Zeolites Modified with Silver Nanoparticles and Clusters: Synthesis, Characterization, and Catalytic Performance in H2 and CO Oxidation Reactions

Abstract

Zeolites with Rho, Beta, and paulingite structures, modified with silver nanoparticles and clusters, are prepared, and their catalytic performances in hydrogen and carbon monoxide oxidation reactions are investiagted. The prepared zeolite samples have different silver loads (up to 25 wt %), and the loaded silver exists in the form of nanoparticles and clusters having a different nuclearity (\(\rm{Ag_8^+},\rm{Ag_4^{2+}},\rm{Ag_4^+}\)). Silver clusters were detected and identified using UV−Vis spectroscopy. It is established that the catalytic performance of our silver-modified zeolites varies with the silver load, the form the loaded silver assumes (nanoparticles and/or clusters of a different nuclearity, and their ratio), and the structural type of zeolite matrix.