Via Kurzweilai.com: An inexpensive renewable source of clean-burning hydrogen fuel for transportation and industry
In an engineering first, Stanford University scientists have invented
a low-cost water splitter that uses a single catalyst to produce both
hydrogen and oxygen gas 24 hours a day, seven days a week.
The researchers believe that the device, described in an open-access study published today (June 23) in Nature Communications, could provide a renewable source of clean-burning hydrogen fuel for transportation and industry.
“We have developed a low-voltage, single-catalyst water splitter that
continuously generates hydrogen and oxygen for more than 200 hours, an
exciting world-record performance,” said study co-author Yi Cui, an associate professor of materials science and engineering at Stanford and of photon science at the SLAC National Accelerator Laboratory.
The search for clean hydrogen
Hydrogen has long been promoted as an emissions-free alternative to
gasoline. But most commercial-grade hydrogen is made from natural gas — a
fossil fuel that contributes to global warming. So scientists have been
trying to develop a cheap and efficient way to extract pure hydrogen
from water.
A conventional water-splitting device consists of two electrodes
submerged in a water-based electrolyte. A low-voltage current applied to
the electrodes drives a catalytic reaction that separates molecules of H2O, releasing bubbles of hydrogen on one electrode and oxygen on the other.
In these devices, each electrode is embedded with a different
catalyst, typically platinum and iridium, two rare and costly metals.
But in 2014, Stanford chemist Hongjie Dai developed a water splitter made of inexpensive nickel and iron that runs on an ordinary 1.5-volt battery.
In the new study, Cui and his colleagues advanced that technology further...
Full article and video: http://www.kurzweilai.net/water-splitter-produces-clean-burning-hydrogen-fuel-24-7
Under visible light illumination, the nanoscale photocatalysts perform the water-splitting reduction half-reaction with 100% efficiency. Credit: Lilac Amirav, Technion-Israel Institue of Technology
