Formation of Ag-Fe Bimetallic Nano-Species on Mordenite Depending on the Initial Ratio of Components

The formation and properties of silver and iron nanoscale components in the Ag-Fe bimetallic system deposited on mordenite depend on several parameters during their preparation. Previously, it was shown that an important condition for optimizing nano-center properties in a bimetallic catalyst is to change the order of sequential deposition of components; the order “first Ag(+), then Fe(2+)” was chosen as optimal. In this work, the influence of exact Ag/Fe atomic proportion on the system’s physicochemical properties was studied. This ratio has been confirmed to affect the stoichiometry of the reduction–oxidation processes involving Ag(+) and Fe(2+), as shown by XRD, DR UV-Vis, XPS, and XAFS data, while HRTEM, S(BET) and TPD-NH(3) show little change. However, it was found the correlation between the occurrence and amount of the Fe(3+) ions incorporated into the zeolite’s framework and the experimentally determined catalytic activities towards the model de-NOx reaction along the series of nanomaterials elucidated in this present paper.