Fuel cell technology gets a boost
In an impetus for fuel cell technology to build "smart" cars, scientists at Stanford University have developed a low-cost, emissions-free device that uses an ordinary AAA battery to produce hydrogen by water electrolysis.
The battery sends an electric current through two electrodes that split liquid water into hydrogen and oxygen gas.
Unlike other water splitters that use precious-metal catalysts, the electrodes in the Stanford device are made of inexpensive and abundant nickel and iron.
"Using nickel and iron which are cheap materials, we were able to make the electrocatalysts active enough to split water at room temperature with a single 1.5-volt battery," explained Hongjie Dai, a professor of chemistry at Stanford University.
This is the first time anyone has used non-precious metal catalysts to split water at a voltage that low.
"It is quite remarkable because normally, you need expensive metals like platinum or iridium to achieve that voltage," Dai added.
Fuel cell technology is essentially water splitting in reverse.
A fuel cell combines stored hydrogen gas with oxygen from the air to produce electricity that powers the car.
The only byproduct is water - unlike gasoline combustion that emits carbon dioxide, a greenhouse gas.
In 2015, US consumers will finally be able to purchase fuel cell cars from Toyota and other manufacturers.
Although touted as zero-emissions vehicles, most of the cars will run on hydrogen made from natural gas - a fossil fuel that contributes to global warming.
"In addition to producing hydrogen, the novel water splitter could be used to make chlorine gas and sodium hydroxide, another important industrial chemical," researchers concluded.
The study appeared in the journal Nature Communications.
(Posted on 22-08-2014)