ISSN 0040-5795, Theoretical Foundations of Chemical Engineering, 2010, Vol. 44, No. 5, pp. 778–781. © Pleiades Publishing, Ltd., 2010. Original Russian Text © T.N. Patrusheva, S.D. Kirik, L.I. Kveglis, S.V. Komogortsev, K.P. Polyakova, A.I. Khol’kin, R.B. Abylkalykova, 2010, published in Khimicheskaya Tekh- nologiya, 2010, Vol. 11, No. 2, pp. 79–83. 778 INTRODUCTION The creation of uniform porous matrices from dif- ferent materials and the formation of heterostructures by filling porous matrices with functional materials is one of the actively developing fields of nanotechnol- ogy. The most widespread functional materials are the magnetic materials currently used in various fields of technology [1]: power supplies; interference filters; electricity meters; telecommunications equipment; electromotors; scientific equipment, including devices for studying the electromagnetic field of human brain; etc. The creation of SHF systems with fast-controlled parameters and systems whose charac- teristics differ in the different directions of the propa- gation of the microwave electromagnetic field (non- mutual systems) is impossible without ferromagnetic dielectrics (ferrites). The parameters of ferrites have been improved since their discovery in the late 1990s, and new materials are being synthesized to meet the requirements of SHF devices. Among ferrites belonging to ferromagnetic semi- conductors from the oxide group, the most widely used materials are barium ferrite BaO ⋅ 6Fe 2 O 3 , cobalt ferrite CoO ⋅ Fe 2 O 3 , and strontium ferrite SrO ⋅ 6Fe 2 O 3 . The properties of ferrites are listed in the table in comparison with the properties of a samarium– cobalt magnet. Cobalt ferrite CoFe 2 O 4 with a spinel structure hav- ing uniaxial anisotropy possesses a high coercive force. Uniaxial anisotropy is achieved in nanosized materials or by processing a material in a magnetic field [2]. As is known, magnetization and magnetic anisotropy in nanoparticles can be markedly higher than in large crystalline particles, and the differences in the Curie and Neel temperatures can reach hundreds of degrees. Due to this, materials containing nanoparticles can be used in data recording and storage systems, new per- manent magnets, magnetic cooling systems, as mag- netic sensors, etc. When ferrites are used in powerful SHF devices, it is necessary to take into account the magnetic losses related to spin wave excitation at high power levels. These losses are characterized by the line width of spin waves, DHk. The larger the DHk, the higher the stability of ferrite against the action of SHF power. For grains of less than 1 μm, DHk increases by a factor of 3–5 as compared with the DHk for large grains. To obtain nanosized complex oxide materials, it is recommended to use solution technologies that pro- vide the formation of many centers of crystallization Nanosized Cobalt Ferrite Powders Obtained by Pyrolytic Extraction T. N. Patrusheva a , S. D. Kirik a , L. I. Kveglis b , S. V. Komogortsev b , K. P. Polyakova, A. I. Khol’kin c , and R. B. Abylkalykova d a Siberian Federal University, Krasnoyarsk, Russia b Kirenskii Institute of Physics, Siberian Branch, Russian Academy of Sciences, Krasnoyarsk, Russia c Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Moscow, Russia d West Kazakhstan Technical University, Ust’-Kamenogorsk, Kazakhstan e-mail: kholkin@igic.ras.ru; pat55@mail.ru Received February 18, 2009 Abstract—Heterostructures were prepared from MSM molecular sieves and magnetic materials by extraction pyrolysis. The molecular sieves were filled with solutions of extracts and heated to remove the organic phase and form an inorganic material. The annealing and dissolution of the MSM-41 molecular sieve gave nano- sized cobalt ferrite powder with particles of 40 nm and a coercive force 5000 Oe. Key words: extraction pyrolysis, cobalt ferrite, nanosized powders, MSM matrix, magnetic properties. DOI: 10.1134/S0040579510050234 NANOTECHNOLOGIES AND NANOMATERIALS Magnetic properties of ferrites Material grade Basic composition B r × 10 –3 , G H c , Oe (BH) max , MG Oe Co ferrite CoO ⋅ Fe 2 O 3 3 1800 2 Ba ferrite BaO ⋅ Fe 2 O 3 (isotropic) 2 1700 1 Ba ferrite BaO ⋅ Fe 2 O 3 (anisotropic) 3.7 2000 3.2 Sr ferrite SrO 6 ⋅ Fe 2 O 3 (anisotropic) 3.6 3200 3 Co 5 Sm Co 5 Sm (anisotropic) 9.4 8500 21 Note: B r is the residual induction, H c is the coercive force, and (BH) max is the maximum energy.