Materials of the hollandite structure in the K₂O–MeO(Mе₂O₃)–TiO₂ (Ме = Al, Ni, Mg) system, synthesized by two methods (solid-phase synthesis and pyrolysis of citrate–nitrate compositions), were studied. The pyrolysis, compared to the traditional solid-phase synthesis, yielded the materials with the more developed specific surface and, as a consequence, enhanced performance in sorption of a model dye, Methylene Blue (for K₂MgTi₇O₁₆, q = 18.75 mg g^–1). The K₂Al₂Ti₆O₁₆ sample, also prepared by pyrolysis, showed the highest catalytic performance in oxidation of СО and Н₂. The hydrogen oxidation on this catalyst occurred to 95% at 355°С with the performance of ~0.21 × 10^–5 mol g^–1 s^–1, which is two times higher compared to the sample of the same composition prepared by the solid-phase method. The hollandites show promise as sorbents and catalysts for gas treatment.

A metamaterial based on periodic ferroelectric inhomogeneities in a magnetic ferrite matrix including a quantity of ferroelectric composite in a matrix, demonstrating relative low microwave losses and effective dielectric permittivity, was produced. Glass-ceramic composites, consisting of low-melting glass and barium-strontium titanate, were successfully synthesized and incorporated into the periodic holes of the ferrite matrix to build the meta-structure. Investigation of the structure showed dielectric permittivity, which increased with the volume of ferroelectric inclusions. The range of magnetically controlled interactions of the meta-structures with an electro-magnetic field was increased for the matrix with periodic holes filled by the ferroelectric composite in comparison with the basic ferrite matrix. The ferrite substrate completely determined the microwave losses of the sample and the ferroelectric inclusions increased the Q-factor of the meta-structure.

The influence of composition of glycine–nitrate systems on the completeness of the formation of solid solutions of barium–strontium metatitanate was studied. It was shown that the decomposition of all studied glycine–nitrate compositions starts at 180°C; however, its character depends on the glycine content and composition’s pH value. The volume combustion mode obtained by exceeding the content of the reducing agent over the oxidant in composition provides the optimum conditions for the formation of single-phase products. Such compositions allow obtaining nanoscale powders of Ba_{1 – x}Sr_xTiO₃ solid solutions (0 ≤ x ≤ 0.4) by calcination at 550°C and introducing them into the composites based on porous magnetic glass, avoiding the interaction between the forming ferroelectric phase and glass matrix.