Dutch researchers have found a new use for scanning tunneling microscopes: visualizing individual catalysts at work at a solid-liquid interface.
Johannes Elemans and colleagues at Radboud University said their new method could eliminate the process of measuring the ensemble properties of a large number of molecules.
The researchers formed arrays of large flat organic molecules, known as porphyrins, on a gold surface. The metal atom at the center of each porphyrin can react with oxygen to form a catalytic site, which can be used to convert one type of organic compound (an alkene) into another (an epoxide).
Using a scanning tunneling microscope, the team "watched" individual porphyrins at each step of the process. That offered a unique insight into how such reactions work at the single-molecule level, revealing information about catalyst activity, stability and distribution across the surface.
The method is detailed in the current issue of the journal Nature Nanotechnology.
Copyright 2007 by United Press International
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