DMREF: Collaborative Research: Materials Design of Correlated Metals as Novel Transparent Conductors

DMREF：合作研究：相关金属作为新型透明导体的材料设计

• 批准号: 1629346
• 负责人: Karin Rabe
• 金额: $ 24万
• 依托单位: Rutgers University New Brunswick
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-10-01 至 2020-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1629346&HistoricalAwards=false
• 关键词: DMREF; Collaborative; Research; Materials; Design

NON-TECHNICAL DESCRIPTION: Transparent conductors are a critical component in many technologies affecting society, including solar cells, touch screens, flat panel displays, light emitting diodes and lasers. Finding materials that combine high electrical conductivity with excellent optical transparency in the visible spectrum has proved challenging: metals typically are good conductors but reflect rather than transmit visible light, while insulators like glass are highly transparent but do not carry an electrical current. The goal of this project is to pursue an unconventional paradigm, developed in previous work by members of the project team, to discover and develop new transparent conducting materials based on earth-abundant elements that exhibit substantially better performance and can be made with lower cost than the long-standing industry-standard indium-tin-oxide (ITO). Theoretical analysis combining mining of databases of materials property measurements and computations with predictive simulations of the structure and properties of candidate materials will be closely integrated with efforts in the laboratory to synthesize, characterize and optimize real materials. In the context of the Materials Genome Initiative coordinating efforts across the nation to accelerate the discovery, development and deployment of advanced materials, tools and techniques for integration of theory and experiment in materials design that are developed in the course of the project will be made available to the community to advance progress in broader materials design challenges. Breakthroughs in the development of transparent conductors will advance green technologies for energy generation, lighting, and passive building designs.TECHNICAL DESCRIPTION: The conventional paradigm to combine the contradicted properties of transparency and high electrical conductivity is to heavily dope a wide band gap ? thus transparent ? semiconductor to increase its electrical conductivity. Rather than making a transparent semiconductor more conductive, the idea of the new paradigm is to make a metal optically transparent. This can be done by increasing the electron effective mass by correlation effects, which reduces the metal reflectivity in the visible range, in targeted systems for which interband transitions are above the visible range. The design space for the discovery of new transparent conductors spans a wide range of families, including correlated oxides, layered chalcogenides, pnictides, and intermetallic compounds. A hierarchical three-level search approach will be pursued. First, material candidates will be pre-screened in the available materials design space using simple-to-apply qualifier criteria, followed by high-throughput first-principles computations of crystal structure, electronic bands, and quantities related to optical and electrical transport properties at the level of density functional theory (DFT). At the third level, correlation effects will be studied within density functional mean field theory (DMFT) to refine the lower level search criteria and identify the most promising systems for further investigation. In the laboratory, synthesis and characterization of the electrical transport and optical properties of these candidate materials and comparison with theoretical predictions will aid in the refinement of design principles and the expansion of the set of transparent conducting materials available for technological applications.

非技术描述：透明导体是影响社会的许多技术的关键组件，包括太阳能电池、触摸屏、平板显示器、发光二极管和激光。事实证明，寻找在可见光光谱中结合高导电性和极佳光学透明度的材料具有挑战性：金属通常是良好的导体，但反射而不是透过可见光，而玻璃等绝缘体高度透明，但不携带电流。该项目的目标是追求项目组成员在以前的工作中开发的非传统范式，以地球上丰富的元素为基础发现和开发新的透明导电材料，这些元素表现出更好的性能，并且可以比长期存在的行业标准铟锡氧化物(ITO)更低的成本制造。理论分析将材料性能测量和计算数据库的挖掘与候选材料的结构和性能的预测模拟相结合，将与实验室合成、表征和优化真实材料的努力紧密结合。在材料基因组倡议的背景下，协调全国各地的努力，以加快发现、开发和部署先进材料，在该项目过程中开发的材料设计理论和实验集成的工具和技术将向社区提供，以推动在更广泛的材料设计挑战中取得进展。透明导体开发方面的突破将推动绿色发电、照明和被动建筑设计的技术。技术描述：将透明度和高导电性的矛盾特性结合在一起的传统范例是大量掺杂宽禁带？如此透明？半导体，以提高其导电性。新范式的想法不是让透明半导体更具导电性，而是让金属在光学上变得透明。这可以通过相关效应增加电子的有效质量来实现，相关效应降低了目标系统中的金属在可见光范围内的反射率，目标系统的带间跃迁高于可见范围。为发现新的透明导体而设计的空间跨越了广泛的家族，包括相关氧化物、层状硫化物、锡石和金属间化合物。将采取分级的三级搜索方法。首先，将使用易于应用的限定符标准在可用的材料设计空间中对候选材料进行预筛选，然后在密度泛函理论(DFT)水平上对晶体结构、电子能带以及与光学和电学输运性质相关的量进行高通量第一原理计算。在第三个水平，将在密度泛函平均场理论(DMFT)中研究关联效应，以完善较低水平的搜索标准，并确定最有希望进行进一步研究的系统。在实验室中，合成和表征这些候选材料的电输运和光学性质，并与理论预测进行比较，将有助于完善设计原则，扩大可用于技术应用的透明导电材料集。