CAREER: Ionic and Thermal Transport Properties of Complex Oxides from First Principles

非技术相加和热输运现象在化学、生物和物理科学中普遍存在。例如，热或离子的运动对许多重要技术的效率、寿命和成本起着至关重要的作用，如大功率电子产品、电池和喷气发动机。然而，尽管这些过程对许多技术都很重要，但理解材料的离子和热传输性质如何取决于它们的原子排列方式是非常具有挑战性的。这阻碍了我们对现有材料性能的了解，并阻碍了具有增强性能的新材料的设计。该职业奖支持旨在使用计算机来预测和理解材料的离子和热传输特性的理论和计算研究和教育。特别是，PI将阐明决定离子在材料中移动速度的原子尺度因素。这一知识对于设计更高效的能源设备至关重要，因为电池和燃料电池提供的功率在很大程度上取决于离子插入电极和从电极中提取并通过电解液传输的速度。研究小组还将专注于材料的晶体结构与其热传输能力之间的联系。材料的热性能在许多应用中都很重要，包括微电子(需要尽可能有效地传递热量)和热障涂层，它们可以保护燃气轮机发动机的结构部件免受过热的影响。PI将使用对称原理、简单的晶体化学模型和大规模量子力学计算的组合来发展基本理解，从而允许设计具有定制热性能的新材料。这一职业奖的教育部分有两个目标。第一是通过颠覆与科学家及其工作有关的普遍刻板印象，让公众参与进来，促进更具包容性的科学形象。为了实现这一目标，国际和平协会将在奥斯汀进行公开宣传，突出公众可能不太了解的科学家的故事和贡献。这种直接的公众宣传应该使PI能够以一种比通常在电视或电影中遇到的更吸引人和更现实的方式来描绘科学家的工作。第二个教育目标是开发一套计算练习，以更有效的方式向工科本科生讲授关键的材料科学概念。随着工程和制造企业在产品开发的许多领域越来越依赖计算方法，计算技能对于进入劳动力市场的工程学毕业生来说至关重要。通过与材料信息学和本科教育专家的密切合作，PI将把计算材料和材料信息学研究与这一教育倡议结合起来，使工程学学生掌握在现代工程劳动力中取得成功所需的技能。技术总结这个职业奖项支持理论和计算研究，这些研究将揭开复合氧化物材料家族中离子和热传输的微观机制。PI将使用对称原理、简单的晶体化学模型和第一原理计算的组合来揭示基本知识，这些基础知识将促进具有定制传输特性的材料的合理设计。第一原理技术对于发现新的想法和对材料的离子和热传输性质的洞察至关重要，因为机械细节通常不能仅从实验中获得。这项研究计划将解决与复合氧化物的离子和热传输性质有关的几个公开问题。这包括(I)维度和原子无序对层状氧化物中离子输运的影响，(Ii)特殊结构扭曲和离子输运之间的强耦合，以及通过外延应变控制氧化物薄膜中的这些扭曲(从而控制这些输运性质)，(Iii)电子-晶格相互作用在降低(晶格)热导率中的作用，以及(Iv)在某些铁电氧化物中观察到的异常低热导率的根源。这一职业奖项的教育部分有两个目标。第一是通过颠覆与科学家及其工作有关的普遍刻板印象，让公众参与进来，促进更具包容性的科学形象。为了实现这一目标，国际和平协会将在奥斯汀进行公开宣传，突出公众可能不太了解的科学家的故事和贡献。这种直接的公众宣传应该使PI能够以一种比通常在电视或电影中遇到的更吸引人和更现实的方式来描绘科学家的工作。第二个教育目标是开发一套计算练习，以更有效的方式向工科本科生讲授关键的材料科学概念。随着工程和制造企业在产品开发的许多领域越来越依赖计算方法，计算技能对于进入劳动力市场的工程学毕业生来说至关重要。通过与材料信息学和本科教育专家的密切合作，PI将把计算材料和材料信息学研究与这一教育倡议结合起来，使工程学学生掌握在现代工程劳动力中取得成功所需的技能。

NON-TECHNICAL SUMMARYIonic and thermal transport phenomena are ubiquitous in the chemical, biological and physical sciences. For example, the movement of heat or ions plays a crucial role in the efficiency, lifetime, and cost of many important technologies, such as high-power electronics, batteries, and jet engines. However, despite the importance of these processes to many technologies, understanding how the ionic and thermal transport properties of materials depend on the way their atoms are arranged is very challenging. This impedes our understanding of the properties of existing materials and hinders the design of new materials with enhanced properties. This CAREER award supports theoretical and computational research and education that aims to use computers to predict and understand the ionic and thermal transport properties of materials. In particular, the PI will elucidate the atomic-scale factors that determine how quickly ions can move through materials. This knowledge is critical to the design of more efficient energy devices, since the power delivered by batteries and fuel cells is largely determined by the rate at which ions can be inserted and extracted from the electrodes and transported through the electrolyte. The research team will also focus on the connection between a material's crystal structure and its ability to transport heat. Thermal properties of materials are important in many applications, including e.g. microelectronics (where heat needs to be transported away as efficiently as possible) and thermal barrier coatings, which protect the structural components of gas-turbine engines from excessive heat. The PI will use a combination of symmetry principles, simple crystal chemical models and large-scale quantum mechanical computations to develop the fundamental understanding that would allow the design of new materials with tailored thermal properties.The educational component of this CAREER award has two goals. The first is to engage the general public and promote a more inclusive image of science by upending the popular stereotypes associated with scientists and their work. To achieve this goal, the PI will conduct public outreach in Austin highlighting stories and contributions of scientists that may be less well known to the general public. Such direct public outreach should allow the PI to portray the work of scientists in a way that is more engaging and realistic than what is normally encountered on television or film. The second educational goal is focused on developing a set of computational exercises to teach key materials science concepts to undergraduate engineering students in a more effective way. Computational skills are vital for engineering graduates entering the workforce, as engineering and manufacturing businesses increasingly rely on computational approaches in many areas of product development. By working in close collaboration with experts in materials informatics and undergraduate education, the PI will integrate computational materials and materials informatics research with this education initiative to equip engineering students with the skills they will need to succeed in the modern engineering workforce. TECHNICAL SUMMARYThis CAREER award supports theoretical and computational research that will unravel the microscopic mechanisms of ionic and thermal transport in the complex oxides materials family. The PI will use a combination of symmetry principles, simple crystal chemical models and first-principles calculations to uncover the fundamental knowledge that will facilitate the rational design of materials with tailored transport properties. First-principles techniques are crucial for the discovery of new ideas and insights into the ionic and thermal transport properties of materials because mechanistic details are typically not available from experiments alone. This research program will address several open questions related to the ionic and thermal transport properties of complex oxides. These include (i) the effects of dimensionality and atomic disorder on ionic transport in layered oxides, (ii) the strong coupling between specific structural distortions and ionic transport and the control of these distortions (and hence transport properties) in oxide thin-films through epitaxial strain, (iii) the role of electron-lattice interactions in reducing (lattice) thermal conductivity and (iv) the origin of the anomalously low thermal conductivity observed in some ferroelectric oxides. The educational component of this CAREER award has two goals. The first is to engage the general public and promote a more inclusive image of science by upending the popular stereotypes associated with scientists and their work. To achieve this goal, the PI will conduct public outreach in Austin highlighting stories and contributions of scientists that may be less well known to the general public. Such direct public outreach should allow the PI to portray the work of scientists in a way that is more engaging and realistic than what is normally encountered on television or film. The second educational goal is focused on developing a set of computational exercises to teach key materials science concepts to undergraduate engineering students in a more effective way. Computational skills are vital for engineering graduates entering the workforce, as engineering and manufacturing businesses increasingly rely on computational approaches in many areas of product development. By working in close collaboration with experts in materials informatics and undergraduate education, the PI will integrate computational materials and materials informatics research with this education initiative to equip engineering students with the skills they will need to succeed in the modern engineering workforce.