The difference between the oxides-hydrothermal (O-HT) method and the traditional hydrothermal method is that the former uses insoluble or poorly soluble metal oxides as raw materials. The O-HT method is mainly used to study the luminescence properties of rare-earth nanomaterials. In this work, the O-HT method has been used for the synthesis of high-Curie temperature (high-T_C) 0.3Bi(Ni_1/2Ti_1/2)O₃–0.7Pb(Zr_0.52Ti_0.48)O₃ (0.3BNT–0.7PZT) piezoelectric ceramic powders at different hydrothermal synthesis temperatures. After the O-HT synthesis, ceramic powders are calcined and sintered. The effects of different hydrothermal synthesis temperatures on the crystallinity, structure, morphology, and electrical performance of the products are investigated. At a low hydrothermal synthesis temperature of 200 °C for 12 h, well-crystallized ceramic powders are obtained. After sintering, the ceramic samples exhibit a dense microstructure and optimal electrical properties (ε_r = 6840, d₃₃ = 501 pC/N, T_C = 245 °C, P_r = 14.79 μC/cm², and E_c = 16.86 kV/cm). The experimental results show that applying O-HT technology can dramatically induce grain growth during sintering and improve the piezoelectricity and Curie temperature of samples and that it has the advantages of energy saving, environmental recycling, and suitability for industrial mass production.

中文翻译：

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通过氧化物-水热法增强高居里温度 BNT-PZT 压电陶瓷的电性能

氧化物水热法（O-HT）与传统水热法的区别在于，前者以不溶性或难溶性金属氧化物为原料。O-HT法主要用于研究稀土纳米材料的发光特性。在这项工作中，O-HT 方法已用于合成高居里温度 (high- T _C ) 0.3Bi(Ni _1/2 Ti _1/2 )O ₃ –0.7Pb(Zr _0.52 Ti _0.48 )O ₃(0.3BNT–0.7PZT) 不同水热合成温度下的压电陶瓷粉末。O-HT合成后，陶瓷粉末被煅烧和烧结。研究了不同水热合成温度对产物结晶度、结构、形貌和电性能的影响。在 200°C 的低水热合成温度下 12 小时，获得结晶良好的陶瓷粉末。烧结后，陶瓷样品表现出致密的微观结构和最佳电性能（ε _r = 6840，d ₃₃ = 501 pC/N，T _C = 245 °C，P _r = 14.79 μ C/cm ²和E _c= 16.86 kV/cm)。实验结果表明，应用O-HT技术可以显着诱导烧结过程中晶粒长大，提高样品的压电性和居里温度，具有节能、环境回收、适合工业化批量生产等优点。