Practical High Piezoelectricity in Barium Titanate Ceramics Utilizing Multiphase Convergence with Broad Structural Flexibility
Practical High Piezoelectricity in Barium Titanate Ceramics Utilizing Multiphase Convergence with Broad Structural Flexibility
复制标题
利用多相收敛和广泛的结构灵活性实现钛酸钡陶瓷的实用高压电性
DOI：
10.1021/jacs.8b07844
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发表时间：
2018
影响因子：
15
通讯作者：
Pennycook Stephen J.
中科院分区：
文献类型：
--
作者：
Zhao Chunlin;Wu Haijun;Li Fei;Cai Yongqing;Zhang Yang;Song Dongsheng;Wu Jiagang;Lyu Xiang;Yin Jie;Xiao Dingquan;Zhu Jianguo;Pennycook Stephen J.
由于对铅基压电材料毒性的环境关注日益增加，迫切需要无铅替代品，但迄今为止尚未能够达到具有竞争力的性能。在这里，我们采用了一种新的相边界工程策略，利用多相收敛，这导致了广泛的结构灵活性，在一个广泛的相边界区与连续的多态相变。我们在BaTiO 3基陶瓷中实现了700 ± 30 pC/N的压电常数（d33），在很宽的组成范围内保持>600 pC/N。通过Z衬度成像的原子分辨率极化映射揭示了三个铁电相（T + O + R）在纳米尺度上共存，它们之间具有纳米尺度的极化旋转。理论模拟证实，大大降低了促进偏振旋转的能量障碍。我们的无铅材料在10-40 °C的温度范围内超过了大多数铅基系统（包括基准PZT-5 H）的性能，使其适合作为实际应用中的无铅替代品。本工作为设计具有上级机电性能的无铅功能材料提供了一种新的范例。
Due to growing environmental concerns on the toxicity of lead-based piezoelectric materials, lead-free alternatives are urgently required but so far have not been able to reach competitive performance. Here we employ a novel phase-boundary engineering strategy utilizing the multiphase convergence, which induces a broad structural flexibility in a wide phase-boundary zone with contiguous polymorphic phase transitions. We achieve an ultrahigh piezoelectric constant (d33) of 700 ± 30 pC/N in BaTiO3-based ceramics, maintaining >600 pC/N over a wide composition range. Atomic resolution polarization mapping by Z-contrast imaging reveals the coexistence of three ferroelectric phases (T + O + R) at the nanoscale with nanoscale polarization rotation between them. Theoretical simulations confirm greatly reduced energy barriers facilitating polarization rotation. Our lead-free material exceeds the performance of the majority of lead-based systems (including the benchmark PZT-5H) in the temperature range of 10–40 °C, making it suitable as a lead-free replacement in practical applications. This work offers a new paradigm for designing lead-free functional materials with superior electromechanical properties.