BaTiO₃ (BT)-based piezoceramics with large temperature-stable strains and low hysteresis are urgently needed for high-precision actuators because of increasing environmental problems. Here, tetragonal [001]_c-textured (Ba_0.98Ca_0.02)(Ti_0.96Sn_0.04)O₃ (BCTS) ceramics with a texture degree (F₀₀₁) of ~98% were obtained via the templated grain growth (TGG) method. A large maximum unipolar strain (S_max) of ~0.24% with a low strain hysteresis (H_s) of ~3.8% and an optimized piezoelectric strain coefficient (d₃₃*) of ~1124 pm·V⁻¹ are simultaneously achieved in the textured BCTS ceramics. Moreover, the variation in the strain response is less than 20% from room temperature (RT) to 100 °C for the textured ceramics. The underlying mechanism for the optimized strain performance could be attributed to the synergetic effect of the polarization extension and a fine domain structure. This work provides new insight for achieving a balance of multiple strain properties (large strain, low hysteresis, and high-temperature stability) in BT-based ceramics, showing the widespread application prospects of lead-free ceramics in high-precision actuators.

In this paper, Sm-doped 0.96(K_0.48Na_0.52)(Nb_0.95Sb_0.05)–0.04Bi_0.5(Na_0.82K_0.18)_0.5ZrO₃ (abbreviated as KNSN–0.04BNKZ) lead-free piezoelectric ceramics were prepared by conventional solid-state sintering method and the effects of Sm₂O₃ on the phase structure, microstructure, electrical and luminescent properties of KNSN–0.04BNKZ potteries were studied. Results revealed that a single solid solution phase with pseudo-cubic perovskite structure was formed between KNSN–0.04BNKZ and Sm₂O₃. Existence of weak dielectric/ferroelectric properties with a diffuse dielectric anomaly and slim P–E hysteresis loops of the Sm-doped KNSN–0.04BNKZ demonstrated the ferroelectric relaxor behavior of the KNNS–0.04BNKZ–xSm ceramics. Accordingly, the temperature stability and fatigue behavior of the modified ceramics were significantly improved. It was found that the KNSN–0.04BNKZ ceramics with 0.002 mol Sm addition exhibited nearly temperature independent properties and fatigue-free behavior. Moreover, Sm-modified KNSN–0.04BNKZ exhibits a bright photoluminescence with a strong orange emission under visible light irradiation. As a material with both electrical and luminescent properties, it has good application prospect in future optoelectronic components by integrating its luminescent and electrical properties.