| Abstrakt: |
This work presents the results of studies aimed at determining the conditions for the synthesis of a new heterometallic complex of Co(II) and Nd(III) with oxalic acid in the presence of 1,10-phenanthroline, studying its composition, structure, thermal properties and its ability to form complex oxides. The hetero- and monocomplexes [Co(C2O4)·Phen]2·4H2O, [Nd2(C2O4)3·2Phen], [Co2Nd2(C2O4)5·2Phen]·4H2O (Phen -- phenanthroline) were synthesized. The complexes were investigated by the following physicochemical research methods: elemental analysis, differential thermal analysis, IRand diffuse reflection electronic spectroscopies, and X-ray powder diffraction. Based on the analysis of electronic and IR spectra, it was shown that ions of metals bind bidentately with ions of oxalates and with molecules of 1,10-phenanthroline. The structures of the ion of cobalt and ion of neodymium correspond to the distorted octahedron. The ions of metals are bound together by oxalate ligands. The powders of oxides were prepared by thermolysis of the heterocomplex up to 800 °C and 1000 °C. The composition of the obtained oxide powders was controlled by X-ray powder diffraction. When the heterocomplex is heated to 800 °C, in addition to the complex oxide NdCoO3, we obtained the following oxides: Nd2O3 (hexagonal crystal system), Nd2O3 (cubic crystal system) and Co3O4 (cubic crystal system). After heating to 10000C, a more pure complex oxide NdCoO3 was obtained. Neodymium cobaltate NdCoO3 crystallizes in the cubic crystal system, the unit cell parameter is a=3.770 Å, the cell volume is 53.568 Å3. The average crystallite size was calculated using the Scherrer formula, and it is equal to ~35 nm. The synthesized heterometallic complex [Co2Nd2(C2O4)5·2Phen]·4H2O can be used as a precursor for the preparation of cobaltate of neodymium with lower energy consumption than in solidphase synthesis. [ABSTRACT FROM AUTHOR] |
