Effect of Ferric Oxide Nanoparticles Incorporation on Structure and Electrical Properties of Modified BNKT Ceramics

The BNKBST30 + 3 vol% Fe2O3 ceramic was fabricated via a solid-state mixed oxide and sintered 1125°C for 2 h. The effects of ferric oxide nanoparticles (Fe2O3) additive on phase evolution, microstructure and electrical properties, i.e. dielectric, ferroelectric and electric field-induced strain, of BNKBST30 ceramic was investigated. The obtain ceramic was well sintered and densely with high density of 5.78 g/cm3. X-ray diffraction pattern and Raman spectra analysis showed a single perovskite with a mixed rhombohedral (R3c) and tetragonal (P4bm) phases. The obtained ceramic had a cubic-like grain shape with an average grain size of 0.82 µm. The dielectric constant as a function of temperature curves exhibited broad transition peaks at maximum temperature (Tm). The ceramic also showed good dielectric (er = 1085, tan d = 0.0496, er,max = 6099, Tm = 296 °C), ferroelectric (Pr = 27.18 µC/cm2, Ec = 20.32 kV/cm, Rsq = 0.95), and electric field-induced strain properties (Smax = 0.22 %, Sneg = - 0.08 %, d*33 = 440 pm/V). The obtained results indicated that the studied ceramic is considered as candidate for lead-free electromechanical applications.