Ce(Salen) complexes have been entrapped in the supercages of zeolite Y and the redox properties of thesezeolite-encapsulated complexes were investigated by cyclic voltammetry with graphite electrodeconfiguration in buffer phosphate solution.Two major observations are reported: (i) the electrochemical behavior of the zeolite-occluded complexes arises intwo different potential ranges, which can be related to different complex configurations and/or environment and (ii) the highstability of the faradaic responses leads to the conclusion that a pure extra-zeolite electron transfer mechanism in whichion-exchange with electrolyte cations frees the zeolite-occluded complexes to diffuse away from the working electrode and into solution cannot be operative