SYNTHESIS AND CHARACTERIZATION OF Bi3Mg2Nb3O14 PYROCHLORE SYSTEM

Abstract

Synthesis of Bi₃Mg₂Nb₃O₁₄ pyrochlore was carried out using conventional solid-state method. Phase formation and electrical properties of Bi₃Mg₂Nb₃O₁₄ pyrochlore was investigated by employment of different spectroscopy techniques. The phase purity and formation mechanism were confirmed by X-ray diffraction analysis. The “ideal” Bi₃Mg₂Nb₃O₁₄ was formed at 1025 °C as cubic pyrochlore with minute traces of Mg₄Nb₂O₉ and MgNb₂O₆ phases. The determined grain size by SEM analysis was found in the range of 1.5 - 6.5 µm. Impedance spectroscopy study revealed that Bi₃Mg₂Nb₃O₁₄ pyrochlore was highly resistive with high activation energy of 1.36 eV. The recorded dielectric constant, ε’, was ~110; dielectric loss, tan δ, 10-3, both at room temperature and at frequency 1 MHz. No sign of ionic conduction was discerned and the mechanism was probably attributed to hopping-type.