RUI: Confronting Structural Complexity in the Computational Design and Understanding of Perovskite Materials for Solar Energy Conversion

RUI：计算设计中的结构复杂性和对太阳能转换钙钛矿材料的理解

• 批准号: 2026970
• 负责人: Robert Berger
• 金额: $ 26.81万
• 依托单位: Western Washington University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-01-01 至 2024-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2026970&HistoricalAwards=false
• 关键词: RUI; Confronting; Structural; Complexity; Computational

NONTECHNICAL SUMMARYThis RUI award supports computational research to design and understand "perovskite" compounds, a technologically important class of materials with the ability to absorb and harness the energy in sunlight. Perovskite compounds have the general formula ABX3, meaning they consist of three chemical elements in a 1:1:3 ratio. In the past decade, some of these compounds have shown promise in photovoltaic solar cells, meaning they can convert sunlight directly to electricity. Other perovskites are solar photocatalysts, meaning they can use sunlight to drive chemical reactions that generate fuel. A unique property of perovskites is that their structure can be changed in many subtle ways -- substituted with different elements, pulled and twisted, layered and decorated -- to optimize their ability to convert sunlight. With all of this freedom to modify perovskites, computers are valuable tools in predicting which of these materials will behave in desired ways. In this research, the principal investigator (PI), undergraduate, and master's-level students will use computers to predict how and understand why substitutions and movements of atoms affect the ability of perovskites to absorb and convert sunlight. In addition, the research group will develop a new computational method, faster than traditional methods, to quickly and roughly search the huge variety of perovskite materials for properties of interest.The award also supports the PI's mentoring and teaching activities and curriculum development at Western Washington University, a primarily undergraduate institution. The award will enable the training and mentoring of a diverse group of undergraduate and master's students along with opportunities for the PI and students to present their work at regional and national research conferences. In recent years, the PI has worked to "flip" his undergraduate physical chemistry courses, designing in-class problem solving and computer simulation activities to engage students in more active ways. There is evidence in the education literature that this approach leads to a variety of positive learning outcomes (especially among lower-performing students) and promotes equity and inclusion by engaging students with a wide spectrum of different learning styles. In the coming years, the PI will refine and further develop these curricular materials for physical chemistry and develop similar student-centered training materials relevant to his group's research areas. These materials will help students learn about fields such as computational and solid-state chemistry, which are rarely covered in the undergraduate curriculum.TECHNICAL SUMMARYThis RUI award supports computational research to design and understand perovskite compounds for solar energy conversion. In the past decade, halide perovskite solar cells have emerged as a promising and rapidly developing technology. So too have oxide perovskites been explored for solar photocatalysis. Along with advances in synthesis and device engineering, there have been density functional theory (DFT)-based studies of various aspects of the structure and properties of these materials. However, due in large part to the structural complexity of experimentally relevant perovskite superstructures and nanostructures, cases in which theory and computation have truly been on the leading predictive edge of this field have been limited. In order to advance fundamental understanding of structure/property relationships and guide experimentalists in the search for new materials, the PI, undergraduate, and master's-level students will study three research areas in the computational elucidation and design of halide and oxide perovskites. These projects will use electronic structure calculations to: 1) tune electronic properties using strain and its couplings to composition and structural distortion; 2) identify novel, energetically stable classes of perovskite superstructures with desired properties; 3) develop, test, and deploy a new semi-empirical approach (based on the extended Hueckel method) to the rapid high-throughput screening of complex perovskite superstructures and nanostructures. These projects will advance the state of the field in terms of fundamental understanding, discovery and tuning of new materials, and method development.The award also supports the PI's mentoring and teaching activities and curriculum development at Western Washington University, a primarily undergraduate institution. The award will enable the training and mentoring of a diverse group of undergraduate students (with nine summer research stipends over three years) and a master's student, and opportunities for the PI and students to present their work at regional and national research conferences. Students will learn about renewable energy and key areas of chemistry (computational and solid state) that are rarely seen in the undergraduate curriculum, and will gain computational skills (Linux and programming) that are increasingly valued in the modern workforce. In parallel with these research efforts, the PI will develop and assess synergistic educational materials for students, in the form of standalone computer simulation lessons in key topics of solid state chemistry (e.g., crystal structure and symmetry, X-ray diffraction, and electronic band structure and reciprocal space). These lessons are an outgrowth of the suite of computer simulation lessons that the PI has developed and used in student-centered activities in undergraduate physical chemistry courses.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.

非技术摘要This RUI奖支持计算研究，以设计和理解“钙钛矿”化合物，这是一种具有技术重要的材料类，具有吸收和利用阳光的能量的能力。钙钛矿化合物具有一般式ABX3，这意味着它们由1：1：3的三个化学元素组成。在过去的十年中，其中一些化合物在光伏太阳能电池中表现出了希望，这意味着它们可以将阳光直接转化为电。其他钙钛矿是太阳能光催化剂，这意味着它们可以使用阳光来驱动产生燃料的化学反应。 Perovskites的独特属性是，它们的结构可以通过多种微妙的方式进行更改（用不同的元素代替，拉动和扭曲，分层和装饰），以优化它们转化阳光的能力。凭借所有这些修改钙钛矿的自由，计算机是预测这些材料中的哪一种工具的宝贵工具。在这项研究中，首席研究员（PI），本科生和硕士级别的学生将使用计算机来预测以及理解原子的替代和运动为什么会影响钙钛矿吸收和转化阳光的能力。此外，研究小组将开发一种新的计算方法，比传统方法更快，以快速而粗略地搜索各种各样的钙钛矿材料，以获取感兴趣的属性。该奖项还支持西部华盛顿大学（主要是本科生机构）的PI的指导和教学活动和课程开发。该奖项将使多样化的本科生和硕士学生培训和指导，以及PI和学生在区域和国家研究会议上介绍他们的作品的机会。近年来，PI致力于“翻转”他的本科生化学课程，设计在课堂上解决问题和计算机模拟活动，以更积极的方式吸引学生。教育文献中有证据表明，这种方法会导致各种积极的学习成果（尤其是在表现较低的学生中），并通过吸引各种不同学习风格的学生来促进公平和包容。在接下来的几年中，PI将完善并进一步开发这些课程材料，以用于物理化学，并开发与该小组研究领域相关的以学生为中心的培训材料。这些材料将帮助学生了解诸如计算和固态化学之类的领域，这些领域很少在本科课程中涵盖。技术摘要rui奖支持计算研究，以设计和理解太阳能转换的钙钛矿化合物。在过去的十年中，卤化物钙钛矿太阳能电池已成为一种有前途且迅速发展的技术。氧化物钙钛矿也被探索用于太阳光催化。随着合成和设备工程的进步，还基于密度功能理论（DFT）对这些材料的结构和特性的各个方面进行了研究。但是，在很大程度上是由于实验相关的钙钛矿上层建筑和纳米结构的结构复杂性，其中理论和计算真正位于该领域的领先预测边缘的情况受到限制。为了促进对结构/财产关系的基本理解，并指导实验者在寻找新材料时，PI，本科生和硕士学位的学生将研究在卤化卤化物和氧化物perovskites的计算阐明和设计中的三个研究领域。这些项目将使用电子结构计算为：1）使用应变及其耦合对组成和结构失真调整电子性能； 2）确定具有所需特性的新型，能量稳定的钙钛矿上层建筑； 3）开发，测试和部署一种新的半经验方法（基于扩展的Hueckel方法），以快速对复杂的钙钛矿上层建筑和纳米结构的快速高通量筛选。这些项目将在对新材料的基本理解，发现和调整以及方法开发方面的基本理解，发现和调整。该奖项将使多样化的本科生培训和指导（在三年内拥有9个夏季研究津贴）和一名硕士学生，以及PI和学生有机会在区域和国家研究会议上介绍他们的作品。学生将了解在本科课程中很少见的可再生能源和化学的关键领域（计算和固态），并将获得现代劳动力越来越重视的计算技能（Linux和编程）。与这些研究工作同时，PI将以独立的计算机模拟课程的形式开发和评估学生的协同教育材料（例如固态化学的关键主题（例如，晶体结构和对称性，X射线衍射，电子带结构和相互空间））。这些课程是PI在本科生化学课程中开发和使用的计算机模拟课程的产物。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛影响的审查标准来通过评估来获得支持的。

项目成果

Tuning the Band Gaps of Oxide and Halide Perovskite Compounds via Biaxial Strain in All Directions

• DOI: 10.1021/acs.jpcc.1c07169
• 发表时间: 2021-11
• 期刊: The Journal of Physical Chemistry C
• 作者: Corey Teply;B. Tyler;R. Berger