Dielectric relaxation and electrical properties of Bi _2.5 Nd _0.5 Nb _1.5 Fe _0.5 O ₉ ceramics

Aurivillius single-phase Bi _2.5 Nd _0.5 Nb _1.5 Fe _0.5 O ₉ (BNNF) ceramics was synthesized via solid state mixed oxide sintering method. Electrical properties of the samples were intensely studied in a wide range of temperature (25 °C–650 °C). Dielectric behaviors were investigated by dielectric and impedance spectroscopies in the range (40 Hz−10 MHz) of frequency. Single dielectric relaxation was observed due to the grains contribution. The phase transition temperature (T _C ) was noticed at ∼270 °C. Kinetic analysis of dielectric data was used to understand the possible relaxation-conduction behaviors in the ceramics. Above ∼250 °C, relaxation and conduction of the ceramics was assigned to the motion of ionized oxygen vacancies. The Aurivillius ceramics has promising industrial applications in dielectric capacitors and piezoelectric transducers due to low leakage below ∼200 °C. The results could be valuable for designing and/or modifying properties of BNNF related materials.