CAREER: Tuning Complexity in Rare-Earth Transition Metal Oxides

职业：调整稀土过渡金属氧化物的复杂性

• 批准号: 2145174
• 负责人: Katharine Page
• 金额: $ 70.13万
• 依托单位: University of Tennessee Knoxville
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-04-01 至 2027-03-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2145174&HistoricalAwards=false
• 关键词: CAREER; Tuning; Complexity; Rare; Earth

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).NON-TECHNICAL SUMMARYMaterials called “complex oxides” are essential for technologies such as cell phone batteries, capacitors in all kinds of electronic devices, and catalysts that clean up industrial pollutants. These materials contain oxygen and two or more types of metal ions. This configuration allows for highly variable composition (which ions are present) and structure (how the ions are arranged), which can be harnessed to improve the technologies that rely on these families of compounds. With this CAREER award, Professor Katharine Page at the University of Tennessee Knoxville will study “High Entropy Oxides” (HEOs) that contain five or more ions of rare-earth elements or transition metals, which can provide an extremely vast array of compositions and structures. By using novel techniques to uncover and influence how the various HEO atoms interact, this research will reveal how to combine multiple desirable physical properties into a single material. These insights will lead to more efficient, more powerful, and more diverse fuel cells, catalysts, sensors, and electronics. Additionally, this project will produce a middle school workshop series that will promote careers in materials chemistry and related fields through hands-on activities that celebrate the creative exploration process of materials engineering and crystallography. Professors, graduate students, and undergrads involved in the research will teach and mentor participants in the workshop series at economically disadvantaged schools in rural East Tennessee and Appalachian communities.TECHNICAL SUMMARY With this CAREER award, Professor Katharine Page at the University of Tennessee Knoxville aims to uncover the rules for enabling hierarchical and tailored design in pyrochlore and layered perovskite-based rare earth transition metal complex oxide families featuring two to five atom types per lattice site. Relatively little is currently known about the classifications separating traditional complex oxide phases from the emerging class of High Entropy Oxides (materials involving five or more ions per lattice site), including the extent to which new design paradigms are needed to understand and control their physical properties. High entropy and kinetic reaction controls will be examined for their potential to produce single-phase materials and specific crystal-chemical conditions in the pyrochlore family, seeking to improve ionic conductivity at lower working temperature for potential applications in solid oxide fuel cells and catalysts. Similar approaches will seek to tune magnetic, electronic, and multiferroic responses in the layered perovskite family. Sophisticated scattering probes, theoretical tools, and multi-modal modeling methods will be combined to evaluate the impact of local to long-range structure traits on the electronic and magnetic properties of the respective series. The extent to which specific defects, distortions, and chemical short-range order may be achieved and tuned to impact the stability and respective properties of the structural classes will be determined. This fundamental materials chemistry approach will lead to the foundational insights necessary to design HEO materials with desired combinations of traits. Relationships governing the stability, local to global symmetry, and overall tunability in HEOs emerging from this work will impact the broader exploration of complex oxide chemistries unfolding across multiple disciplines and applications. Concurrently, this project will promote a new generation of scientists through outreach, teaching, and mentoring activities that celebrate the creative exploration process of materials chemistry and crystallography approaches as part of a workshop series for traditionally marginalized groups at economically disadvantaged middle schools in rural East Tennessee and Appalachian communities.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该奖项全部或部分由2021年美国救援计划法案（公法117-2）资助。非技术概述被称为“复合氧化物”的材料对于手机电池、各种电子设备中的电容器以及清理工业污染物的催化剂等技术至关重要。这些材料含有氧和两种或更多种类型的金属离子。这种配置允许高度可变的组成（存在哪些离子）和结构（离子如何排列），这可以用来改进依赖于这些化合物家族的技术。有了这个职业奖，田纳西大学诺克斯维尔的凯瑟琳·佩奇教授将研究“高熵氧化物”（HEO），它含有五个或更多的稀土元素或过渡金属离子，可以提供极其广泛的组成和结构。通过使用新技术来揭示和影响各种HEO原子如何相互作用，这项研究将揭示如何将联合收割机多种理想的物理特性结合到一种材料中。这些见解将导致更高效，更强大，更多样化的燃料电池，催化剂，传感器和电子产品。此外，该项目将产生一个中学研讨会系列，通过庆祝材料工程和晶体学的创造性探索过程的实践活动，促进材料化学和相关领域的职业生涯。参与研究的教授、研究生和本科生将在田纳西州东部农村和阿巴拉契亚社区的经济困难学校教授和指导研讨会系列的参与者。田纳西大学诺克斯维尔的凯瑟琳·佩奇教授旨在揭示烧绿石和层状钙钛矿中实现分层和定制设计的规则，基于稀土过渡金属复合氧化物族，其特征在于每个晶格位置具有2至5种原子类型。目前对将传统的复合氧化物相与新兴的高熵氧化物（每个晶格位置涉及五个或更多离子的材料）相分离的分类知之甚少，包括需要新的设计范例来理解和控制其物理性质的程度。将检查高熵和动力学反应控制是否有潜力产生烧绿石家族中的单相材料和特定的晶体化学条件，寻求在较低工作温度下提高离子电导率，以用于固体氧化物燃料电池和催化剂的潜在应用。类似的方法将寻求调整层状钙钛矿家族中的磁性，电子和多铁性响应。先进的散射探针，理论工具和多模态建模方法将结合起来，以评估本地到远程结构特征对相应系列的电子和磁性的影响。将确定特定缺陷、畸变和化学短程有序可实现和调整以影响结构类别的稳定性和相应性质的程度。这种基本的材料化学方法将导致设计具有所需特性组合的HEO材料所需的基本见解。从这项工作中出现的HEO的稳定性，局部到全局对称性和整体可调性的关系将影响复杂氧化物化学在多个学科和应用中展开的更广泛的探索。同时，该项目将通过外联、教学、和指导活动，庆祝材料化学和晶体学方法的创造性探索过程，作为田纳西州东部农村和阿巴拉契亚社区经济弱势中学传统边缘化群体研讨会系列的一部分。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估。

项目成果

Local cation order and ferrimagnetism in compositionally complex spinel ferrites

• DOI: 10.1063/5.0123728
• 发表时间: 2022-12
• 期刊: APL Materials
• 影响因子: 6.1
• 作者: Xin Wang;B. Musicó;C. Kons;Peter C. Metz;V. Keppens;D. Gilbert;Yuanpeng Zhang;K. Page

Phase Selectivity and Stability in Compositionally Complex Nano (nA1/n)Co2O4

• DOI: 10.1021/acs.chemmater.3c01647
• 发表时间: 2023-08
• 期刊: Chemistry of Materials
• 影响因子: 8.6
• 作者: Xin Wang;Peter C. Metz;E. Calì;P. R. Jothi;E. Lass;K. Page

Local cation ordering in compositionally complex Ruddlesden–Popper n = 1 oxides

• DOI: 10.1063/5.0144766
• 发表时间: 2023-05
• 期刊: APL Materials
• 影响因子: 6.1
• 作者: Bo Jiang;K. Pitike;D. Lin;Stephen C. Purdy;Xin Wang;Yafan Zhao;Yuanpeng Zhang;Peter C. Metz-

Entropy-driven phase transitions in complex ceramic oxides

• DOI: 10.1103/physrevmaterials.6.090301
• 发表时间: 2022-09
• 期刊: Physical Review Materials
• 影响因子: 3.4
• 作者: R. Spurling;E. Lass;Xin Wang;K. Page