Manganese-doped bismuth vanadate solid electrolytes

Abstract

The solid solution series Bi ₂ V _1-x Mn _x O _5.5-x (0.10≤x≤0.25) has been prepared by conventional solid-state reaction and by crystallization from the melt. After additional subsolidus annealing both procedures yielded tetragonal phases with similar structures and lattice constants, as determined by X-ray powder diffraction. Partial substitution of manganese on the vanadium sites stabilizes Bi ₂ V _1-x Mn _x O _5.5-x in the high-temperature tetragonal (γ) structure of Bi ₂ VO _5.5 for compositions in the range 0.10≤x ≤0.25. The structures of four compositions have been investigated by combined Rietveld refinements of X-ray and neutron powder diffraction data. Further characterization studies by transmission electron microscopy, magnetic susceptibility measurements and differential thermal analysis are described.