Iron oxide sols structure

Han, Y.-S. and Choy, J.-H. (1998) Modification of the interlayer pore structure of silica iron oxide sol pillared clay using organic templates. /. Mater. Chem., 8,1459-1463. 

Polymer-inorganic composites with 25 mol% Fe on a cation basis were prepared using a sol of GLYMO and Al(OsBu)3 mixed with a solution of the structure-directing PI-/7-PEO diblock copolymer (see Table 21.1, F and G) and iron(m) ethoxide powder. For the production of a crystalline magnetic iron-oxide phase, the as-made composites were calcined at elevated temperatures in air. SAXS and TEM were performed to determine the structure and order in the materials. Figure 21.17a shows SAXS data for the pure diblock copolymer (1), the as-made polymer-inorganic composite (2), and material calcined to 750°C (3). 

In the present, work we propose the preparation of Y-Fez03-Si02 nanocomposite through individual sols of iron oxide and SiOz. This approach provides wide possibilities to control the structure of the composite [3]. Structural features and magnetic properties of the samples are reported. 

Iron-gray, ductile, malleable metal face -cen tered cubic structure at room temp. Stable in dry air, but superficially oxidized in moist air when finely divided may ignite sponta -neously. d 6.77. mp 795". E (aq) Cei+ /Ce — 2,48 V (calc). Slowly dec by cold, rapidly by hot water sol in dil mineral adds. Ceric salts usually are yellow to orange-red in color tnd liberate iodine from KI. Cerous salts are usually white tnd give a white ppt with alkali hydroxides or sulfides, insol ineicess of reagent they also are pptd by ammonium oxalate from cold dil acid sols. 

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