Relaxor-ferroelectric BaLnZT (Ln=La, Nd, Sm, Eu, and Sc) ceramics for actuator and energy storage application

Lead free ceramics Ba_1-xLn_2x/3Zr_0.3Ti_0.7O₃ (Ln=La, Nd, Sm, Eu and Sc), x=0.02-0.10 are investigated for electrostrictive effect and energy storage properties in the proximity of relaxor-paraelectric phase boundary. Relaxor phase evidence from slim hysteresis loop and low remnant polarization are the key parameters responsible for improve the electrostrictive effect and energy storage properties simultaneously. With increase in rare earth content negative strain disappeared and almost hysteresis free strain is achieved. Strain-hysteresis profile in term of S-E, S-E ² and S-P ² is used to analyze the electrostrictive behavior of these ceramics. An average strain (S%) ∼ 0.03%, is accomplished at initial concentrations of x=0.02-0.04 and electrostrictive coefficients (Q ₁₁, and M ₁₁) as well as the energy storage density is improved by a factor of 1.2 and 2.6 respectively when compare with pure (x=0.0) ceramic. Above x ≥ 0.06, all compositions show a stable behavior which suggested the possibilities of these relaxor ceramics towards high precision actuators and energy storage application.