Hexagonal OsB2 reduction upon heating in H-2 containing environment

    Authors

    Z. L. Xie; R. G. Blair; N. Orlovskaya;E. A. Payzant

    Comments

    Authors: contact us about adding a copy of your work at STARS@ucf.edu

    Abbreviated Journal Title

    Adv. Appl. Ceram.

    Keywords

    Osmium diboride; Redox stability; Hydrogen; SUPERHARD RHENIUM DIBORIDE; OSMIUM DIBORIDE; MECHANICAL-PROPERTIES; COMPOSITES; PRESSURE; BEHAVIOR; POWDER; ZRB2; Materials Science, Ceramics

    Abstract

    The stability of hexagonal ReB2 type OsB2 powder upon heating under reforming gas was investigated. Pure Os metal particles were detected by powder X-ray diffraction starting at 375 degrees C and complete transformation of OsB2 to metallic Os was observed at 725 degrees C. The mechanisms of precipitation of metallic Os is proposed and changes in the lattice parameters of OsB2 upon heating are analysed in terms of the presence of oxygen or water vapour in the heating chamber. Previous studies suggested that Os atoms possess (0) valence, while B atoms possess both (+3) and (-3) valences in the alternating boron/osmium sheet structure of hexagonal (P63/mmc, No. 194) OsB2; if controllable method for Os removal from the lattice could be found, the opportunity would arise to form two-dimensional (2D) layers consisting of pure B atoms.

    Journal Title

    Advances in Applied Ceramics

    Volume

    114

    Issue/Number

    2

    Publication Date

    1-1-2015

    Document Type

    Article

    Language

    English

    First Page

    114

    Last Page

    120

    WOS Identifier

    WOS:000351084400008

    ISSN

    1743-6753

    Share

    COinS