Dielectric properties and microstructural characterization of cubic pyrochlored bismuth magnesium niobates

Effect of oxygen pressure on preferential orientation, microstructure and functional properties of Bi1.5MgNb1.5O7 thin films prepared by pulsed laser deposition

“…The dielectric constant varied from 50 to 106 whereas the dielectric loss tangent varied from 0.0033 to 0.0063. The dielectric constant is lower than the well-sintered BMN ceramic [30]. The dielectric constant is higher and the loss tangent is lower for BMN films grown at oxygen pressure of 10 Pa, when compared with samples grown at different pressure values.…”

Disordered Structures and Dielectric Properties of Ni-Doped Bismuth Magnesium Niobate Pyrochlores

“…The scanned ceramics show dense microstructure, and small grains are distributed at the grain boundaries of large grains in Figure 3 The ideal cubic pyrochlore structure forbids the appearance of {220} and {200} reflections due to the symmetry constraints. 10 It reveals that A-site and O′ atoms are displaced to lower…”

“…There are six Raman (R) activation modes, A 1g , E g , and 4F 2g involving only the movement of oxygen atoms among the 26 normal modes. 10 Figure 5 shows the Raman spectra and locally magnified mode profiles of Ni-BMN pyrochlores. It is noticed that more than six Raman modes are observed in the samples as shown in Figure 5(a).…”

Structures, phase transformations, and dielectric properties of (1−x)Bi2Zn2/3Nb4/3O7–xBi1.5NiNb1.5O7 pyrochlore ceramics prepared by aqueous sol–gel method

“…Members [17][18][19]. The crystal structure of the a-BZN, BNN and BMN pyrochlores are cubic structure with space group Fd3m, while it shows to adopt an orthorhombic distorted pyrochlore structure in the b-BZN ceramic [17,19].…”