RUI: Mechanistic Elucidation of the Formation of Metal-organic Frameworks: A Spectroscopic, Synthetic, and Computational Approach

NON-TECHNICAL SUMMARY: Metal-organic frameworks (MOFs) are a class of materials that have shown promise in several industrially and societally relevant applications including carbon capture, water purification, and catalysis. Except for select examples, the development of general and robust large-scale syntheses of MOFs has proven elusive, limiting broad implementation to the greater community. Current efforts to optimize MOF syntheses for scale-up often focus on trial-and-error type approaches that can be time-consuming and costly. With this project, supported by the Solid State and Materials Chemistry Program in the Division of Materials Research, Prof. Douglas Genna and his research group at Youngstown State University combines the tools of synthesis, spectroscopy, and computational modeling to develop mechanistic models of both successful and unsuccessful MOF synthesis reactions. These mechanistic models will identify the necessary chemical species for success and elucidate the deleterious species that lead to failed synthesis attempts. This information can then be used by the practitioner to develop robust synthesis protocols for existing MOF materials and provide opportunity and guidance for the exploration of new chemical spaces while limiting guesswork. An online lecture series is being developed to increase scientific and chemical literacy in adults. TECHNICAL SUMMARY: MOFs are a class of materials that continue to show promise in areas such as catalysis, drug delivery, molecular separations, and energy storage, amongst others. While exceptional work has been performed on the mechanisms of MOF self-assembly this remains an under-studied area of research. This project, supported by the Solid State and Materials Chemistry Program in the Division of Materials Research, focus on understanding the solution-phase mechanism of formation of metal-organic frameworks (MOFs). Specifically, MOFs composed of group 13 metals (Al, Ga, and In) are studied using the tools of synthesis, density functional theory (DFT), and in-situ Raman spectroscopy. The formation of In-derived infinite chains and cationic trimers (Objective 1) and anionic Ga-MOFs (Objective 2) is studied using DFT to identify potential molecular and polymer intermediate targets for synthesis. The presence of said intermediates in solution is interrogated using in-situ Raman spectroscopy. Solution-phase and solid-state non-MOF products of unsuccessful MOF syntheses (Objective 3) are studied using Raman spectroscopy, powder-X-ray diffraction, nuclear magnetic resonance, DFT, and synthesis when appropriate. 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.