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。原子和单分子设备代表了任何物理机器的小型化极限，并具有巨大的潜力，可以创造出前所未有的功能，克服经典物理定律设置的性能障碍。直接探测分子尺度上的热输运将阐明这些超小型化器件的基本热输运机制和耗散极限，但这仍然是一个巨大的技术挑战。这个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当前的能效纳米电子和光子学技术，并使高性能热能和可再生能源材料的合理自下而上设计方法成为可能。该项目还专注于通过综合教育和推广计划培养和多样化年轻一代的纳米工程师和热学科学家，该计划旨在促进K-12和本科生，特别是来自代表性不足群体的本科生，参与尖端实验室研究、研讨会和实践学习。该项目的目标是为单分子热传导和能量转换机制的基础研究建立一个全面的研究框架。这项研究将使系统测试能够解决分子热传输中长期存在的悬而未决的问题，尽管从20世纪50年代开始就有很长的研究历史，但由于缺乏实验基准数据，这些问题仍处于定性水平。该项目利用最近开发的具有超高灵敏度的扫描热显微镜，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，目的是揭示单一有机单体和聚合物在热传输过程中的结构-性质关系，并量化热电分子的量子效应和优值系数。这项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优势和更广泛的影响审查标准进行评估，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.