SYNTHESIS OF SrO AND BaO SUBMICROPARTICLES BY THE METHOD OF THERMAL DECOMPOSITION OF AEROSOLS

Abstract

In the paper submicroparticles of strontium oxide and barium oxide were obtained by thermal decomposition of aerosols. The nature of the synthesized compounds was proved by IR spectroscopy. The characteristic linear dimensions were determined and the surface morphology of the particles was studied by atomic force microscopy. Analysis of the obtained AFM-frames shows that the formed particles have a shape close to spherical, and their size varies in the range of 115-560 nm, depending on the initial concentration of precursors. It is shown that during the pyrolysis the splitting of a drop of liquid occurs, and the resulting solid phase is hollow spheres. The optical band gap of the particles of strontium and barium oxides was determined on the basis of their diffuse reflection spectra (DRS) along the edge of the main optical absorption band. It is in the ranges of 3.15-3.19 eV and 2.95-3.16 eV, respectively. We found a manifestation of the size effect associated with the interrelation of reducing the diameter of SrO and BaO particles and the narrowing of the characteristic absorption bands in the IR spectra, as well as the shift of the absorption edge in the DRS-spectra to the shortwave region, i.e. increasing the optical band gap. The data obtained are of interest in the further study of the properties of submicro- and nanostructures based on strontium oxide and barium oxide, as well as in the synthesis of new functional materials with improved complex properties.