LEAPS-MPS: Seeking Superlubricity at Single Molecule Level on Graphene Nanoribbons

该奖项全部或部分由2021年美国救援计划法案（公法117-2）资助。非技术性摘要：摩擦是一种基本的物理现象。走路或开车都不可能没有摩擦力。另一方面，摩擦对机械设备有负面影响，因为它会导致磨损，消耗能量，浪费不可再生的自然资源。该项目旨在研究有机分子和石墨烯纳米带（GNRs）形成的接触的超润滑性，即摩擦几乎消失的状态。通过测量有机分子在GNRs上滑动时的摩擦力，该项目研究了原子尺度下的摩擦定律，并探索了超润滑性的起源，以补充高中教科书中的宏观摩擦定律，并旨在实现摩擦学的突破。该项目可能导致GNRs作为超润滑单层材料，用于减少自旋电子器件和其他微纳米机电系统的摩擦和磨损。该项目是Old自治领大学（ODU）在单原子/分子水平上的第一个物理和材料项目。它将ODU引入到以前在校园无法访问的研究专业知识和仪器资源中，并扩大了来自各个科学和工程领域的教师和学生的研究参与。这项研究还旨在激发年轻人的思想，涉及ODU研究生，大量来自少数民族的ODU本科生，由汉普顿路社区的非裔美国学生组成的黑人物理学家协会（SBP）的学生，以及来自周边地区的K-12高中生。技术摘要：该项目利用GNRs作为固态支撑平台来容纳有机分子，使用低温扫描隧道显微镜（STM）和qPlus原子力显微镜（Q+AFM）量化GNRs上移动单个分子所需的力，旨在发现GNRs上的超润滑性，其静摩擦力比以前观察到的小1-2个数量级。在三种不同类型的GNR之上，研究了各种分子系统，包括单一有机分子、平面和非平面、结构对称和非对称，以揭示原子尺度摩擦和超润滑性的起源。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).NONTECHNICAL ABSTRACT: Friction is an essential physical phenomenon. It would be impossible to walk or drive without friction. On the other hand, friction has negative impacts on mechanical devices because it causes wear, dissipates energy, and wastes non-renewable natural resources. This project aims to investigate superlubricity, a state where friction almost vanishes, on the contacts formed by organic molecules and graphene nanoribbons (GNRs). By measuring friction force on organic molecules sliding on GNRs, the project investigates the laws of friction at atomic scale and explores the origins of superlubricity, to complement the macroscopic laws of friction available in high school textbook and to aim for breakthroughs in tribology. The project may lead to GNRs as superlubricant monolayer materials applied to reduce the friction and wear of spintronic devices and other micro- and nano-electromechanical systems. The project is the first on physics and materials at the single atom/molecule level at Old Dominion University (ODU). It introduces ODU to research expertise and instrumentation resources not previously accessible on campus, and it broadens research participation among faculty and students from various science and engineering fields. This research also aims to inspire young minds, involving an ODU graduate student, a large number of ODU undergraduate students from minority groups, students from the Society of Black Physicists (SBP) formed by African American students in the Hampton Roads community, as well as K-12 high school students from the surrounding area. TECHNICAL ABSTRACT: The project utilizes GNRs as solid-state supporting platforms to accommodate organic molecules, to quantify the force required to move a single molecule on GNRs using a low temperature Scanning Tunneling Microscope (STM) and a qPlus Atomic Force Microscope (Q+AFM), and aims to discover superlubricity on GNRs with static friction 1-2 orders of magnitude smaller than previously observed. Various molecular systems including single organic molecules, planar and non-planar, symmetric and non-symmetric in structure, on top of three different types of GNRs are investigated to unveil the origins of atomic scale friction and superlubricity.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.