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

Old Dominion University Research Foundation, Norfolk VA

Investigators

Abstract

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.