Structural, thermal and transport properties of $$ {\text{B}}{{\text{i}}_4}{{\text{V}}_{2 - {\text{x}}}}{\text{G}}{{\text{a}}_{\text{x}}}{{\text{O}}_{11 - \delta }} $$ (0 ≤ x ≤ 0.4)

Abstract

Solid electrolytes are mostly used in solid oxide fuel cells (SOFC). In the present study, gallium-substituted compounds (Bi 4 V 2Àx Me x O 11Àd ; Me=Ga 3+ ; 0≤x≤0.4) were prepared by solid-state reaction technique for its use as an electrolyte in SOFC. Structural and conductivity behavior was studied as a function of the Ga 3+ substitution on vanadium site. The compounds remain in the orthorhombic α-phase for x=0 and 0.1 whereas higher concentration of dopant leads to β-phase stabilization. The highest and lowest ionic conductivity were observed in x=0.2 and x=0.4 samples, respectively. The prepared samples were studied by using alternating current conductivity, differential thermal analysis and X-ray diffraction techniques. The results are discussed on the basis of formation of oxygen vacancy and its ordering.

Optical, mechanical and TEM assessment of titania-doped Bi2V1−x Ti x O5⋅5−δ bismuth vanadate oxides

“…The selected area diffraction (SAED) patterns for the different grains of the same material have been analyzed to determine the lattice structure. In addition, these properties have been correlated to the conductivity of above-mentioned compounds, which has already been reported by our group (Kant et al 2008(Kant et al , 2009(Kant et al , 2010Kaur et al 2012aKaur et al , b, c, 2014. The as prepared samples are characterized using UV-Visible spectroscopy, Vicker's microhardness test and transmission electron microscopy (TEM).…”