The Factors Affecting Ionic Conductivity in La2Mo2–xVxO9–δ (0 ≤ x ≤ 0.100): XRD and Raman Studies

In this paper we report the structural and Raman spectroscopy analyses of La 2 Mo 2– x V x O 9–δ (0 ≤ x ≤ 0.100). Rietveld refined XRD patterns show that La-O1, La-O2, La-O3 and the average La-O bond length of lanthanum-oxygen polyhedral decrease with vanadium content. A clear correlation was found between ionic conductivities and Mo-O bond length variation with dopant concentration. The composition x = 0.050 had the shortest O2-O3 and O3-O3 bond lengths and the highest conductivity. The La-La-La angle of [O1LaMo] anti-tetrahedral unit is maximum at x = 0.050, allowing increased O2 and O3 ion mobilities. The Raman spectra shows, the Mo-O bond length alterations as a function of the doping concentration and are in good agreement with the results obtained from X-ray results.