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Mesoporous maghemite γ-Fe2O3 was obtained by thermal decomposition of iron citrate xerogel hydrate. The influence of precursor molar concentration and calcination temperature on the material phase composition, morphology, crystalline and magnetic microstructure, surface condition and optical properties was studied. The model of mesoporous γ-Fe2O3 formation is proposed. Obtained maghemite was tested as cathode material for lithium power sources. Increase of lithium power sources specific capacity and energy with the samples specific surface area enlarging is determined. Two kinetic processes are observed during discharge processes: lithium accumulation at the cathode material/electrolyte interface and diffusion of lithium ions into the material crystal structure. The diffusion coefficients of lithium in the cathode material on the different stages of discharge process are calculated.

We have proposed and experimentally tested a phenomenological model of nucleation of a specific polymorphic phase of titanium dioxide (anatase, rutile, brookite) resulting from the interaction of Ti 4+ hydroxocomplexes at different pH values of reaction medium. The degree of hydrolysis was determined as a function of pH for the monomers formed during the hydrolysis of titanium tetrachloride. Mixtures of anatase and brookite with an average size of coherently scattering domains of 5 nm and particles of ellipsoidal shape were obtained by precipitation at pH = 8. At the same time, nanoparticles of rutile with rod-like morphology and an average size of 10 nm were obtained at a pH = 1.

The phenomenological model of sulphate anions effect on the nanodispersed titania synthesis during hydrolysis of titanium tetrachloride was studied. It was proposed that both chelating and bridging bidentate complexes formation between sulphate anions and octahedrally coordinated [Ti(OH)h(OH2)6−h](4−h)+ mononers is the determinative factor for anatase phase nucleation.