Nanoclusters of various sizes and chemical compositions are of great interest as catalysts because of the high surface areas that they present to encourage chemical reactions to occur. The emerging ability to control the sizes of these clusters to atomic precision affords new opportunities for designing novel catalysts. From Brookhaven National Laboratory, via AAAS EurekAlert “Controlling the Size of Nanoclusters: First Step in Making New Catalysts“:
Researchers from the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory and Stony Brook University have developed a new instrument that allows them to control the size of nanoclusters — groups of 10 to 100 atoms — with atomic precision. They created a model nanocatalyst of molybdenum sulfide, the first step in developing the next generation of materials to be used in hydrodesulfurization, a process that removes sulfur from natural gas and petroleum products to reduce pollution.
As reported in the July 9, 2008 online edition of the Journal of Physical Chemistry C [abstract], the scientists made size-selected molybdenum sulfide nanoclusters as gaseous ions, and then gently deposited the clusters on a gold surface. The nanoclusters interact weakly with the gold support and therefore remain intact.
“With this new instrument, we can control how many and what type of atoms are in a nanocluster,” said Brookhaven chemist Michael White, the principal author of the paper. “This knowledge enables us to make nanoclusters with predetermined size, structure and chemical composition, all which are important for the design of new catalysts.”
—Jim