Write your abstract here. Scientists Find a New Way to Make Water―Fuels Hope for Green Tech.
Scientists have
found a radical new way of making water that could
substantially lower costs for green technology. The University of
Illinois researchers have unlocked the trick to making water from
unlikely starting materials, such as alcohols. They are expecting their
discovery to lead to better catalysts and less expensive fuel cells. "We found that unconventional metal hydrides can be used for a chemical
process called oxygen reduction, which is an essential part of the
process of making water," said Zachariah Heiden, a doctoral student and
lead author of a paper accepted for publication in the Journal of the
American Chemical Society. A water molecule is composed of two
hydrogen atoms and one oxygen atom.
However, you can''t simply take two hydrogen atoms and stick them onto
an oxygen atom. The actual reaction to make water is a bit more
complicated: 2H2 + O2 = 2H2O + Energy. Basically, the equation says: To produce two
molecules of water (H2O),
two molecules of diatomic hydrogen (H2) must be combined with one
molecule of diatomic oxygen (O2) and that energy will be released in
the process. "This reaction (2H2 + O2 = 2H2O + Energy) has been known for two
centuries, but until now no one has made it work in a homogeneous
solution," said Thomas Rauchfuss, a U. of I. professor of chemistry and
the paper''s corresponding author. The well-known reaction also describes what happens inside a hydrogen
fuel cell where the diatomic hydrogen gas enters one side of the cell,
diatomic oxygen gas enters the other side. The hydrogen molecules lose
their electrons and become positively charged through a process called
oxidation, while the oxygen molecules gain four electrons and become
negatively charged through a process called reduction. The negatively
charged oxygen ions combine with positively charged hydrogen ions to
form water and release electrical energy. "Most compounds react with either hydrogen or oxygen, but this catalyst
reacts with both," Heiden said. "It reacts with hydrogen to form a
hydride, and then reacts with oxygen to make water; and it does this in
a homogeneous, non-aqueous solvent." They are hopeful that these new catalysts will lead to eventual
development of more efficient hydrogen fuel cells, substantially
lowering their cost. Galaxy News Reported November 1st, 2007.