IRON-CONTAINING NANOCOMPOSITES BASED ON ZSM-5 ZEOLITE

Abstract

Here we report synthesis and investigation of Fe /ZSM-5 magnetic nanocomposites. Intercalation of iron was performed by ion-exchange procedure and by impregnation of ZSM-5 zeolite in H + form by Fe ( CO )5. Magnetic nanocomposites were prepared by thermal treatment of impregnated samples in hydrogen flow at different temperatures. Chemical composition, structure and physical properties of the samples were characterized by chemical analysis, TGA, XRD, TEM, Mössbauer spectroscopy and SQUID magnetization measurements. Nanocomposites prepared by reduction of cation-exchanged zeolite indicate paramagnetic behavior even at 4 K. Repeatable ion-exchange/reduction procedure used to enrich ZSM-5 matrix with iron led to formation of bulk iron. Fe /ZSM-5 nanocomposites prepared by thermal decomposition of Fe ( CO )5 in the channels of ZSM matrix reveal their ferromagnetic behavior even at room temperature. The coercivity at 300 K for annealed samples attain 670 Oe for the crystallization temperature of 450°C. According XRD, TEM and Mössbauer data iron nanoparticles were formed in the cavities of zeolite.