A team of scientists from Kentucky has discovered a way of using a cheap semiconductor together with ordinary sunlight to separate water into oxygen and hydrogen. This could allow water to be realistically used as a source of carbon free fuel.
The scientists, says tgdaily, have demonstrated, through the use of theoretical computations, that when a prepared alloy is immersed in water and exposed to sunlight it breaks the chemical bonds between the oxygen and hydrogen so that the hydrogen can be collected.
The relatively cheap alloy, a 2% substitution of antimony in gallium nitride (GaN-Sb), is shown by the research to enable the process of photoelectrochemical (PEC) water splitting.
As this newly formed substance acts as a catalyst in this process it also means that it never wears out and is not consumed.
"Previous research on PEC has focused on complex materials. We decided to go against the conventional wisdom and start with some easy-to-produce materials, even if they lacked the right arrangement of electrons to meet PEC criteria," said Professor Madhu Menon of the University of Kentucky.
"Our goal was to see if a minimal 'tweaking' of the electronic arrangement in these materials would accomplish the desired results."
As hydrogen is not readily available it has to be extracted from other compounds, which takes huge amounts of traditional power so carbon is released at this stage making the process not particularly environmentally friendly. But using this alloy would mean that the released hydrogen could provide a carbon free source of fuel using the power of the sun.
But this of course is totally reliant on the transfer of the blackboard theory to the acid test of the practical solution.