Mössbauer investigation of magnetite nanoparticles incorporated in a mesoporous polymeric template

Mossbauer spectroscopy was used in this study to investigate magnetite-based nanocomposites, using mesoporous styrene-divinylbenzene (Sty-DVB) microspheres as the hosting template. The magnetite content was increased in the polymeric template by performing several in situ chemical reactions (one to six cycles) in the hosting material. We found the Mossbauer linewidth associated to site-A increasing with the relative increase of iron in site-A. The Mossbauer linewidth associated to site-B decreases with the relative decrease of iron in site-B. We explain our findings by assuming local change in the homogeneity associated to changes in the relative iron population in sites A and B.