David Burke (WPI-SKCM²): Leveraging Covalent Chemistry for the Assembly of Functional Porous Materials

Several of humanity’s greatest contemporary challenges have arisen due to the presence of small molecules in places where they are unwanted, such as the accumulation of carbon dioxide in the atmosphere, which drives climate change, and the contamination of water resources with chemical waste. Addressing these challenges will require the design and preparation of materials that can selectively sequester or separate molecules of interest from complex mixtures. One promising strategy to achieve precise molecular separations is to construct solid-phase materials that feature ordered nanoscale pores. Such void spaces approximate the sizes of small molecules, and can therefore facilitate molecular recognition, capture, or transport based on designed covalent or noncovalent interactions. Thus far, solid-phase porous materials have been primarily synthesized via two strategies. The first involves assembling rigid, geometrically-defined building blocks into two- or three-dimensional crystalline lattices, where the monomer connectivity defines the pore size and topology. More recently, discrete porous molecules, such as molecular cages, have been used as building blocks for amorphous polymer networks, where the intrinsic cavities of the cages are preserved after the polymerization event. In this presentation, recent advances in synthetic methodology for both classes of porous materials will be introduced, with a focus on application-relevant morphologies, such as thin films and gels. Additionally, the relative advantages and disadvantages of each material class, in terms of synthetic ease, processability, mechanical durability, and molecular uptake and separation performance, will be highlighted to emphasize opportunities for future research.