SYNTHESIS AND MORPHOLOGICAL FEATURES OF MATERIALS BASED ON IRON(III) AND COBALT(II) COMPOUNDS

Zeolite-like frame materials based on 2-ethylimidazolate of cobalt (II), iron (III) terephthalate and cobalt (II) terephthalate were synthesized using the direct mixing method and the solvothermic method. The obtained materials are characterized using a wide range of physico-chemical analysis methods. IR spectroscopy allowed us to obtain reliable conclusions about the formation of a metal-linker bond, which confirms the formation of coordination bonds in the organometallic framework for all synthesized samples. The formation of a pure phase of synthesized frame structures was established, which was recorded using the method of X-ray phase analysis. Characteristic peaks in the range from 8° to 32°, were observed on the X-ray images of all samples, the relative intensity and local location of which prove the formation of the pure phase of the corresponding ethylimidazolates and terephthalates. The study of the morphology of the materials showed that the samples are quite highly dispersed heterogeneous systems. The average particle size for a material based on 2-ethylmidazolate of cobalt (II) was 0.5-1 µm. Materials obtained by direct mixing are characterized by a spherical particle shape, while samples obtained by the solvothermic method are characterized by a cubic particle shape. For materials based on iron (III) and cobalt (II) terephthalates, the average particle size was 0.15-0.25 μm. The individual particles have the shape of a prism truncated on both sides. The parameters of the porous structure of the synthesized samples were found by the method of low-temperature nitrogen adsorption. The specific surface area (according to the BET method) and the pore volume are calculated for all materials. The specific surface area for different samples varies from 520 to 1100 m2/g. A sufficiently wide range of surface areas is due to the varying degree of aggregation when the ligand/metal ratio changes during synthesis. The results of physico-chemical studies of the structural and surface characteristics of synthesized samples confirm the fundamental possibility of their use as sorbents, in particular for the extraction of rare earth metal ions. For citation: Karaseva A.A., Diallo A., Filippov D.V., Vashurin A.S. Synthesis and morphological features of materials based on iron (III) and cobalt (II) compounds. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2025. V. 68. N 1. P. 77-84. DOI: 10.6060/ivkkt.20256801.7101.