Effect of Magnesium Substitution on Dielectric Constant of Zn_2-xMg_xInV₃O₁₁ (x = 0.0, 0.4, 1.6) Solid Solutions

Abstract

The results of magnetic and dielectric measurements of Zn2−xMgxInV3O11 phases with x = 0.0, 0.4, and 1.6 showed diamagnetic behavior above room temperature and a strong increase in the relative electrical permittivity, εr, with an increase in the magnesium content as well as the high loss tangent, tan δ, above 150 K, irrespective of the magnesium content in the sample. With the increase in the frequency of the electric field both εr and tan δ strongly decreased. At low temperatures a residual paramagnetism coming from the paramagnetic ions of vanadium was observed. These effects were interpreted within a framework of the vacancy trapping centers acting as the accumulation of electric charges on the one hand and a mixed valence of vanadium ions on the other.

Electrical Properties of Yb2-xVxO3+x Nanomaterials Obtained Mechanochemically from Yb2O3 and V2O5 Oxides

“…Similar behavior with a wide maximum in the ε r (T ) and tan(δ)(T ) curves was found in Ca 1−x Mn x MoO 4 (0 ≤ x ≤ 0.15) nanomaterials [27]. For comparison, microcrystalline M 2 FeV 3 O 11 (M = Mg, Zn, Pb, Co, and Ni) [16] and MPr 2 W 2 O 10 (M = Co, Mn) [28] compounds containing 3d elements with the unpaired electrons as well as the semiconducting Zn 2−x Mg x InV 3 O 11 (0 ≤ x ≤ 2.0) micromaterials [18,19] showed both much higher ε r and tan(δ) than the nanomaterials under study and the Ca 1−x Mn x MoO 4 [27] ones mentioned above. This may mean that a small grain size hampers an electric charge accumulation in each sample.…”

“…Their electrical conductivity decreased with increasing ytterbium content, and the breakdown voltage oscillated around the value of 26 V/mm and was characteristic (or typical) of the varistor behavior [17]. Next, Zn 2−x Mg x InV 3 O 11 materials (where x = 0.0, 0.4, 1.0, 1.6, and 2.0) showed n-type semiconducting properties with activation energies of 0.147-0.52 eV in the temperature range of 250-400 K, symmetrical and linear I-V characteristics at both 300 K and 400 K, stronger carrier emission for the Zn 2 InV 3 O 11 matrix and much lower for the remaining samples, and dipole relaxation, which was slower for the sample with x = 0.0 (matrix) and faster for the Mg-doped samples with x > 0.0 [18,19].…”

Dipole Relaxation in Semiconducting Zn2−xMgxInV3O11 Materials (Where x = 0.0, 0.4, 1.0, 1.6, and 2.0)

“…Next, in the absorption band covering the range 900-400 cm −1 , the stretching vibrations were ascribed to the moderately distorted VO 4 tetrahedra or to stretching vibrations in ZnO x and MgO x [1,[13][14][15][16]. Recently, the preliminary results of magnetic and dielectric measurements of Zn 2−x Mg x InV 3 O 11 phases with x = 0.0, 0.4, and 1.6 showed diamagnetic behavior above room temperature and a strong increase in the relative electrical permittivity as the magnesium content increased [17].…”