Perovskite solid solutions of SrTi(Cu_1/3Nb_2/3)O₃ (STCN) modified 0.8Bi_0.5Na_0.5TiO₃−0.2Bi_0.5K_0.5TiO₃ (BNT-BKT) in the vicinity of morphotropic phase boundary composition were prepared. The dielectric and impedance properties associated with their structural evolution were investigated. Strong unsteadiness and large hysteresis (dielectric loss) under elevated temperature and variational frequency restrict the development of BNT-BKT based ceramics. Here we show a distinct phase transition from ferroelectric to ergodic relaxor phase that occurs with increasing STCN. Incremental chemical defects resulted from the substitution of the A/B site facilitate the distributions of polar nanoregions. The flatter and smoother dielectric curves between T _s and T _m illustrate good temperature stability. The complex impedance spectrums demonstrate that the compositions possess a mixed electronic and ionic conduction mechanism. More oxygen vacancies can be introduced into the lattice, contributing to a decremental impedance as the increased dopant. Meanwhile, will suppress p-type conduction and reduce dielectric loss. Favorable stabilities of dielectric permittivity, energy storage, and electrostrictive strain were achieved, attributed to the existence of nanodomains.

SrTi(Cu _1/3 Nb _2/3 )O ₃ (STCN) 改性的钙钛矿固溶体0.8Bi _0.5 Na _0.5 TiO ₃ -0.2Bi _0.5 K _0.5 TiO ₃(BNT-BKT)在同型相界附近制备了组成。研究了与其结构演变相关的介电和阻抗特性。BNT-BKT基陶瓷在高温变频下的强不稳定性和大滞后（介电损耗）限制了其发展。在这里，我们展示了随着 STCN 增加而发生的从铁电体到遍历弛豫相的明显相变。由 A/B 位点取代导致的化学缺陷增加，促进了极性纳米区域的分布。T _s和T _m之间更平坦和更平滑的介电曲线说明良好的温度稳定性。复阻抗谱表明该组合物具有混合的电子和离子传导机制。更多的氧空位可以引入晶格中，随着掺杂剂的增加，阻抗降低。同时，会抑制p型传导，降低介电损耗。由于纳米域的存在，实现了介电常数、能量存储和电致伸缩应变的良好稳定性。