This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).<br/><br/>Non-Technical Abstract<br/>Covalent organic frameworks (COFs) are a diverse field of crystalline two-dimensional polymers that have highly tunable properties due to the geometry of the bonding between components and variability in the nature of the bond and functional groups present on the reactant molecules. The formation of COFs “under confinement” has been studied at a variety of interfaces, but not for reactants trapped between two solid surfaces. Graphene is a single layer of covalently linked carbon atoms that is easily exfoliated from graphite and can trap highly mobile molecules at solid surfaces. With this LEAPS-MPS project, Professor Ryan Brown’s research group at Clarkson University investigates trapping reactants between graphene and a solid surface to study COF formation at a solid-solid interface. They look at how COF growth changes when reactants are confined between solid interfaces. Some COF linkages are not easily formed through a direct condensation reaction at surfaces or in solution due to competing reactions or desorption at the high-temperatures. Prof. Brown’s group employes graphene confinement as a strategy for carrying out these inaccessible reactions, as well as using graphene trapping to pattern COF growth for linkages not normally formed through direct condensation reactions. In addition to the science aspects, the project also engages underrepresented communities within the Mathematical and Physical sciences field through seminar invitations for pre-tenure faculty, professional development workshops for undergraduate students from underrepresented backgrounds, and the provision of paid research experience for high school students from the local indigenous communities.<br/><br/>Technical Abstract<br/>The growth of two-dimensional covalent organic frameworks (COFs) confined at a variety of interfaces is an active field with a variety of outcomes based on the nature of the confinement. So far though, the existing body of work in this field does not address the consequences of forming 2D-COFs under confinement by a solid-solid interface. Understanding COF growth confined between solid-solid interfaces is important for assessing the viability of employing this class of materials as intercalation species to modify the chemical, optical, or electrical properties of two-dimensional materials such as transition metal dichalcogenides and MXenes. With this LEAPS-MPS project, Professor Ryan Brown’s research group explores the impact of physical confinement between solid surface on COF growth by employing scanning probe microscopy (SPM), spatially-resolved Fourier transform infrared spectroscopy (FTIR), and density functional theory calculations to assess changes in the mobility and reactivity of COF precursors confined between exfoliated graphene and solid interfaces. Exfoliated graphene can confine gases, liquids, and small molecules at solid interfaces, and the graphene-mica and graphene-Au(111) interfaces are used as experimentally accessible model systems for confinement at a solid-solid interface. Professor Brown’s research group investigates the impact of a graphene capping layer on the growth and morphology of COFs formed from common condensation reactions for single and multiple reactant systems. This work also extends to assessing the viability of using graphene confinement at surfaces to produce COF linkages not readily accessible through direct condensation reactions. Additionally, Professor Brown works with existing organizations within Clarkson University to enhance the mentoring, training, and career progression undergraduate students and pre-tenure faculty members from underrepresented backgrounds in Mathematical and Physical Sciences through a series of enrichment activities and research opportunities. High school students from the northern New York indigenous communities gain valuable research exposure and experience through this program, as well.<br/><br/>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.