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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."
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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Wanted: monovalent to occupy vacant orbital. It's a quad, but the other three spots are spoken for. If you are an H, we'll be an alkane. If you're a hydroxyl, we'll be an alcohol.
Obi-Wan: "I felt a great disturbance in the Force, as if millions of voices suddenly cried out in terror and were sudden
Really? I work about 90 hours a week, and haven't had a single week actually "off" in about ten years.
Selfish bastard. You could share some of that work, there's enough to do for two or three people there.
Nothing quite beats the misery of walking out of a nice, 296 Kelvin mall into the blistering, 310 Kelvin heat in the summer time, only to sit down in your 344 Kelvin car, cursing and swearing at all that damned free energy the sun packed into your car.
Fixed that for you. It's 21st century already.