Alloy Could Produce Hydrogen Fuel Using Sunlight 360
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."
Re:awful amount of could in the article.. (Score:5, Informative)
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.