According to the researchers, an alloy formed by a 2 percent substitution of antimony (Sb) in gallium nitride (GaN) can be partially submerged in water to break the chemical bond between the hydrogen and oxygen molecules in water, as long as the alloy is exposed to sunlight. In effect, the alloy serves as a novel photoelectrochemical (PEC) catalyst that would allow the simple production of hydrogen.
"Previous research on photoelectrochemical [water splitting] has focused on complex materials," Madhu Menon, aprofessor at the UK Center for Computational Sciences said. "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 [photoelectrochemical] water splitting criteria. Our goal was to see if a minimal 'tweaking' of the electronic arrangement in these materials would accomplish the desired results."
Gallium nitride is a semiconductor that has been in widespread use to make bright-light LEDs since the 1990s. Antimony is a metalloid element that has been in increased demand in recent years for applications in microelectronics. The GaN-Sb alloy is the first simple, easy-to-produce material to be considered a candidate for PEC water splitting, the researchers said. They stressed that the alloy functions as a catalyst in the PEC reaction and it is not consumed and may be reused indefinitely. there was no information how effective the use of the alloy is.
The researchers said they are testing the alloy to convert solar energy to hydrogen.