Synthesis, thermal and electrical properties of Al-doped Bi4V1.8Cu0.2O10.7

A study on structural properties, conductivity and FT-IR spectroscopy of Cu–Al doubly substituted Bi4V2O11

“…This may be related to changes in local symmetry as claimed from both XRD results that indicate a decrease in cell volume and the activity changes in the FT-IR spectrum after substitution. At high temperature, samples with x ≤ 0.3 show activation energies in the range of 0.26-0.42 eV, as generally obtained for γ-type phases [3,[19][20][21][22]. However, the activation energy values obtained for x > 0.3 are unusually higher.…”

“…In a previous study, we have reported some data about double substitution of V 5+ by (Cu 2+ , Nb 5+ ) [20] and by (Cu 2+ , Co 2+ ) [21]. More recently, we have investigated the structural and ionic conductivity changes, when vanadium is doubly substituted by (Cu 2+ , Al 3+ ) in Bi4V1.8Cu0.2−yAlyO10.7+y/2 compounds [22]. We have shown an improvement in conductivity in spite of the decrease of the vacancies number in the anionic sublattice when y increases.…”

“…We have shown an improvement in conductivity in spite of the decrease of the vacancies number in the anionic sublattice when y increases. This reflects the significant effect of the double substitution in these materials (σ600 C=4.16 × 10 -2 S.cm -1 for Bi4V1.8Cu0.2O10.7 compound [18] and σ600 C=7.24 × 10 -2 S.cm -1 for Bi4V1.8Cu0.15Al0.05O10.725 compound [22]). In this context, it would be interesting to explore a larger domain of stability of the tetragonal phase for amounts of substitution of vanadium x≥0.20.…”

Effect of Simultaneous Cu and Nb Doping Bi4v2o11 on Structural and Electrical Properties of Bi4v2−Xcux/2nbx/2o11−3x/4

“…Hence, numerous solid solutions had been prepared by substituting vanadium (V 5+ ) by other metallic cations. These solid solutions constitute a family of compounds known by the acronym BiMeVOX (Me= Co, Cu, Mn, …) [11][12][13][14][15][16]. Generally, the α, β and γ forms are progressively stabilized by increasing the substitution rate.…”

“…According to dozens of works published in the literature, it can be concluded that the solid solution limits depend generally on the valence and the preferred coordination geometry of the substituent cation [17][18][19]. The best conductivity is always obtained when close to 10% of V 5+ in Bi4V2O11, has been substituted by 10% of the metal independently of its oxidation state and its nature [10,14].…”