Structure and Properties of Nanostructured YBa2Cu3O7–δ, BiFeO3, and Fe3O4

The development of new nanostructured materials based on YBa 2 Cu 3 O 7–δ , BiFeO 3 , and Fe 3 O 4 compounds is considered. The structure, morphology, and properties of these materials are studied. The possibilities of fabricating YBa 2 Cu 3 O 7–δ ceramics with given densities from nanopowders in a single stage by an energy efficient method and growing superconducting films of the same composition on a silicon substrate (on a SiO 2 layer) are demonstrated. The technique for fabricating BiFeO 3 nanopowder, making it possible to obtain nanostructured ceramics without additional accompanied phases commonly forming during BiFeO 3 synthesis is developed. Two methods of the single-stage synthesis of Fe 3 O 4 nanopowder are presented: burning of nitrate-organic precursors and the electrochemical three-electrode method in which one of the electrodes, i.e., an anode containing scrap iron and slurry, is used as an expendable material.