Abstract

Linear and nonlinear dielectric properties of new organic ferroelectric diisopropylammonia iodide (DIPAI) introduced into porous aluminum oxide films have been studied in comparison with the properties of a bulk DIPAI. In DIPAI, in pores 300 and 60 nm in diameter, it has been found that the ferroelectric phase forms on heating and on cooling in the temperature range between two structural phase transitions above room temperature. No marked temperature hysteresis is observed for both the phase transitions. The boundaries of the intermediate polar phase in the nanostructured DIPAI is shown to shift to lower temperatures as the pore size decreases. For the bulk DIPAI, two structural transitions are observed on heating with the formation of an intermediate polar phase and only one transition below which the ferroelectricity forms is observed on cooling. This transition temperature is significantly lower than the corresponding temperature on heating. It is assumed that the observed differences of the phase transition in DIPAI in pores and in the bulk DIPAI are related to an acceleration of the kinetics of the phase transitions in the nanoconfinement conditions.

中文翻译：

---

纳米限制对有机铁电DIPAI中相变动力学的影响

摘要

与块状DIPAI的性能比较，研究了引入多孔氧化铝膜中的新型有机铁电二异丙基碘化碘碘化物（DIPAI）的线性和非线性介电性能。在DIPAI中，发现在直径300和60nm的孔中，铁电相在加热和冷却时在高于室温的两个结构相变之间的温度范围内形成。两个相变均未观察到明显的温度滞后。随着孔径的减小，纳米结构的DIPAI中的中间极性相的边界显示为转移到较低的温度。对于批量DIPAI，在加热过程中观察到两个结构转变，形成中间极性相，而在冷却过程中仅观察到一个低于其的铁电形成的转变。该转变温度明显低于加热时的相应温度。假设在孔中和在本体DIPAI中观察到的DIPAI中相变的差异与纳米约束条件下相变动力学的加速有关。