PEC) water splitting. When the alloy is immersed in water and exposed to sunlight, the chemical bond between the hydrogen and oxygen molecules in water is broken (abstract). Because pure hydrogen gas is not found in free abundance on Earth, it must be manufactured by unlocking it from other compounds. Thus, hydrogen is not considered an energy source, but rather an 'energy carrier.' Currently, it takes a large amount of electricity to generate hydrogen by water splitting. As a consequence, most of the hydrogen manufactured today is derived from non-renewable sources such as coal and natural gas. The team says the GaN-Sb alloy has the potential to convert solar energy into an economical, carbon-free source for hydrogen."
Is this a superior alternative to the work that Dan Nocera's been doing at MIT with catalysts to make electrolysis take less energy?
-jcr
The only title of honor that a tyrant can grant is "Enemy of the State."
Is there a cheap way to contain hydrogen yet?
Do you care about your fellow man who was born with less privilege than you? Then work hard to make stories like this into a reality so that every poor family can have the access to cheap energy to heat their homes and to power the car in their driveway.
That's a better story than lowering the standard of living for everyone. I'd rather use technology to raise everyone up, even if it is only to the modest levels that you and I take for granted.
"But will never be made commercially available because it would result in a breakdown of the energy cartel's strangle-hold on the world's economy."
I know we're supposed to love all technological solutions for our energy problems, but I'm just not convinced anymore.
When I look at how badly most things are managed, at the ignorance and greed that rule the world, I'm quite convinced that properly implementing what we already know could solve more problems than inventing further methods and discovering new things. In everything from energy policy to urban planning to human health we could achieve an almost paradisaical state if we just chose to do those things correctly that we already know how to do correctly and assisted the entire human race in doing the same.
I'm not advocating cultural imperialism here, I'm just there's plenty of universal ground on which to share with any persons or cultures easily implemented, universally agreeable methods.
We've used solar power to split water into hydrogen for decades, what matters is cost. How does this compare with standard solar splitting based on surface area? Do you need a crystalline structure to work? Given that raw silicon is more common and more used I expect it's much cheaper. The article talks about semiconductors so it probably needs a crystal structure (drives up cost), so even with better efficiency (single step vs multi step splitting) it's still probably more costly.
How many of these are going anywhere years later?
Most aren't. Some are. That's pretty much the way R&D works: most projects fail, but the ones that succeed change our lives, generally for the better. If you're not interested in hearing about the early stages, when success or failure is impossible to predict, that's fine; no one's making you read those stories.
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
Imagine you're stuck in the desert with a bottle of water... you have to take a pick whether you drink your water or pour it in your car
Easy answer really. Drink your water and pee on your car.
ChE here. I read the article (hooray for university journal access), and I know exactly why there's so much hedging: this is a purely computational, DFT paper, with no experimental results to back it up. In the academic world this is not particularly uncommon, and DFT studies are an amazingly powerful tool to identify (potentially) optimal material combinations that would take researchers centuries to discover by systematic experimentation. But that's just it: "potentially". DFT often (necessarily) overlooks potential external effects that only occur in real systems. Somebody higher up really jumped the gun by making a full press release on a typical journal article in the photocatalysis field.
Gallium nitride (GaN) is used to make blue LED chips, typically vacuum deposited on top of sapphire wafers. While it is a very good semiconductor, it is an order of magnitude more expensive than silicon wafers. Unless there is a huge breakthrough in mass manufacturing cheap GaN wafers, it will be much cheaper to use silicon solar cells to generate electricity and electrolyze water with it.
Does the paper talk about the efficiency of this solution vs Photovoltaic panels and electrolysis? If the hydrogen and oxygen would be split over a large area (say a roof or larger), how would the gasses be collected? It sounds like an interesting result, but not so practical in application...
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People deciding to be calm and logical and sacrificing for the good of humanity as a whole? (The opposite of the ignorance and greed and fear we see all around us.) Or some guy in a lab coat eventually inventing a quick technical fix?
Personally I think cold fusion (or a similarly improbable technological breakthrough like the sunlight->metal->hydrogen described in this article based solely on computer simulation) is by far the more likely of the two possibilities, so I find joy in reading stories like this one, and continue to hope that someday, one of them will come to fruition.
2 weeks ago this same source reported on research at the PNWNL that uses a Nickel catalyst for a 1000x improvement over the platinum catalyst process now used, for example, on the ISS.
It uses gallium, which also makes great solar cells, more efficient than anything else. But the cost of gallium solar cells is so high that they're only used on spacecraft. They're about 3x more efficient than silicon solar cells, and 300x more expensive.
Just make your hydrogen to use in the chemical plants this way instead of reforming natural gas. Ammonia, ammonium sulphide etc etc comes from hydrocarbons now and it's nice to have an alternative way of getting it for when oil and natural gas get to be rare and expensive things.
I don't see anyone else mentioning this... but isn't hydrogen explosive?
The goal of computer science is to build something that will last at least until we've finished building it.