Ultra-low hysteresis electrostrictive strain with high thermal stability in Bi(Li0.5Nb0.5)O3-modified BaTiO3 lead-free ferroelectrics

Electric-field-induced strain is often generated in piezoceramics, in which domain wall motion inherently results in hysteresis and energy dissipation, and subsequently affects the design and performance of actuators. Here, we proposed a strategy to search for electric-field-induced strain with low hysteresis and high thermal stability in electrostrictive materials based on thermal stability consistency between strain S3 and dielectric constant εr. According to this strategy, we reported an ultra-low hysteresis (<10%) S3 with high thermal stability (ΔS/S30≤25%, S30 means the maximum strain Smax measured at 30 °C) and high electrostrictive coefficient Q33 (∼0.037-0.049 m4/C2) in Bi(Li0.5Nb0.5)O3-modified BaTiO3 (BT-xBLN) lead-free ferroelectrics with x = 0.08 from 30 °C to 120 °C, due to the high thermal stability of εr. This work would not only report an important candidate for applications in high-precision actuators, but also supply a novel strategy for electrostrictive materials to increase the strain level with high thermal stability.