Influence of nitrogen flow during sintering of bismuth manganite ceramics on grain morphology and surface disorder. (2nd January 2017)

• Record Type: Journal Article
• Authors: Pilch, M.; Molak, A.; Koperski, J.; Zajdel, P.
• Is Part Of: Phase transitions. Volume 90:Number 1(2017)
• Page Start: 112
• Page End: 124
• Publication Date: 2017-01-02
• Subjects: Bismuth manganite -- nitrogen -- resistivity -- SEM -- XPS -- XRD; Phase transformations (Statistical physics) -- Periodicals; 530.47405
• DOI: 10.1080/01411594.2016.1219737
• Languages: English
• ISSNs: 0141-1594

Abstract

ABSTRACT: Bismuth manganite ceramics, consisted of two phases: cubic I23 and orthorhombic Pbam, were obtained by high-temperature sintering in the air. The powdered ceramics were sintered in gaseous nitrogen flow at stabilized temperature of TS = 870–1120 K for 4 h. Grain structure and chemical composition were checked by scanning electron microscopy (SEM). We observed changes in the grain shapes, the number and size of the hexagon-based parallelepipeds increased. The X-ray diffraction (XRD) test has shown that the orthorhombic BiMn2 O5 phase formation was favored. The local disorder was tested by X-ray photoemission spectroscopy. Multi-component lines assigned to O 1s, Mn 2p, Bi 4f were detected. The ratio of intensities of particular components was influenced by the sintering conditions. The shape of valence band was not influenced by the sintering conditions. Electric resistivity was measured in 200–750 K range with the use of Ag and In electrodes. The activation energy increased slightly when the sintering temperature increased.