Hydrogen peroxide is one of the world's most versatile and widely used chemicals. A powerful oxidizing agent, H2O2 is commonly used as a bleach, an antiseptic and a disinfectant.
Despite its importance, however, says Christopher J. Kiely, hydrogen peroxide has eluded the best efforts of the chemists seeking a more direct, efficient and environmentally friendly means of producing it.
"Hydrogen peroxide has for decades been made by an indirect energy-intensive process," says Kiely, a professor of materials science and engineering at Lehigh University.
There are other disadvantages, Kiely adds. The economics of the current production method requires H2O2 to be produced in large quantities and in solutions with concentrations much higher, and less stable, than those used in most practical applications. This necessitates storage and transporting, which can be hazardous.
Chemists have searched nearly a century for a catalyst that can directly combine hydrogen and oxygen to produce H2O2. They have had some luck with palladium, says Kiely, but their efforts have been foiled by a second problem as fast as H2O2 is produced, it can decompose to water in the presence of the catalyst.
Now, a group of chemists and materials scientists from the UK and the U.S. is reporting that a carefully tailored alloy of palladium and gold nanoparticles catalyzes the direct production of H2O2 while "switching off" the decomposition of the compound. The breakthrough, which culminates more than five years of research on the topic, promises to enable the on-site production of H2O2 in smaller quantities and more desirable concentrations.
In an article in the Feb. 20 issue of Science, one of the world's foremost science journals, the group says the decomposition of H2O2 can be great
|Contact: Kurt Pfitzer|