NANOCOMPOSITES CONTAINING NANOCLUSTERS OF FE2P OR GAMMA-FE2O3

Covalent incorporation of an organoiron complex into a silica xerogel matrix affords a single-source precursor for two different nanocomposi te materials. Thermal treatment of this molecularly doped xerogel unde r hydrogen produces a nanocomposite containing nanocrystals of Fe2P (b arringerite). Thermal treatment of this doped xerogel under oxidizing conditions gives a nanocomposite containing nanocluster of gamma-Fe2O3 (maghemite-Q). The latter result is unique in that thermal treatment of silica xerogels doped with ferric ions under similar thermal condit ions affords an undesired iron silicate, Fe2SiO4 (fayalite), as the pr inciple product. Preliminary magnetization measurements indicate that both nanocomposites exhibit interesting magnetic properties.