Energy material Sm-modified lead zirconate titanate (PZT) ceramics: preparation, characterisation and application

Polycrystalline Lead zirconate titanate (PZT) ceramics is an excellent dielectric, piezoelectric and ferroelectric material that exhibits interesting electrical and electromechanical properties and has tremendous device applications in the form of sensor, actuator and transducer. With specific requirements, its physical properties can be modified with compositional fluctuations, suitable substitutions and proper physical conditions. The samples of Sm ³⁺-modified Lead zirconate titanate [PSZT; Pb_1-x Sm_x (Zr_0.60 Ti_0.40)_1.x/4 O₃; x = 0.00, 0.03, 0.06 and 0.09] ceramics have been prepared by the high temperature solid-state reaction technique. Preliminary structural analysis using X-ray diffraction technique confirms the formation of compounds in single phase tetragonal crystal system. Dielectric properties of the materials were analyzed within wide ranges of frequencies (1kHz-1MHz) and temperatures (30°C-500°C). Dielectric constant (#_r) of the materials are found to decrease with increase in frequency but exhibit an increasing trend with increase in temperature exhibiting ferroelectric-paraelectric phase transition at well above the room temperature. The tangent loss (Tan#) of the materials is found to be very low and its value remains low upto very high temperature close to the transition temperature. The temperature-frequency dependence of ac conductivity (#_ac) of the materials exhibits the presence of different type of charge species. It is observed that oxygen vacancy plays an important role for high temperature conduction mechanism and dynamics of polarization of the system. The piezoelectric coefficient (d₃₃) of the poled PSZT samples is found to be very high that enables the materials highly suitable for sensing and transducing purposes in research and industries.