Synthesis of Rare Earth Iron-Mixed Oxide Nanoparticles by Solvothermal Methods

摘要

We investigated the effects of starting materials, solvents, and amine additives on solvothermal reaction of the rare earth (RE) compounds with iron (III) compounds. Hexagonal YbFeO_3 was formed by the solvothermal reactions of ytterbium acetate and iron acetylacetonate in the absence and presence of amines. On the other hand, the solvothermal reaction of Yb chlorides and iron acetylacetonate in 1,4-butanediol in the presence of 1,6-hexane-diamine (N/Cl = 15) yielded orthorhombic YbFeO_3 (o-YbFeO_3) having a perovskite structure. o-YbFeO_3 crystals were also formed by the reaction in 1,5-pentanediol and 1,6-hexanediol. The crystallite sizes of o-YbFeO_3 obtained by the reaction in 1,5-pentanediol and 1,6-hexanediol were 59 and 49 nm, respectively, which were much smaller than that obtained in 1,4-butanediol (76 nm). XRD-pure orthorhombic REFeO_3 phases for Dy-Er with small ionic sizes were synthesized by the solvothermal reactions of RE chlorides and iron acetylacetonate.