The study of silver-zeolite samples by a combination of EXAFS and Diffuse Reflectance UV-Visible spectroscopy has been utilised to discover the effect of the structural type and Si/Al ratio of zeolite matrix as well as influence of reduction temperature on the size, structure and oxidation of silver species stabilised inside zeolite voids. The preparation of silver-zeolite samples at high temperature using mordenite with medium Bransted acid strength or at low temperature using mordenite with high acid strength leads to fast oxidation of reduced silver species. After reduction at medium temperatures silver clusters interpreted as Ag_8~0 and Ag_8~(δ+) are formed in mordenites with intermediate Bransted acid strength. The reduction of silver samples at high temperature utilising mordenite with a very small concentration of weak Bransted acid sites leads to the formation of amorphous Ag particles. Deformation of the eight-atom clusters is more prominent in the erionite cavities, where space is more severely restricted than in mordenite channels. It is proposed that the charged Ag_8~(δ+) clusters are more deformed than neutral Ag_8~0 clusters.
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