Bismuth titanate (Bi₄Ti₃O₁₂, BIT) piezoelectric materials have attracted increasing attention due to their high-temperature applications. However, it is quite challenging to simultaneously achieve outstanding piezoelectric properties and high Curie temperature in BIT-based systems. In this study, oxygen vacancy defects tailoring strategy was utilized to solve this problem, excellent piezoelectric coefficient (32.1 pC/N), and ultrahigh Curie temperature (659 °C) are gotten in Bi₄Ti_3-x(Mn_1/3Nb_2/3)_xO₁₂ (BTMN) ceramics, which are among the top values in the BIT-based ceramics. More importantly, the (Mn_1/3Nb_2/3)^(4+δ)+ complex-ion modified Bi₄Ti₃O₁₂-based ceramics are characterized with excellent piezoelectric stability up to 500 °C (d₃₃ > 30.0 pC/N at 500 °C)) and significantly reduced conductivity (only ∼ 10⁻⁷ Ω⁻¹ cm⁻¹ at 500 °C). Moreover, enhanced ferroelectricity and good dielectric stability were also obtained. The better comprehensive properties can be ascribed to two aspects. First, the concentration of oxygen vacancy defects is obviously reduced, and their distribution is effectively controlled in BITMN ceramics. Second, the introduction of (Mn_1/3Nb_2/3)^(4+δ)+ complex-ion gives rise to the antiphase boundaries and massive ferroelectric domain walls. This works not only reveal the high potential of BITMN ceramics for high-temperature piezoelectric applications but also deepen the understanding of the structure-properties relationship in BIT-based materials.

钛酸铋（Bi ₄ Ti ₃ O ₁₂，BIT）压电材料由于其高温应用而引起了越来越多的关注。然而，在基于BIT的系统中同时实现出色的压电性能和居里温度高是非常具有挑战性的。在这项研究中，采用了氧空位缺陷定制策略来解决此问题，在Bi ₄ Ti _3-x（Mn _1/3 Nb ）中获得了优异的压电系数（32.1 pC / N）和超高居里温度（659°C）。_2/3）_x O ₁₂（BTMN）陶瓷，在BIT基陶瓷中属于最高值。更重要的是，_1/3 Nb _2/3）^{（4 +δ）+}络合离子改性的Bi ₄ Ti ₃ O ₁₂基陶瓷的特点是在高达500°C的温度下具有出色的压电稳定性（d ₃₃  > 30.0 pC / N在500°C时） ）），并减小显著电导率（仅〜10 ^-7  Ω ^-1 厘米^-1，在500℃）。此外，还获得增强的铁电性和良好的介电稳定性。更好的综合性能可以归结为两个方面。首先，氧空位缺陷的浓度明显降低，并且在BITMN陶瓷中其分布得到有效控制。二，引入（Mn _1/3Nb _2/3）^{（4 +δ）+}络合离子产生反相边界和大量铁电畴壁。这项工作不仅揭示了BITMN陶瓷在高温压电应用中的巨大潜力，而且加深了对基于BIT的材料中结构与性能关系的理解。