Cation-Cation Interaction in Dehydrated Zeolites X and Y Monitored by Modulus Spectroscopy

We report impedance measurements on zeolites NaX and NaY. By means of a new evaluation technique, i.e., the modulus master plot technique, two distinct relaxation processes within one spectral presentation could be visualized, a local dipolar relaxation and a long-range charge carrier process. The corresponding activation energies reflect the enhanced cation-cation interaction in NaX, which results from the smaller Si/Al ratio causing a larger number of occupied cation sites per unit cell. This demonstrates that from the macroscopic impedance response one can deduce to elementary processes on the microscopic scale, when structural details are taken into account.[PUBLICATION ABSTRACT]