Papers by Author: S.V. Tsybulya

Abstract: Strontium cobaltite doped with Fe and Nb, SrCo0.6Fe0.2Nb0.2O3−z, with perovskite-like structure, being one of the promising materials for oxygen permeable membrane implementation, has been investigated via in situ high temperature X-ray powder diffraction on Bruker D8 Advance instrument and high-resolution powder diffraction at synchrotron radiation beamline. The oxygen outlet from the lattice has been found to stay in correlation with the structural rearrangement forming two phases with different oxygen deficiency. The activation energy of phase splitting process has been estimated to be Eactivation ≈ 0.63 ± 0.06 eV.

Abstract: Software for the simulation of X-ray powder diffraction (XRPD) patterns for ultrafine-grained materials with some kinds of imperfections has been developed. These calculations are performed on the base of the model of one-dimensionally disordered (1D-disordered) crystal [1]. Such a model can describe stacking faults (SF) and other planar defects (PD) and also finite size of coherently scattering domains. Simulated XRPD pattern is compared with experimental one and can be fitted to it. Potentialities of the software are illustrated by several examples.