Cobalt (II) Ferrite-Based Organic-Inorganic Composite Material Formation and Its Properties.

This paper examines the formation of cobalt (II) ferrite on the surface of an organic support in stages: mixing metal salts, interaction with ammonia and citric acid solutions, and the subsequent thermolysis of the intermediate products. The resulting materials were characterized by X-ray diffraction, electron microscopy, and elemental analysis. A comparative analysis of the materials' morphological properties suggests the formation of a cobalt (II) ferrite film on the surface of the organic support. This film forms as small cubic crystals measuring 50-100 nm in size, with a simultaneous significant (2-5 times) increase in the specific surface area of the synthesized composite materials compared to the support surface. The typical pore diameter of the composites is 20-40 nm. The synthesized material of CoFe2O4/sunflower husk biochar exhibits high catalytic activity; dye is removed from the solution within 60 min. The material of CoFe2O4/sunflower husk ash is less active in this process: dye removal is observed 140 min after the start of the reaction. These data may be useful for developing catalytically active materials for wastewater and soil solution treatments to remove persistent pollutants.