In
a world first, Japanese researchers have produced a new alloy similar
to the rare metal palladium, a breakthrough that could help alleviate
the nation’s dependence on other countries for this resource.
The
alloy was produced with nanotechnology and has properties similar to
those of palladium, a rare metal located between rhodium and silver on
the periodic table of the elements.
Led by Prof. Hiroshi Kitagawa of Kyoto University, the research team also produced alternatives to other kinds of rare metals.
Rhodium
and silver molecules usually do not mingle, and remain separated like
oil and water even after melting at high temperatures. To mix the
elements, Kitagawa focused on a technique that produces ultramicroscopic
metal particles.
His
team created a solution containing equal quantities of rhodium and
silver, turned the solution into a mist and mixed it little by little
with heated alcohol to produce particles of the new alloy. Each particle
is 10 nanometers in diameter and atoms of the two metals are equally
mixed.
The
new alloy has the same properties as palladium, which is used as a
catalyzer to cleanse exhaust gas and absorbs large quantities of
hydrogen, the researchers said.
Rhodium,
palladium and silver have 45, 46 and 47 electrons, respectively,
numbers that determine their chemical characterizations.
“The
orbits of the electrons in the rhodium and silver atoms probably got
jumbled up and formed the same orbits as those of palladium,” Kitagawa
said.
The
new alloy will be difficult to produce commercially, but Kitagawa
intends to use the production method to develop other alloys for use as
alternative rare metals.
Kitagawa
has begun joint research with automakers and other companies, but said
he could not disclose any information because of patents and other
reasons.
Rare
metals exist only in small quantities and are economically difficult to
mine or extract. Because adding just a small quantity of rare metals
can change or improve the properties of other materials, rare metals are
called the “vitamins” of industry.
For example, palladium is essential for making electronic parts, and lithium is used to produce batteries.