NEW STRUCTURAL AND ELECTRICAL DATA ON Bi-Mo MIXED OXIDES WITH A STRUCTURE BASED ON [Bi12O14] infinity COLUMNS

摘要

We recently described a new family of oxide anion conductors with a structure based on [Bi12O14] infinity columns. The parent compound of this series can be formulated as Bi26Mo10O69 and formation of a solid solution, in the Bi2O3-MoO3 binary system, in the range 2.57 less than or equal to Bi/Mo less than or equal to 2.77 was established. The stoichiometry of this series was questioned but confirmed. The first part of this paper is devoted to a refutation of criticisms. In the second part, a comparison with other Bi2O3-based oxide anion conductors enables us to propose an iono-covalent description of this novel structure type, taking into account all the structural and electrical features, especially new neutron powder diffraction refinement and conductivity measurements under variable pO2s. 38 refs.