Cost‐Effective,High‐Performance Porous‐Organic‐Polymer Conductors Functionalized with Sulfonic Acid Groups by Direct Postsynthetic Substitution

We demonstrate the facile microwave‐assisted synthesis of a porous organic framework 1 and the sulfonated solid ( 1S ) through postsubstitution. Remarkably, the conductivity of 1S showed an approximately 300‐fold enhancement at 30 °C as compared to that of 1 , and reached 7.72×10⁻² S cm⁻¹ at 80 °C and 90 % relative humidity. The superprotonic conductivity exceeds that observed for any conductive porous organic polymer reported to date. This material, which is cost‐effective and scalable for mass production, also revealed long‐term performance over more than 3 months without conductivity decay.     

Reduced SnO2 Porous Nanowires with a High Density of Grain Boundaries as Catalysts for Efficient Electrochemical CO2‐into‐HCOOH Conversion

Electrochemical conversion of CO₂ into energy‐dense liquids, such as formic acid, is desirable as a hydrogen carrier and a chemical feedstock. SnO_x is one of the few catalysts that reduce CO₂ into formic acid with high selectivity but at high overpotential and low current density. We show that an electrochemically reduced SnO₂ porous nanowire catalyst (Sn‐pNWs) with a high density of grain boundaries (GBs) exhibits an energy conversion efficiency of CO₂‐into‐HCOOH higher than analogous catalysts. HCOOH formation begins at lower overpotential (350 mV) and reaches a steady Faradaic efficiency of ca. 80 % at only −0.8 V vs. RHE. A comparison with commercial SnO₂ nanoparticles confirms that the improved CO₂ reduction performance of Sn‐pNWs is due to the density of GBs within the porous structure, which introduce new catalytically active sites. Produced with a scalable plasma synthesis technology, the catalysts have potential for application in the CO₂ conversion industry.     

Co‐immobilized Phosphorylated Cofactors and Enzymes as Self‐Sufficient Heterogeneous Biocatalysts for Chemical Processes

Enzyme cofactors play a major role in biocatalysis, as many enzymes require them to catalyze highly valuable reactions in organic synthesis. However, the cofactor recycling is often a hurdle to implement enzymes at the industrial level. The fabrication of heterogeneous biocatalysts co‐immobilizing phosphorylated cofactors (PLP, FAD⁺, and NAD⁺) and enzymes onto the same solid material is reported to perform chemical reactions without exogeneous addition of cofactors in aqueous media. In these self‐sufficient heterogeneous biocatalysts, the immobilized enzymes are catalytically active and the immobilized cofactors catalytically available and retained into the solid phase for several reaction cycles. Finally, we have applied a NAD⁺‐dependent heterogeneous biocatalyst to continuous flow asymmetric reduction of prochiral ketones, thus demonstrating the robustness of this approach for large scale biotransformations.     

Lithium‐Salt Mediated Synthesis of a Covalent Triazine Framework for Highly Stable Lithium Metal Batteries

A new strategy for the synthesis of a covalent triazine framework (CTF‐1) was introduced based on the cyclotrimerization reaction of 1,4‐dicyanobenzene using lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) under ionothermal conditions. LiTFSI not only served as a catalyst, but also facilitated the in situ generation and homogeneous distribution of LiF particles across the framework. The hierarchical structure resulting upon integration of CTF‐LiF onto an airlaid‐paper (AP) offered unique features for lithium metal anodes, such as lithiophilicity from CTF, interface stabilization from LiF, and sufficient lithium storage space from AP. Based on this synergistic effect, the AP‐CTF‐LiF anode exhibited stable cycling performance even at a current density of 10 mA cm^?2.     

Efficient Construction of Well‐Defined Multicompartment Porous Systems in a Modular and Chemically Orthogonal Fashion

A microfluidic assembly approach was developed for efficiently producing hydrogel spheres with reactive multidomains that can be employed as an advantageous platform to create spherical porous networks in a facile manner with well‐defined multicompartments and spatiotemporally controlled functions. This strategy allows for not only large scale fabrication of various robust hydrogel microspheres with controlled size and porosity, but also the domains embedded in hydrogel network could be introduced in a modular manner. Additionally, the number of different domains and their ratio could be widely variable on demand. More importantly, the reactive groups distributed in individual domains could be used as anchor sites to further incorporate functional units in an orthogonal fashion, leading to well‐defined multicompartment systems. The strategy provides a new and efficient route to construct well‐defined functional multicompartment systems with great flexibility and extendibility.     

Epoxy‐Functionalized Porous Organic Polymers via the Diels–Alder Cycloaddition Reaction for Atmospheric Water Capture

The synthesis of highly microporous, epoxy‐functionalized porous organic polymers (ep‐POPs) by a one‐pot, catalyst‐free Diels–Alder cycloaddition polymerization is reported. The high oxygen content of ep‐POPs offer efficient hydrogen‐bonding sites for water molecules, thus leading to high water‐uptake capacities up to 39.2–42.4 wt % under a wide temperature range of 5–45 °C, which covers the span of climatic conditions and manufacturing applications in which such materials might be used. Importantly, ep‐POPs demonstrated regeneration temperatures as low as 55 °C, as well as excellent water stability, recyclability, and high specific surface areas up to 852 m² g⁻¹.     

Oriented Two‐Dimensional Porous Organic Cage Crystals

The formation of two‐dimensional (2D) oriented porous organic cage crystals (consisting of imine‐based tetrahedral molecules) on various substrates (such as silicon wafers and glass) by solution‐processing is reported. Insight into the crystallinity, preferred orientation, and cage crystal growth was obtained by experimental and computational techniques. For the first time, structural defects in porous molecular materials were observed directly and the defect concentration could be correlated with crystal growth rate. These oriented crystals suggest potential for future applications, such as solution‐processable molecular crystalline 2D membranes for molecular separations.     

Eosin Y‐Functionalized Conjugated Organic Polymers for Visible‐Light‐Driven CO2 Reduction with H2O to CO with High Efficiency

Visible‐light‐driven photoreduction of CO₂ to energy‐rich chemicals in the presence of H₂O without any sacrifice reagent is of significance, but challenging. Herein, Eosin Y‐functionalized porous polymers (PEosinY‐N, N=1–3), with high surface areas up to 610 m² g^?1, are reported. They exhibit high activity for the photocatalytic reduction of CO₂ to CO in the presence of gaseous H₂O, without any photosensitizer or sacrifice reagent, and under visible‐light irradiation. Especially, PEosinY‐1 derived from coupling of Eosin Y with 1,4‐diethynylbenzene shows the best performance for the CO₂ photoreduction, affording CO as the sole carbonaceous product with a production rate of 33 μmol g^?1 h^?1 and a selectivity of 92 %. This work provides new insight for designing and fabricating photocatalytically active polymers with high efficiency for solar‐energy conversion.     

Mechanochemical Friedel–Crafts Alkylation—A Sustainable Pathway Towards Porous Organic Polymers

This study elucidates an innovative mechanochemical approach applying Friedel–Crafts alkylation to synthesize porous covalent triazine frameworks (CTFs). Herein, we pursue a counterintuitive approach by utilizing a rather destructive method to synthesize well‐defined materials with intrinsic porosity. Investigating a model system including carbazole as monomer and cyanuric chloride as triazine node, ball milling is shown to successfully yield porous polymers almost quantitatively. We verified the successful structure formation by an in‐depth investigation applying XPS, solid‐state NMR and FT‐IR spectroscopy. An in situ study of pressure and temperature developments inside the milling chamber in combination with two‐dimensional liquid‐state NMR spectroscopy reveals insights into the polymerization mechanism. The versatility of this mechanochemical approach is showcased by application of other monomers with different size and geometry.