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Abstract Carbon capture and utilization or sequestration and direct air capture will be needed to reduce atmospheric levels of greenhouse gases over the next century. Current amine‐based technologies bind CO₂with high selectivities but suffer from poor oxidative and thermal stabilities. Herein, we discuss understudied sorbents based on oxygen nucleophiles, including metal oxides and hydroxides, hydroxide‐containing polymers, and hydroxide‐based metal–organic frameworks. In general, these materials display improved oxidative stabilities compared to traditional amine‐based sorbents. We outline the challenges and opportunities offered by these alternative sorbents for carbon capture applications. 

Metal–organic frameworks (MOFs) are crystalline materials that self-assemble from inorganic nodes and organic linkers, and isoreticular chemistry allows for modular and synthetic reagents of various sizes. In this study, a MOF’s components—metal nodes and organic linkers—are constructed in a coarse-grained model from isotropic beads, retaining the basic symmetries of the molecular components. Lennard-Jones and Weeks– Chandler–Andersen pair potentials are used to model attractive and repulsive particle interactions, respectively. We analyze the crystallinity of the self-assembled products and explore the role of modulators—molecules that compete with the organic linkers in binding to the metal nodes, and which we construct analogously—during the selfassembly process of defect-engineered MOFs. Coarse-grained simulation allows for the uncoupling of experimentally interdependent variables to broadly map and determine essential MOF self-assembly conditions, among which are properties of the modulator: binding strength, size (steric hindrance), and concentration. Of these, the simulated modulator’s binding strength has the most pronounced effect on the resulting MOF’s crystal size. 

Conjugated microporous polymers (CMPs) are porous organic materials that display (semi)conducting behavior due to their highly π-conjugated structures, making them promising next-generation materials for applications requiring both electrical conductivity and porosity. Currently, most CMPs and related porous aromatic frameworks (PAFs) are prepared using expensive transition metals (e.g., Pd), significantly increasing the costs associated with their synthesis. Lewis acid-mediated cyclotrimerization reactions of methyl ketones and nitriles represent promising and green alternative methods for CMP and PAF synthesis. Herein, we demonstrate that the generality of the solvent-free cyclotrimerization reactions is significantly improved by using ZnBr2 instead of ZnCl2 as the ionothermal medium. Specifically, we show that 1,4-diacetylbenzene (DAB), 4,4′-diacetylbiphenyl (DABP), 2,7-diacetylfluorene (DAF), 1,3,5-triacetylbenzene (TAB), tetrakis(4-acetylphenyl)methane (TAPM), and 1,4-dicyanobenzene (DCNB) can be polymerized in molten ZnBr2 to produce highly conjugated and microporous materials, as confirmed by 77 K N2 adsorption measurements, IR, and solid-state NMR. These findings support that ZnBr2 is an excellent Lewis acid mediator and medium for the ionothermal synthesis of porous organic materials.