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。为了理解缺陷对性能的影响，人们已经进行了数十年的工作，但之前的绝大多数工作都集中在静态或稳态条件上。铁电体（具有可通过电场重新定向的永久偶极子的材料）和压电体（在施加机械应力时产生电荷的材料）对于存储设备和电容器等应用非常重要，这些应用有助于将更多功能塞进更小的电子设备中。提高汽车燃油经济性的执行器设备以及收集环境振动能量的设备。这些类型的材料通常在动态条件下使用，其中移动的畴壁主导性能响应。该项目使用新的实验技术和独特的样本集来改进这些移动畴壁与普遍存在的点缺陷和界面（例如空位和晶界）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，并主动控制不含有毒或贵金属的高价值催化剂，从而使用更可持续的材料来生产有助于提高能源效率和性能的设备。跨多个行业的流程可持续性。该项目与 PI 为扩大学生参与度所做的广泛努力相结合，包括参与一年一度的 Discover STEM！营地、课程开发以及在校园内开设热玻璃店。学生交换协议允许受支持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。技术细节：这项工作将目前用于描述域成核和钉扎过程的抽象能量势垒与真实的化学和/或结构特征联系起来，以便识别和概括各种特征作为成核和/或钉扎位点的条件。样本集和实验隔离变量（例如，分别与阳离子空位和晶界的畴壁相互作用），并应用包括原子探针和 X 射线断层扫描、时域热反射和定制低阻抗驱动电路在内的新工具来开发域成核和钉扎的基本机制描述，将广泛应用于许多材料系列。

项目成果

Lithium diffusion in lithium tantalate as measured by confocal Raman spectroscopy

通过共焦拉曼光谱测量钽酸锂中的锂扩散

• DOI: 10.1007/s10853-022-07105-y
• 发表时间: 2022-03-28
• 期刊: Journal of Materials Science
• 影响因子: 4.5
• 作者: Jacob Ivy;G. Brennecka
• 通讯作者: 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: 2022-10
• 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.

Density-functional theory calculation of magnetic properties of BiFeO 3 and BiCrO 3 under epitaxial strain

外延应变下BiFeO 3 和BiCrO 3 磁性能的密度泛函理论计算

• DOI: 10.1063/5.0054979
• 发表时间: 2021-09
• 期刊: Journal of Applied Physics
• 影响因子: 3.2
• 作者: Walden, Michael R.;Ciobanu, Cristian V.;Brennecka, Geoff L.
• 通讯作者: Brennecka, Geoff L.

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: 2022-01
• 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

Thin film growth effects on electrical conductivity in entropy stabilized oxides

薄膜生长对熵稳定氧化物电导率的影响

• DOI: 10.1016/j.jeurceramsoc.2020.12.021
• 发表时间: 2020-12
• 期刊: Journal of the European Ceramic Society
• 影响因子: 5.7
• 作者: Jacobson, V.;Diercks, D.;To, B.;Zakutayev, A.;Brennecka, G.
• 通讯作者: Brennecka, G.