CAREER: Hybrid Bronzes: Mixed-Valence Hybrid Metal Oxides as a Tunable Material Platform

职业：混合青铜：混合价混合金属氧化物作为可调材料平台

• 批准号: 2338086
• 负责人: Adam Jaffe
• 金额: $ 79.75万
• 依托单位: University of Notre Dame
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-02-01 至 2029-01-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2338086&HistoricalAwards=false
• 关键词: CAREER; Hybrid; Bronzes; Mixed; Valence

PART 1: Non-Technical SummaryRenewable energy technologies such as solar cells, batteries, and fuel cells are critical for addressing urgent global energy demand in a sustainable manner. These systems rely on materials that are highly stable and, as a function of their ordered structures, display important properties for energy-related use such as efficient light absorption and the ability to easily conduct electrical current. However, it is challenging and costly to synthesize and modify important crystalline solids such as metal oxides. The chemical tuning of molecules, on the other hand, is more precise and less energy intensive. With this CAREER award, supported by the Solid State and Materials Chemistry program in NSF’s Division of Materials Research, the principal investigator and his research group investigate how to combine the best qualities of molecules and materials by developing design principles for an emerging new class of organic-inorganic materials called hybrid bronzes. These easily synthesized, low-cost, and air-/water-stable compounds achieve atomic-level integration of metal oxide layers with molecules having adjustable functions, thereby providing a tunable material platform that can cater to numerous desired applications. This work elucidates structure-property relationships governing the electronic behavior of hybrid bronzes to inform their ultimate implementation in energy-related technologies. Furthermore, this interdisciplinary research program trains undergraduate and graduate students as the diverse future STEM workforce and develops a multi-faceted instructional video platform called "Lab Hacks" that seeks to lower resource and knowledge barriers in STEM education and research.PART 2: Technical SummaryHybrid bronzes are bulk crystalline materials that combine alternating layers of (1) mixed-valence metal oxide sheets featuring tunable charge-carrier densities and band gaps and (2) molecular arrays with the potential for chemical-, redox-, and photo-activity. Here, the term "bronze" refers to the metallic luster that quasi-free electrons impart to reduced metal oxides and it is these mobile carriers that ultimately enable such electronic versatility. To advance the hybrid bronze platform toward energy-related use, it is necessary to understand and subsequently control their redox activity, light absorption, and charge transport. Hybrid bronzes also represent versatile model systems that can probe questions regarding two-dimensional solid-state phenomena. With this CAREER award, supported by the Solid State and Materials Chemistry program in NSF’s Division of Materials Research, the principal investigator and his research group leverage mild aqueous self-assembly reactions to produce bulk crystalline hybrid bronzes with a fine degree of synthetic control. A suite of diffraction-based, spectroscopic, and electronic characterization techniques including high-pressure methods are then employed to elucidate structure-property relationships. Specifically, evaluation of systematically varied molecular structure-directing effects illuminates how charge transport is dictated within inorganic layers. Principles governing stimulus-driven charge transfer phenomena between molecules and layers are explored through optoelectronic, electrochemical, and charge transport analysis, followed by iterative molecular tuning. Further, pressure/strain-induced structure changes are employed as a unique approach to dictating electronic property transitions within hybrid bronzes. Overall, this work reveals connections between the structures and electronic behaviors of hybrid bronzes, including emergent phenomena, to demonstrate design rules enabling their customization.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.

第1部分：非技术摘要的可用能源技术，例如太阳能电池，电池和燃料电池对于以可持续的方式解决紧急的全球能源需求至关重要。这些系统依赖于高度稳定的材料，并且作为其有序结构的函数，显示了与能源相关使用的重要特性，例如有效的轻滥用以及轻松传导电流的能力。但是，合成和修改重要的结晶固体（例如金属氧化物）是具有挑战性的。另一方面，分子的化学调整更精确，能量密集型。在NSF材料研究部的固态和材料化学计划的支持下，首席研究员及其研究小组研究了如何通过为新兴新型有机无机材料的设计原理来结合分子和材料的最佳品质。这些易于合成，低成本和空气/水稳定的化合物与具有可调节功能的分子的金属氧化物层的原子水平整合，从而提供了可调材料平台，可以捕获许多所需的应用。这项工作阐明了结构性关系关系，负责混合青铜的电子行为，以告知其在能源相关技术中的最终实施。 Furthermore, this interdisciplinary research program trains undergraduate and graduate students as the divers future STEM workforce and develops a multi-faceted instructional video platform called "Lab Hacks" that seeks to lower resource and knowledge barriers in STEM education and research.PART 2: Technical SummaryHybrid bronzes are bulk crystalline materials that combine alternative layers of (1) mixed-valence metal oxide sheets featuring tunable charge-carrier密度和带隙以及（2）分子阵列，具有化学，氧化还原和光活性的潜力。在这里，“青铜”一词是指准无电子电子赋予金属氧化物还原的金属光泽，而这些移动载体最终使这种电子多功能性最终实现了。为了将混合铜平台推向与能源相关的使用，有必要理解并随后控制其氧化还原活动，轻滥用和电荷运输。混合青铜也代表了多功能模型系统，可以探究有关二维固态现象的问题。在NSF材料研究部的固态和材料化学计划的支持下，首席研究员及其研究小组利用轻度的自组装反应，以良好的合成控制生产散装的晶体杂化铜，并提供了良好的晶体杂化铜。然后聘请一套基于衍射的，光谱和电子表征技术（包括高压方法）的套件，以阐明结构 - 特质关系。具体而言，对系统变化的分子结构导向效应的评估阐明了电荷转运在无机层中的指示。通过光电，电化学和电荷传输分析，探索了分子和层之间刺激驱动的电荷转移现象的原理，然后进行迭代分子调整。此外，压力/应变诱导的结构变化是一种独特的方法来指示杂种青铜内的电子性质转变。总体而言，这项工作揭示了混合青铜器的结构和电子行为之间的联系，包括新兴现象，以演示实现其自定义的设计规则。该奖项反映了NSF的法定任务，并通过使用基金会的知识分子优点和更广泛的影响审查标准来通过评估来诚实地支持。