The ceramics based on (Bi_0.5Li_0.5)_0.9Sr_0.1ZrO₃-doped K_0.44Na_0.55Ag_0.01Nb_0.95Ta_0.05O₃ exhibit enhanced structural and electric properties

Currently, in the modification methods of K_0.5Na_0.5NbO₃(KNN) ceramics to enhance their piezoelectric performance, key parameters such as Curie temperature are usually sacrificed. However, this trade-off limits the practical application of piezoelectric materials. Thus, addressing the trade-off between different performance parameters of piezoelectric ceramics becomes a major challenge.The present research employs the conventional solid phase sintering process and utilizes controlled doping of (Bi_0.5Li_0.5)_0.9Sr_0.1ZrO₃ to regulate the ceramic system, K_0.44Na_0.55Ag_0.01Nb_0.95Ta_0.05O₃, at its polycrystalline phase boundary, thereby achieving a trade-off between performance. The ceramic samples of the system formed a compact solid solution with a single-phase perovskite structure and formed orthorhombic-tetragonal and rhombohedral-tetragonal polycrystalline phase boundaries at 0.02 ≤ x ≤ 0.03 and 0.035 ≤ x ≤ 0.06, respectively, according to XRD, SEM, and EDS analysis. The electrical properties test results show that in the multiphase coexisting region of x = 0.035, the ceramics of the system show excellent electrical properties, respectively d₃₃ = 312 pC/N, k_p = 46.5%, ε_r = 1019, tanδ = 3.78%, P_r = 20.08 μC/cm², E_c = 12.97 kV/cm, and T_C = 342 ℃. These results show that the properties of the system ceramics have reached a relatively high level, which provides an effective strategy for the practical application of piezoelectric ceramics.