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We quantified solid–water partitioning as a function of pH and the extent of desorption for a diverse set of per- and polyfluoroalkyl substances (PFASs) on two iron oxide minerals and two silica clay minerals. 

Compared to conventional methods, direct light-driven separations are promising strategies to achieve high selectivity while lowering energy cost. 

A common strategy for developing emissive covalent organic frameworks (COFs) with varied properties is incorporating diverse chromophoric monomers. Herein, an alternative approach is adopted to demonstrate that a simple alteration in just one atom (oxygen vs. sulfur) in monomer design can result in significant differences in the physical, chemical, and photophysical properties of the resulting COFs. Specifically, monomers with the same symmetry but containing either urea or thiourea functionalities are used to synthesize two crystalline, fully conjugated emissive COFs,COF‐SMU‐2(urea‐based), andCOF‐SMU‐3(thiourea‐based), withsqltype topology. Steady‐state (both in solid state and solution), time‐resolved, and broadband femtosecond transient absorption spectroscopies reveal the excited‐state exciton dynamics of the two COFs, explaining the dramatic differences in their photoluminescence behaviors. Further, density functional theory (DFT) studies are performed, which confirm the occurrence of charge transfer in these systems. A direct impact of the single atom variation is also observed during I₂adsorption studies. Taken together, this study presents new routes to fabricate COFs with distinct properties by making single‐atom modulations, and widens the scope of developing emissive COFs capable of demonstrating excited‐state charge transfer, with potential applications in optoelectronics and environmental remediation. 

To gain a better understanding of the processes with which metal–organic frameworks (MOFs) self-assemble, we construct a coarse-grained simulation toolkit to model the growth of a wide variety of MOF structure types. 

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.