Self-Assembled Metal-Organic Framework Monolayers (SAMMs)

NON-TECHNICAL ABSTRACT With the support of the Solid State and Materials Chemistry Program in NSF’s Materials Research Section A, Professor Seth Cohen of the University of California, Irvine (UCI) studies composite materials comprised of polymer and porous solid materials. Next-generation materials are essential to nearly every aspect of modern life and technological innovation, including transportation, communications, electronics, computing, health, national security, energy, and others. Blending materials with very different characteristics, such as pliable, moldable polymers (e.g., plastics) and brittle solids (e.g., ceramics, carbons, etc.), can produce composites that combine the best properties of both materials and ideally, generate materials with emergent, new characteristics. However, the very different characteristics makes combining disparate materials challenging. In this effort, a class of solids known as metal-organic frameworks (MOFs) will be coated with polymers to form a new material referred to as self-assembled MOF monolayers (a.k.a., SAMMs). MOFs were recognized with the 2025 Nobel Prize in Chemistry. As part of this project the researchers synthesize composites of MOFs and investigate fundamental structure-property correlations to advance the fundamental understanding of such composites in the form of flexible, ultrathin films. These films could serve as coatings, membranes, and allow for integration of MOFs into devices and new technologies. In addition to these scientific studies, this program supports undergraduate students from across the University of California system to travel to Washington, DC, where they can participate in internships at the interface of public policy and science through the Science Policy Internship Program (SPIP), as well as an annual symposium for postdoctoral researchers at UCI. TECHNICAL ABSTRACT Combining organic polymers and metal-organic frameworks has proven an important area of research for the development of hybrid, composite materials that possess attractive and emergent properties. This effort, supported by the Solid State and Materials Chemistry Program in NSF’s Materials Research Section A, explores the synthesis, characterization, and application of self-assembled MOF monolayers (a.k.a., SAMMs). SAMMs are porous metal-organic frameworks (MOFs) that are coated with polymers that can form ultrathin films and membranes using interfacial self-assembly methods. With this project, researchers study: the influence of the MOF particle composition, size, and shape on the formation of SAMMs; the polymer composition and interactions on SAMM self-assembly and characteristics; and employ polymer crosslinking to augment interparticle interactions in SAMMs to make more robust ultrathin films. SAMMs are prepared using cutting-edge materials synthesis approaches and characterized by various spectroscopic methods, gel-permeation chromatography (GPC), thermal analysis (TGA, DSC), scanning- and transmission-electron microscopy (SEM, TEM), and a suite of other methods. Ultimately, the findings from these studies might have the potential to advance SAMMs as an innovative class of MOF-polymer composites that can help translate these hybrid materials into applications that support the economic prosperity, defense, and technological superiority of the nation. 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.