New high-yield preparation procedure of Ln[Fe(CN) 6]· nH 2O (Ln = La, Gd, and Lu) and their thermal decomposition into perovskite-type oxides

Abstract

The heteronuclear Ln[Fe(CN) 6]· nH 2O (Ln = La, Gd, and Lu) complexes were synthesized by the mixing of (NH 4) 3[Fe(CN) 6] and Ln(NO 3) 3 methanol solutions as a new method. Their thermal decomposition products were then investigated. Although the yield of the Ln[Fe(CN) 6]· nH 2O complexes was ca. 20% for the well-known method in a water solution, it was improved to ca. 90% using this new method. The X-ray diffraction (XRD) patterns of the complexes agreed with those of the Ln[Fe(CN) 6]· nH 2O single phase for all the examined Ln systems. The LnFeO 3 single phase was obtained by the thermal decomposition of the synthesized heteronuclear complexes for Ln = La, Gd, and Lu.