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Abstract Exceeding the energy density of lithium−carbon monofluoride (Li−CF_x), today's leading Li primary battery, requires an increase in fluorine content (x) that determines the theoretical capacity available from C−F bond reduction. However, high F‐content carbon materials face challenges such as poor electronic conductivity, low reduction potentials (<1.3 V versus Li/Li⁺), and/or low C−F bond utilization. This study investigates molecular structural design principles for a new class of high F‐content fluoroalkyl‐aromatic catholytes that address these challenges. A polarizable conjugated system—an aromatic ring with an alkene linker—functions as electron acceptor and redox initiator, enabling a cascade defluorination of an adjacent perfluoroalkyl chain (R_F= −C_nF_2n+1). The synthesized molecules successfully overcome premature deactivation observed in previously studied catholytes and achieve close‐to‐full defluorination (up to 15/17 available F), yielding high gravimetric capacities of 748 mAh g⁻¹_{fluoroalkyl‐aromatic}and energies of 1785 Wh kg⁻¹_{fluoroalkyl‐aromatic}. The voltage compatibility between fluoroalkyl‐aromatics and CF_xenables design of hybrid cells containing C−F redox activity in both solid and liquid phases, with a projected enhancement of Li–CF_xgravimetric energy by 35% based on weight of electrodes+electrolyte. With further improvement of cathode architecture, these “liquid CF_x” analogues are strong candidates for exceeding the energy limitations of today's primary chemistries. 

Asymmetric hollow fibers were spun with either an internal or external skin layer for an emerging class of microporous polymers using a dry jet, wet quench extrusion technique. The poly(arylene ether) (PAE) used for spinning contains free volume promoting spirobifluorene (SBF) and tert-Bu-triptycene (TBTrip) units in the backbone, providing benefits to penetrant size sieving and solution processability in accessible solvents relevant for commercial-scale manufacturing. However, microporous polymers often suffer from poor spinnability, and relatively high amounts of volatile solvents such as tetrahydrofuran (THF) are required to promote external skin layer formation. Therefore, an alternate spinning technique was developed that required no volatile solvents and resulted in a defect-free internal skin layer for low-pressure applications. Dope solution compositions and ternary phase diagrams for the polymer, SBF-TBTrip-I, are also reported, along with details on fiber morphology. Regardless of the spinning technique used, the SBF-TBTrip-I fibers exhibited desirable gas transport properties with O2/N2 and CO2/CH4 selectivities comparable to those of dense films and H2-based selectivities occasionally surpassing those of dense films. By forming thin selective layers, permeances for all gases tested were significantly higher than those of comparable thick films. This work presents an early attempt to manufacture this emerging class of polymers into industrially relevant hollow fiber membrane geometries while providing useful insights into the unique challenges of spinning microporous polymers. 

The design of flow reactors for heterogeneous photocatalysis is key to enhancing the control, efficiency, and scalability of chemical reactions. However, conventional designs such as slurry reactors and fixed bed reactors often suffer from poor light penetration, challenging catalyst attachment to the support, and difficult separations. We report an efficient and robust methodology for the functionalization of perfluoroalkoxy (PFA) coil reactors with different fluorinated photocatalysts [a perylene diimide (F-PDI) and poly(p-phenylene ethynylene) polymers (PPEST and POLPDI)] through fluorophilic interactions. We have evaluated the efficiency of photocatalyst-functionalized coil reactors in continuous flow experiments through the [2 + 2] photocycloaddition of 9-vinylcarbazole (VCZ) using blue and green light (440 and 525 nm). The conversion of VCZ to the product 1,2-trans-dicarbazylcyclobutane (t-DCZCB) was continuously monitored by in-line nuclear magnetic resonance (NMR) spectroscopy, and we found that PPEST was the most robust photocatalyst coating of those studied, leading to high conversions with different lamp powers and residence times. Further experiments proved that PPEST-functionalized coil reactors were stable and efficient after 18 h of continuous flow with conversions from around 50 to 75%. 

Easily tunable and processable, porous organic polymers (POPs) have found increasing utility in various applications. Molecular modeling and simulations are invaluable tools in polymer science but remain under-reported in the POP literature. Accurate modeling and simulation of these materials could boost the discovery of high-performance POPs and allow for a more thorough contribution to big data. These polymers contain free volume-promoting structural units, such as iptycenes, and exhibit high glass-transition temperatures, excellent thermal stability, and tunable functionality. However, popular transferable force fields utilized in allatomistic molecular dynamics (MD) simulations are not fully parametrized for intrinsically porous thermoplastic materials. We present a streamlined workflow for all-atomistic MD simulations of nonporous and porous amorphous polymer materials. In conjunction with the programs ORCA, Q-Force, Assemble!, and GROMACS, a highly accessible methodology is established for force field (FF) parametrization, creation of initial configurations, and simulation of various nonporous and porous polymers. This protocol can reproduce experimental bulk densities and fractional free volume values for amorphous polymeric materials with excellent accuracy and has been made available as a Python package, called PolyPal. As an example, we present our results using PolyPal on a series of nonporous and porous polymers that were previously synthesized and experimentally characterized. FF accuracy was also validated through solid-state NMR studies. These simulations will not only open new avenues for the rational design of high-performance POPs through the contribution of improved insight but also provide a streamlined pathway for simulating previously unexplored porous polymeric materials. 

H₂S/CH₄and CO₂/CH₄separations show opposing trends, making simultaneous improvement challenging. This is addressed by increasing free volume to enhance competitive sorption effects and boosting diffusion selectivity throughin situcrosslinking.