Innovative Tunable Optical Properties in Nanocrystal-based Films by Employing Mechanical Instabilities

利用机械不稳定性在纳米晶体薄膜中实现创新的可调谐光学特性

• 批准号: 1561964
• 负责人: Rebecca Anthony
• 金额: $ 39.92万
• 依托单位: Michigan State University
• 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: 2016-05-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1561964&HistoricalAwards=false
• 关键词: Innovative; Tunable; Optical; Properties; Nanocrystal

The future of technology for health monitoring, energy storage and use, and communications is moving towards flexible, bendable, and stretchable devices, including wearable devices and "electronic skins". To reach the maximum potential of these applications, there is a need to discover materials that exhibit exciting optical and electronic properties while remaining part of a mechanically flexible system. Nanocrystals present an ideal system to investigate for this purpose, as they have tunable electromagnetic absorption and emission properties, are easy and inexpensive to make, and can be integrated into thin films on stretchable substrates. Despite this, there have been few studies on the deformation behavior of these systems. This award supports research to create thin films of luminescent nanocrystals on deformable and flexible substrates, to measure their optical and mechanical properties, and to describe and predict the behavior of these films during flexion/stretching. The projected applications of these systems include forming optical metamaterials such as tunable gratings and filters, wearable sensors for body metrics, and flexible energy devices (e.g., light-emitting devices and solar photovoltaics). The research approach is to combine ideas across mechanical engineering, materials science, and nanotechnology to create a robust understanding of how layers of nanocrystals can be controllably deformed. This research will be used in year-round outreach events to inspire and educate future engineers including interactions with the general public and targeted events for underrepresented groups.Nanocrystals, used often in traditional rigid electronic devices, have the potential to withstand the strain of deformable device operation. Moreover, they can be made using environmentally friendly techniques and materials and exhibit exciting size-dependent properties such as luminescence. In addition, tunable wrinkling, due to instability formation, in thin films of nanocrystals on pre-stretched elastomeric substrates can be used to generate new electromagnetic and acoustic meta-materials. The problem is that the mechanical responses of nanocrystal films to stretching/flexion of the film substrate are almost completely unknown. This research will be devoted to experimentally and theoretically filling this knowledge gap. The research will include experimental studies on the mechanical behavior and instability formation in nanocrystal/substrate systems, depending on nanocrystal size and film porosity/thickness. These studies will be complemented by theoretical modeling of the mechanical properties of the systems to describe the instability formation. The research will then be integrated and used for predicting and designing the instabilities in nanocrystal films with ultimate application areas in stretchable electronics, sensors, and optical/acoustic metamaterials.

健康监测，能源存储和使用以及通信的技术未来正在朝着柔性，可弯曲和可拉伸设备（包括可穿戴设备和“电子皮肤”）迈进。为了达到这些应用的最大潜力，有必要发现材料表现出令人兴奋的光学和电子特性，同时剩下机械灵活的系统的一部分。纳米晶体提出了为此目的进行调查的理想系统，因为它们具有可调的电磁吸收和发射特性，易于制造，并且可以将其整合到可拉伸底物上的薄膜中。尽管如此，关于这些系统的变形行为的研究很少。该奖项支持研究，以在可变形和柔性底物上创建发光纳米晶体的薄膜，以测量其光学和机械性能，并描述和预测屈曲/拉伸过程中这些膜的行为。 这些系统的预计应用包括形成光学超材料，例如可调光栅和过滤器，身体指标的可穿戴传感器以及柔性的能量设备（例如，发光设备和太阳能光伏电动机）。研究方法是结合跨机械工程，材料科学和纳米技术的思想，以对如何可以控制纳米晶体的层层有深入的了解。这项研究将在全年的外展活动中使用，以激发和教育未来的工程师，包括与普通公众和有针对性不足的群体的互动。纳米晶体经常在传统的刚性电子设备中使用，有可能承受可变形设备操作的压力。此外，它们可以使用环保技术和材料制成，并表现出令人兴奋的尺寸依赖性特性，例如发光。此外，由于不稳定的形成，可调节的皱纹在预拉伸的弹性体底物上的纳米晶体薄膜中可用于生成新的电磁和声学元材料。问题在于，纳米晶膜对膜底物的拉伸/屈曲的机械响应几乎完全未知。这项研究将致力于实验和理论上填补这一知识差距。该研究将包括有关纳米晶/底物系统机械行为和不稳定性形成的实验研究，具体取决于纳米晶体的大小和膜孔隙度/厚度。这些研究将通过系统的机械性能来描述不稳定性形成的理论建模。 然后，该研究将集成并用于预测和设计纳米晶体膜中的不稳定性，并在可伸缩电子，传感器和光学/声学超材料中具有最终的应用区域。