Nanoclusters of silver doped in zeolites as photocatalysts

Nanoclusters of silver and iron ions doped in Y zeolite and sodalite have been prepared. Photoluminescence spectra of Ag-Y zeolite, Ag/Fe2O3-Y zeolite, Ag-sodalite, and Ag/Fe2O3-sodalite were obtained from 4.5 to 298 K and revealed the formation of different kinds of silver clusters in the zeolite hosts. The amount of silver and iron in the corresponding material were determined using atomic absorption spectroscopy. The purity and unit cell structure of each catalysts was determined using X-ray powder diffraction analysis. It was found that while the structure of the support materials remained relatively intact after the incorporation of Ag+ and Fe3+ onto the supports, differences in the structure of the support corresponded with differences in cluster size and composition. It was also found that adding Fe2O3 to Ag-Y zeolite shifted the observed Ag cluster photoluminescence to longer wavelengths, while Ag-sodalite remains largely unaffected by the addition of Fe2O3. This further supports the conclusion that the structure of the support material plays a major role in cluster formation.