Conditions of Cobalt(II) Ferrite Preparation on the Surface of Biochar

We report a detailed study of the influence of the amount of ammonia and citric acid added as precursors and the nature of a biochar support on the formation of cobalt(II) ferrite-based composite materials in sol–gel synthesis. The materials thus prepared have been characterized by X-ray diffraction and electron microscopy, and we evaluated the crystallite size in them by the Scherrer method. We have optimized the amounts of the precursors and demonstrated that the morphology of the composite materials is determined by the shape of the biochar support particles. The results of this study can be helpful in developing a process for the fabrication of organic–inorganic composite materials with structure-sensitive properties.