CAREER: Fundamental Understanding of Thermal Transport at the Single Molecule Level

在纳米尺度上理解和控制物质、能量和信息是现代工程和科学的主要标志之一。原子和单分子器件代表了任何物理机器的小型化极限，并且具有创造前所未有的功能的巨大潜力，这些功能可以克服经典物理定律所设定的性能障碍。在分子尺度上直接探测热传输将阐明这些超小型化器件中的基本热传输机制和耗散极限，但仍然是一个巨大的技术挑战。该项目的主要目的是填补在单分子水平上理解热传输的知识空白。该项目的成果可能会改变目前的节能纳米电子和光子技术，并实现高性能热能和可再生能源材料的合理自下而上的设计方法。该项目还侧重于通过综合教育和推广计划，促进K-12和本科生的参与，特别是那些来自代表性不足的群体的参与，培训和多样化年轻一代的纳米工程师和热科学家。本项目的目标是建立一个全面的研究框架，用于单分子热传导和能量转换机制的基础研究。这项研究将使系统的测试，以解决长期悬而未决的问题，在分子热输运，虽然有一个长期的研究历史，从20世纪50年代开始，仍然在定性水平，由于缺乏实验基准数据。该项目利用了最近开发的具有热敏感性的扫描热显微镜，可以发现新的热效应，并从热的角度促进有机分子的创造性设计。实验研究将在一系列分子系统中进行，具体目的是揭示单一有机单体和聚合物热传输的结构-性能关系，并量化量子效应和热电分子的优值。该研究有望在分子声子学和量子热电学方面产生深刻的理解，并对热管理、分子电子学和热增强聚合物的材料设计领域产生深远的影响。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响评审标准进行评估，被认为值得支持。

Understanding and control of matter, energy, and information at the nanoscale is one of major hallmarks of modern engineering and sciences. Atomic and single-molecule devices represent the miniaturization limit of any physical machine, and have great potential to create unprecedented functionalities that overcome the performance barriers set by classical physical laws. Directly probing heat transport at the molecular scale will elucidate the fundamental thermal transport mechanisms and dissipation limits in these ultraminiaturized devices, but has remained as a great technological challenge. The principal aim of this project is to fill the knowledge gap in the understanding of thermal transport at the single molecule level. The outcomes of this project can potentially transform the current technologies of energy efficient nanoelectronics and photonics, as well as enable rational bottom-up design methods of high performance thermal and renewable energy materials. This project also focuses on training and diversifying the pool of young generations of nano-engineers and thermal scientists through an integrated education and outreach program that promotes the engagement of K-12 and undergraduate students, particularly those from underrepresented groups, in cutting-edge lab research, workshops, and hands-on learning.The goal of this project is to establish a comprehensive research framework for the fundamental study of heat conduction and energy conversion mechanisms in single molecules. This research will enable systematic tests to address long-standing open questions in molecular thermal transport, which although having a long research history starting from the 1950s, remain at a qualitative level due to the lack of experimental benchmarking data. This project leverages a recently developed scanning thermal microscope with ultrahigh sensitivity that allows the discovery of new thermal effects and promotes creative design of organic molecules from a thermal perspective. Experimental studies will be performed in a series of molecular systems with specific aims to reveal the structure-property relationships in thermal transport of single organic monomers and polymers, and to quantify quantum effects and the figure of merit of thermoelectric molecules. This research is expected to yield deep understanding in molecular phononics and quantum thermoelectrics, and profoundly impact the field of heat management, molecular electronics, and the material design of thermally-enhanced polymers.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.