Fabrication and physical properties of ferroelectrics confined in nanoporous materials

纳米多孔材料中铁电体的制备和物理性能

• 批准号: 5442187
• 负责人: Professor Dr. Jürgen Haase
• 金额: --
• 依托单位: V.A. Fock Institute of Physics
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2004
• 资助国家: 德国
• 起止时间: 2003-12-31 至 2008-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5442187?language=en
• 关键词: Fabrication; physical; properties; ferroelectrics; confined

Fabrication and studies of ferroelectric materials within nanoporous matrices (porous glasses, artificial opals, zeolites, mesoporous materials of type MCM-41, MCM-48 and SBA-15) with characteristic sizes in the range of 0.7 to 100 nm are planned. NaNO2, BaTiO3, and KDP nanostructures will be prepared. The main goal of the project consists in studying size effects on phase transitions in ferroelectric nanostructures (shifts of the phase transition temperatures, sizeinduced suppression of ferroelectric phase transitions, smearing the phase transitions) using NMR and acoustic methods. This allows to investigate changes in the microscopic parameters (local electric and magnetic field distribution, chemical bonding) and in the kinetics of the order parameter in confined ferroelectrics. The role of pore geometry (irregular three-dimensional pore network in porous glasses, regular pore lattices in artificial opals, zeolites and mesoporous materials, like MCM 41, will be investigated. The experimental results will be compared with theoretical predictions on the basis of a phenomenological treatment of ferroelectric phase transitions in small particles and thin films.

计划制造和研究特征尺寸在 0.7 至 100 nm 范围内的纳米多孔基质（多孔玻璃、人造蛋白石、沸石、MCM-41、MCM-48 和 SBA-15 型介孔材料）内的铁电材料。将制备NaNO2、BaTiO3 和KDP 纳米结构。该项目的主要目标包括使用核磁共振和声学方法研究铁电纳米结构中相变的尺寸效应（相变温度的变化、铁电相变的尺寸诱导抑制、相变模糊）。这允许研究微观参数（局部电场和磁场分布、化学键合）以及受限铁电体中有序参数动力学的变化。将研究孔隙几何形状（多孔玻璃中不规则三维孔隙网络、人造蛋白石、沸石和介孔材料（如 MCM 41）中规则孔隙晶格）的作用。实验结果将与理论预测进行比较小颗粒和薄膜中铁电相变的唯象处理。