UNS: A Fundamental Study of Reversible and Giant Surface Activity on Soft Metals

1510772-DICKEY该奖项支持一种新型表面活性剂的基础研究，这种表面活性剂可以通过电子控制来操纵液态金属的形状和流动。这些液态金属是以镓合金为基础的，是汞的低毒替代品，汞是一种常见的液态金属，历史上一直受到其毒性的限制。这些金属像水一样是液体，但具有与金属相似的电学性质。这种特性的结合可以使电子设备变得柔软、可拉伸或形状可重新配置。提出的工作集中在一种新的方法来控制液态金属的形状，通过利用电信号来控制金属的表面性质，从而在小的长度尺度上操纵液态金属。利用低电压控制金属的形状或流动的能力可能使新型开关、天线、电线和电子成为可能。科学目标集中在理解这种通过在液态金属表面沉积(或去除)超薄氧化层来控制液态金属界面张力的新方法。与传统的表面活性剂(如肥皂或洗涤剂)不同，这种方法可以显著调节液态金属的界面张力(从~500mN/m到接近零)，快速且可逆，只需适度的电压(~1V)。这项拟议的工作试图通过三个任务来表征表面氧化物对界面张力的作用，以了解这个复杂的界面系统。这些研究将提供对软材料界面的新的基本理解，反过来，有助于将这一现象扩展到形成表面氧化物的其他材料，并使涉及使用低电压成形可重构金属的全新微观现象成为可能。这项工作还将确定表面氧化物作为一种新的流体表面活性剂的重要性，它带来了一些有史以来最大的表面张力变化。该项目将产生控制液态金属形状的新技术，从而使新型可重构光学、微流体和电子学成为可能。它还将为使用超越有毒汞的液态金属的新的创新机会奠定基础。这项研究将与一个名为“终结者的科学”的外展模块相结合，该模块在这部受欢迎的电影背景下描述液态金属。与北卡罗来纳州工程场所的伙伴关系将确保演讲具有适当的针对性和广泛的传播。该项目将在研究项目上整合本科生、高中学生和交换生，并将继续这样做，利用该项目的视觉吸引力来吸引学生。

1510772 - DickeyThis award supports fundamental research on a new class of surfactants that can be controlled electrically to manipulate the shape and flow of liquid metals. These liquid metals are based on alloys of gallium and provide a low-toxicity alternative to mercury, which is a common liquid metal that has been limited historically by its toxicity. These metals are liquids like water, yet have electrical properties similar to metals. This combination of properties could enable electronic devices that are soft, stretchable, or shape-reconfigurable. The proposed work focuses on a new method to control the shape of liquid metals by utilizing electrical signals to control the surface properties of the metal and thereby manipulate the liquid metal at small length scales. The ability to control the shape or flow of metals using low voltages may enable new types of switches, antennas, wires, and electronics.The scientific goals focus on understanding this new method to control the interfacial tension of liquid metal via electrochemical deposition (or removal) of an ultra-thin oxide layer on its surface. Unlike conventional surfactants (e.g., soaps or detergents), this approach can tune the interfacial tension of liquid metal significantly (from ~500 mN/m to near zero), rapidly, and reversibly using only modest voltages (~1 V). The proposed work seeks to understand this complex interfacial system by characterizing the role of the surface oxide on interfacial tension through three tasks. These studies will provide new fundamental understanding of soft material interfaces and in turn, help extend this phenomenon to other materials that form surface oxides as well as enable entirely new micro-scale phenomena involving shape reconfigurable metals using low voltages. The work will also establish the importance of surface oxides as a new class of fluid surfactants, which bring about some of the largest changes in surface tension ever reported.The project will produce new techniques to control the shape of liquid metals and thereby enable new types of reconfigurable optics, microfluidics, and electronics. It will also lay the foundation for new, innovative opportunities for the use of liquid metals that go beyond toxic mercury. The research will be integrated with an outreach module called "The Science of the Terminator" that describes liquid metals within the context of the popular motion picture. A partnership with the Engineering Place at NC State will ensure that the presentations are appropriately targeted and widely disseminated. The project will integrate undergraduate, high school, and exchange students on research projects and will continue to do so with this project by using the visually appealing nature of this project to attract students.