Send to

Choose Destination
J Phys Chem B. 2006 Mar 23;110(11):5286-93.

New method for analysis of nanoparticle geometry in supported fcc metal catalysts with scanning transmission electron microscopy.

Author information

Haldor Topsøe A/S, Nymøllevej 55, DK-2800 Lyngby, Denmark.


To apply the knowledge of reaction mechanisms of heterogeneously catalyzed reactions on the atomic scale to supported catalyst systems, a detailed description of the structure of active particles on the atomic scale is required. In this article, a method is developed to construct atomic-scale geometric models for supported active fcc metal nanoparticles, based on a measurement of particle sizes and particle volumes by Scanning Transmission Electron Microscopy (STEM) and the M-M coordination number determined from EXAFS. The method is applied to supported Au/TiO(2), Au/MgAl(2)O(4)(-), and Au/Al(2)O(3) catalysts. These geometric models allow for estimation of geometric properties, such as specific Au surface area, metal-support contact perimeter, metal-support contact surface area, edge length, and number of Au atoms located at the corners of the particles, with an error on the order of 20%. In the three catalysts studied here we find that the Au particles in the Al(2)O(3) supported catalyst are small. The Au particles in the Au/TiO(2) catalyst are smaller in diameter than those for the Au/MgAl(2)O(4), but also thicker. The differences in particle size and shape seem to reflect the differences in the metal-support interface energy in the three catalyst systems.


Supplemental Content

Full text links

Icon for American Chemical Society
Loading ...
Support Center