Collect. Czech. Chem. Commun. 1992, 57, 817-825

Formation of Reactive Clusters in Pd-Y Zeolite by Reduction-Reoxidation Treatment

Hiroshige Matsumoto and Shuji Tanabe

Department of Chemistry, Faculty of Liberal Arts, Nagasaki University, Bunkyomachi 1-14, Nagasaki, Japan


Preparation of a finely dispersed Pd-Y zeolite has been investigated by temperature-programmed reduction (TPR) and extended X-ray absorption fine structure (EXAFS) techniques. Upon the treatment by a sequence of calcination, reduction, and reoxidation, the original Pd(NH3)42+ ions in the zeolite transformed to reactive species, which were reduced with hydrogen at room temperature and characterized as small PdO clusters of about 25 Pd atoms.