Dielectric and piezoelectric properties of Sm3+ doped lead barium niobate (PBN) ceramics

Highlights: • XRD analysis revealed pure and Sm³⁺ lead barium niobate ceramic materials are single phase with rhombohedral(hexagonal) symmetry. • Broad dielectric peak phase transitions observed with temperature in pure and Re³⁺ ions. • The mechanical quality factor (Q_m) values have been found to increase with increase of Sm³⁺ content. -- Abstract: Rhombohedral samarium doped Lead based ceramic materials were fabricated by a high temperature conventional solid state mixed oxide ceramic process. The ceramic composition Pb_1-x-3y/2Ba_x ${\mathrm{Re}}_y^{3+}$ Nb₂O₆ (x = 0.35 and y = 0.00, 0.02, 0.04 and 0.06, Re³⁺ = Sm³⁺). The pure and Sm³⁺ doped lead barium niobate ceramic materials are single phase with rhombohedral(hexagonal) symmetry obtained from powder x-ray diffraction (XRD). The grain size has been measured for all the compositions and lying between 1.60 and 2.90 μm. Broad dielectric peak phase transitions observed with temperature in pure and Sm³⁺ ion modified lead barium niobate ceramic materials. It is observed that the high values of piezoelectric charge coefficients in d₃₁ and d₃₃ in Sm³⁺ doped lead barium niobate ceramics. The mechanical quality factor Q_m and d₃₃ increases with increase of Sm³⁺ ion concentration and indicating a highly polarisable lead ion contributing to high Curie temperature dielectric constant.