Designed synthesis of functionalized organic porous materials for catalysis and acid gas capture

PI: Mark Snyder

Co-PI(s): Srinivas Rangarajan

University: Lehigh University

Industry partners: Evonik, Johnson-Mathey, Ecovyst/Zeolyst

The burgeoning class of crystalline covalent organic frameworks (COFs) offers a tantalizing platform for the bottom-up design and synthesis of porous materials with precisely tailored pore size and topology, composition, and function. Realizing simultaneous control over these properties holds promise for transforming the efficiency and specificity with which COFs interact with molecular guests, thereby offering unprecedented control of reactions under confinement and enabling highly selective and efficient molecular separations among numerous other applications. This continuation project will exploit key design principles established in the FY21 stage of this work for realizing hierarchical porosity in COFs—namely, interconnected networks of macro/mesopores for rapid molecular access to confining crystalline pores. Such unfettered molecular accessibility of the crystalline COF pores is critical for 1) efficient and uniform post-synthetic addition of functional moieties throughout the COF pore topology, 2) rapid accessibility of molecular guests to catalytic or adsorptive sites within the COF pores, and 3) rapid counter diffusion of reaction products or sorbed molecules during sorbent regeneration. This continuation proposal aims to leverage this materials platform to develop critical synthesis-structure-functions relations governing COF-based acid catalysts and selective acid gas (e.g., CO2, NOx, H2S) sorbents—key to industrial applications at the center of critical advances in the energy and environment sectors. Comprehensive materials synthesis, characterization, and testing, informed by molecular scale simulations aimed at screening and classifying candidate functional groups, will help establish pre- and post-synthetic routes to tailoring pore function with molecular-scale resolution. Application of the resulting approach toward the selective, atomically resolved functionalization of COF pores should lead to unique multi-functional catalysts and sorbents. In addition to establishing industrially relevant materials, the proposed work aims to simultaneously provide insight into fundamental design questions surrounding synergies between pore confinement and function on catalysis and adsorption and building block functionality on assembly and COF crystallization.