Zeolites are crystalline materials with nano-scale pores that are widely used in industry. Almost all the reported molecular-scale characterizations of zeolite-supported catalysts were obtained indirectly by spectroscopic methods.  Local atomic-scale structural information is lacking because imaging of zeolites by electron microscopy has been limited by beam damage.  We now show how to use aberration-corrected scanning transmission electron microscopy (STEM) to image isolated heavy metal atoms and small metal clusters in zeolites. The images with high signal-to-noise ratio were obtained under high-dose conditions; the locations of the metal atoms and clusters were determined directly for samples including cationic gold complexes in zeolite NaY.  This and related samples were also characterized by complementary spectroscopic methods including EXAFS and IR and tested for reactions of small molecules, such as CO oxidation.

Atomic-scale characterization of zeolite-supported metal complexes and metal clusters by aberration-corrected scanning transmission electron microsocopy

243rd National Meeting (2012)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.