Patterning Mesoscale Chirality by Guided Crystal Twisting

通过引导晶体扭曲形成中尺度手性图案

• 批准号: 2325911
• 负责人: Stephanie Lee
• 金额: $ 52.45万
• 依托单位: New York University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-03-01 至 2027-02-28
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2325911&HistoricalAwards=false
• 关键词: Patterning; Mesoscale; Chirality; Guided; Crystal

Silicon-based semiconductor crystals for computer chips and solar panels epitomize our reliance on crystalline materials and underscore their centrality for information technologies and renewable energies. While defect-free single crystals are the gold standard for most applications, bundles of imperfect, interacting crystals can be superior in some cases. This grant supports research on how organic semiconductor crystals can be fabricated as networks of twisted braids that counterintuitively outperform single crystals in the transport of electrons and detection and emission of different types of light. These twisted crystals are formed from the melt, making it possible to leverage high throughput fabrication methods. These novel materials support plastic electronics industries based on flexible light emitting diodes and displays, transistors, and wearable electronics for sensing and health monitoring thus augmenting the U.S. economy. At the intersection of solid-state physics, materials science, and process engineering, this multidisciplinary research serves as a rich training platform for undergraduate and graduate students, contributing to workforce development as called for by the CHIPS and Science Act. The colorful patterns created by twisted crystals form the basis of interactive STEAM workshops at the K-12 level. Through this activity, students learn about the concepts of crystals and light-matter interactions.Designing materials for chiroptoelectronics has relied on the synthesis of chiral molecules enantioselectively or the labor- and atom-intensive resolution of racemic mixtures of enantiomers. Twisted crystals that form spontaneously from the melt can manifest mesoscale chiroptical properties. The challenges facing the advancement of twisted crystals for chiroptoelectronics are the lack of spatial control over the twist sense and direction, and the incompatibility of current batch processing with high throughput manufacturing. This research articulates mechanisms governing twisted crystal formation and how the organization of crystal fibers affects electron and photon transport. This understanding guides the development of scalable processing methods to fabricate twisted crystal films with prescribed orientations and twist sense. Hybrid screw extrusion and roll-to-roll coating of molten material into patterned films are investigated as a scalable manufacturing method for these chiroptoelectronic materials. This continuous processing method involves inline mixing of molecular compounds and twisting additives prior to extrusion; precise control over film thickness, crystallization temperature, and shear profile; and tunable patterning using corrugated rollers. Newly developed rapid differential polarization imaging for inline characterization during film coating permits the screening and optimization of hundreds of electro-optical thin films made of collimated twisted crystal films. Examples of the applications of twisted crystals are circularly polarized light detectors and waveguides.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.

用于计算机芯片和太阳能电池板的基于硅的半导体晶体代表了我们对晶体材料的依赖，并强调了其对信息技术和可再生能量的中心地位。虽然无缺陷的单晶是大多数应用的金标准，但在某些情况下，相互作用的晶体束可以优越。该赠款支持有关如何将有机半导体晶体作为扭曲编织网络制造的研究，这些网络在电子传输以及检测和发射不同类型的光线时的表现优于单晶的表现。这些扭曲的晶体是由熔体形成的，可以利用高通量制造方法。这些新颖的材料基于柔性的发光二极管和显示，晶体管和可穿戴电子产品来支持塑料电子行业，以感知和健康监测，从而增强了美国经济。在固态物理，材料科学和过程工程的交集中，这项多学科研究是本科生和研究生的丰富培训平台，为筹码和科学法所要求的劳动力发展做出了贡献。扭曲晶体创建的彩色图案构成了K-12级别的交互式蒸汽研讨会的基础。通过这项活动，学生了解了晶体和光 - 物质相互作用的概念。授权电子学的设计材料依赖于手性分子对映射的合成，或者是对对照媒介的外消毒混合物的劳动和原子密集型分辨率。从熔体自发形成的扭曲晶体可以表现出中尺度的手势特性。扭曲晶体在脊椎展上的发展所面临的挑战是缺乏对扭曲感和方向的空间控制，以及当前批处理处理与高吞吐量制造的不相容性。这项研究表达了管理扭曲晶体形成的机制，以及晶体纤维的组织如何影响电子和光子传输。这种理解指导了可扩展的加工方法的开发，以使用规定的方向和扭曲感制造扭曲的晶体膜。研究了这些chiroptotoelectronic材料的一种可扩展的制造方法，研究了将熔融材料挤压到图案化膜中的混合螺钉挤出和卷到卷涂层。这种连续的加工方法涉及在挤出之前的分子化合物和扭曲添加剂的内联混合。精确控制膜厚度，结晶温度和剪切轮廓；并使用波纹辊可调图案。新开发的快速微分极化成像，用于在膜涂层期间内联表征，可以筛选和优化数百种由准直扭曲晶体制成的电流薄膜。扭曲晶体的应用的例子是循环极化的光检测器和波导。该奖项反映了NSF的法定任务，并且使用基金会的知识分子优点和更广泛的影响审查标准，被认为值得通过评估来获得支持。