Abstract Porous tetragonal PbTiO3 nanowires, synthesized through an intermediate pre-perovskite structure, exhibit distinct behaviors from those of the corresponding bulk PbTiO3. Here we investigate the role of nanopores in the ferroelectric, dielectric, and piezoelectric properties of ferroelectric PbTiO3 nanowires employing phase-field simulations. It is found that the presence of pores gives rise to large enhancements in both dielectric constant and piezoelectric coefficient by ~50% and 30%, respectively, compared with those of the bulk PbTiO3. It is shown that the smaller the pore size is, the higher the dielectric and piezoelectric responses of the nanowire are. A charge compensation mechanism is proposed to explain the experimentally measured change of oxygen ions concentration at the pore surfaces. The findings provide in-depth insights into modulation of material properties through nanopores.

中文翻译：

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PbTiO3纳米线中纳米孔诱导的介电和压电增强

摘要 通过中间钙钛矿结构合成的多孔四方 PbTiO3 纳米线表现出与相应块状 PbTiO3 不同的行为。在这里，我们使用相场模拟研究了纳米孔在铁电 PbTiO3 纳米线的铁电、介电和压电特性中的作用。结果表明，与大块 PbTiO3 相比，孔隙的存在使介电常数和压电系数分别提高了约 50% 和 30%。结果表明，孔径越小，纳米线的介电和压电响应越高。提出了一种电荷补偿机制来解释实验测量的孔隙表面氧离子浓度的变化。