CAREER: SusChEM: Dynamic Defect Interactions in Ferroelectrics

职业：SusChEM：铁电体中的动态缺陷相互作用

• 批准号: 1555015
• 负责人: Geoff Brennecka
• 金额: $ 45.8万
• 依托单位: Colorado School of Mines
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-06-01 至 2022-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1555015&HistoricalAwards=false
• 关键词: CAREER; SusChEM; Dynamic; Defect; Interactions

NON-TECHNICAL DESCRIPTION: All ceramics contain defects, impurities, and interfaces; this is simply unavoidable. Decades of work have gone into understanding the effects of defects on properties, but the vast majority of this prior work has focused on static or steady-state conditions. Ferroelectrics (materials with a permanent dipole that can be reoriented by an electric field) and piezoelectrics (materials that develop an electric charge when a mechanical stress is applied) are important for applications ranging from memory devices and capacitors that help cram more features into smaller electronic devices to actuators that increase automotive fuel economy and devices that harvest ambient vibrational energy. These types of materials are commonly used under dynamic conditions in which moving domain walls dominate the property responses. This project uses new experimental techniques and unique sample sets to improve the quantitative descriptions of the interactions of these moving domain walls with ubiquitous point defects and interfaces such as vacancies and grain boundaries. Better understanding of domain wall interactions with defects and interfaces enables improved performance from Pb-free piezoelectrics and active control of high-value catalysts which are free of toxic or precious metals, thus using more sustainable materials to produce devices that contribute to increased energy efficiency and process sustainability across a variety of industries. The project integrates with the PI?s extensive efforts to expand student engagement including participation in an annual Discover STEM! Camp, curriculum development, and introduction of a hot glass shop on campus. A student swap agreement allows the supported graduate student to work for several weeks each year with collaborators in Virginia and Australia, taking advantage of the tools and expertise available in those groups while benefitting from the experience of living and working in a different environment.TECHNICAL DETAILS: This work links the abstract energy barriers currently used to describe the domain nucleation and pinning processes to real chemical and/or structural features in order to identify and generalize the conditions under which various features serve as nucleation and/or pinning sites. The sample sets and experiments isolate variables (e.g., domain wall interactions with cation vacancies and with grain boundaries separately) and apply new tools including atom probe and X-ray tomographies, time domain thermal reflectance, and a custom low-impedance drive circuit to develop fundamental mechanistic descriptions of domain nucleation and pinning that will apply broadly across many materials families.

非技术描述：所有陶瓷都含有缺陷、杂质和界面;这是不可避免的。几十年来，人们一直在研究缺陷对性能的影响，但绝大多数先前的工作都集中在静态或稳态条件下。铁电体（具有永久偶极子的材料，可以通过电场重新定向）和压电体（当施加机械应力时产生电荷的材料）对于从存储器设备和电容器（有助于将更多功能塞进更小的电子设备）到提高汽车燃油经济性的致动器和收集环境振动能量的设备等应用都很重要。这些类型的材料通常在动态条件下使用，其中移动畴壁主导属性响应。该项目使用新的实验技术和独特的样品集，以改善这些移动畴壁与无处不在的点缺陷和界面，如空位和晶界的相互作用的定量描述。更好地了解畴壁与缺陷和界面的相互作用，可以提高无铅压电材料的性能，并对不含有毒或贵金属的高价值催化剂进行主动控制，从而使用更可持续的材料来生产有助于提高能源效率和各种行业工艺可持续性的设备。该项目与PI整合？的广泛努力，以扩大学生的参与，包括在年度发现干参与！营地，课程开发，并在校园内推出热玻璃店。学生交换协议允许受资助的研究生每年与弗吉尼亚州和澳大利亚的合作者一起工作几周，利用这些团体提供的工具和专业知识，同时受益于在不同环境中生活和工作的经验。这项工作将目前用于描述畴成核和钉扎过程的抽象能垒与真实的化学和/或物理过程联系起来。或结构特征，以便识别和概括各种特征用作成核和/或钉扎位置的条件。样本集和实验隔离变量（例如，磁畴壁与阳离子空位和晶界的相互作用），并应用新的工具，包括原子探针和X射线断层扫描，时域热反射，和一个定制的低阻抗驱动电路，以开发磁畴成核和钉扎的基本机制描述，将广泛应用于许多材料家族。

项目成果

Thin film growth effects on electrical conductivity in entropy stabilized oxides

• DOI: 10.1016/j.jeurceramsoc.2020.12.021
• 发表时间: 2020-06
• 期刊: arXiv: Materials Science
• 作者: V. Jacobson;D. Diercks;B. To;A. Zakutayev;G. Brennecka

Combined electromechanical dynamic fracture behavior of lead zirconate titanate (PZT)

锆钛酸铅（PZT）的复合机电动态断裂行为

• DOI: 10.1111/jace.18279
• 发表时间: 2022
• 期刊: Journal of the American Ceramic Society
• 影响因子: 3.9
• 作者: Mendoza, Isabella;Drury, Daniel;Koumlis, Stylianos;Ivy, Jacob;Brennecka, Geoff;Lamberson, Leslie
• 通讯作者: Lamberson, Leslie

Lithium diffusion in lithium tantalate as measured by confocal Raman spectroscopy

• DOI: 10.1007/s10853-022-07105-y
• 发表时间: 2022-03
• 期刊: Journal of Materials Science
• 影响因子: 4.5
• 作者: Jacob Ivy;G. Brennecka

The role of Co valence in charge transport in the entropy‐stabilized oxide (Mg 0.2 Co 0.2 Ni 0.2 Cu 0.2 Zn 0.2 )O

Co 价态在熵稳定氧化物 (Mg 0.2 Co 0.2 Ni 0.2 Cu 0.2 Zn 0.2 )O 中电荷传输中的作用

• DOI: 10.1111/jace.18820
• 发表时间: 2022
• 期刊: Journal of the American Ceramic Society
• 影响因子: 3.9
• 作者: Jacobson, V.;Huang, J.;Titus, C. J.;Smaha, R. W.;Papac, M.;Lee, S. J.;Zakutayev, A.;Brennecka, G. L.
• 通讯作者: Brennecka, G. L.

Synthesis and Surface Chemistry of 2D TiVC Solid-Solution MXenes

• DOI: 10.1021/acsami.0c03181
• 发表时间: 2020-04-29
• 期刊: ACS APPLIED MATERIALS & INTERFACES
• 影响因子: 9.5
• 作者: Yazdanparast, Sanaz;Soltanmohammad, Sina;Brennecka, Geoff L.
• 通讯作者: Brennecka, Geoff L.