Synthesis of Microcrystalline Hematite and Magnetite in Organic Solvents and Effect of a Small Amount of Water in the Solvents.

Microcrystalline magnetite (Fe3O4) particles having diameters of 7-34 nm were synthesized by thermal treatment of iron(III) acetylacetonate in organic solvents at high temperatures (423-573 K) and under autogenous pressures of the solvents. When the treatment was conducted in 1-propanol containing a small amount of water (1-3 vol%), nanosized hematite (α-Fe2O3) crystallized, which then was reduced to magnetite after a prolonged reaction time, indicating that a small amount of water in 1-propanol drastically changed the reaction mechanism for the formation of iron oxides.