Nanoparticles of Co in the structure of impregnated ZSM-5 zeolites.

PAULA G. BERCOFF, HÉCTOR R. BERTORELLO, CLARA SAUX, LILIANA B. PIERELLA

Buenos Aires

Conferencia; At the Frontiers of Condensed Matter IV; 2008

We report the main results on the Co distribution over a ZSM-5 zeolite (MFI struture) with 2:8% of cobalt ions incorporated by wet impregnation, as determined by using scanning electron microscope (SEM) in both secondary (SE) and transmission (STEM) modes and Energy Dispersive Spectroscopy (EDS). Each size distribution of Co particles originates a different contribution to the magnetization giving a ferromagnetic behavior in a wide range of temperatures, to which superparamagnetic contributions from the smallest particles are superimposed.