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Combining high‐voltage nickel‐rich cathodes with lithium metal anodes is among the most promising approaches for achieving high‐energy‐density lithium batteries. However, most current electrolytes fail to simultaneously satisfy the compatibility requirements for the lithium metal anode and the tolerance for the ultra‐high voltage NCM811 cathode. Here, we have designed an ultra‐oxidation‐resistant electrolyte by meticulously adjusting the composition of fluorinated carbonates. Our study reveals that a solid‐electrolyte interphase (SEI) rich in LiF and Li2O is constructed on the lithium anode through the synergistic decomposition of the fluorinated solvents and PF6− anion, facilitating smooth lithium metal deposition. The superior oxidation resistance of our electrolyte enables the Li||NCM811 cell to deliver a capacity retention of 80 % after 300 cycles at an ultrahigh cut–off voltage of 4.8 V. Additionally, a pioneering 4.8 V‐class lithium metal pouch cell with an energy density of 462.2 Wh kg−1 stably cycles for 110 cycles under harsh conditions of high cathode loading (30 mg cm−2), low N/P ratio (1.18), and lean electrolytes (2.3 g Ah−1). [ABSTRACT FROM AUTHOR]

Multitopic organic linkers can provide a means to organize metal cluster nodes in a regular three-dimensional array. Herein, we show that isonicotinic acid N-oxide (HINO) serves as the linker in the formation of a metal-organic framework featuring Dy2 single-molecule magnets as nodes. Importantly, guest solvent exchange induces a reversible single-crystal to single-crystal transformation between the phases Dy2(INO)4(NO3)2⋅2 solvent (solvent=DMF (Dy2-DMF), CH3CN (Dy2-CH3CN)), thereby switching the effective magnetic relaxation barrier (determined by ac magnetic susceptibility measurements) between a negligible value for Dy2-DMF and 76 cm(-1) for Dy2-CH3CN. Ab initio calculations indicate that this difference arises not from a significant change in the intrinsic relaxation barrier of the Dy2 nodes, but rather from a slowing of the relaxation rate of incoherent quantum tunneling of the magnetization by two orders of magnitude.

Adsorption‐based removal of carbon dioxide (CO2) from gas mixtures has demonstrated great potential for solving energy security and environmental sustainability challenges. However, due to similar physicochemical properties between CO2 and other gases as well as the co‐adsorption behavior, the selectivity of CO2 is severely limited in currently reported CO2‐selective sorbents. To address the challenge, we create a bioinspired design strategy and report a robust, microporous metal–organic framework (MOF) with unprecedented [Mn86] nanocages. Attributed to the existence of unique enzyme‐like confined pockets, strong coordination interactions and dipole‐dipole interactions are generated for CO2 molecules, resulting in only CO2 molecules fitting in the pocket while other gas molecules are prohibited. Thus, this MOF can selectively remove CO2 from various gas mixtures and show record‐high selectivities of CO2/CH4 and CO2/N2 mixtures. Highly efficient CO2/C2H2, CO2/CH4, and CO2/N2 separations are achieved, as verified by experimental breakthrough tests. This work paves a new avenue for the fabrication of adsorbents with high CO2 selectivity and provides important guidance for designing highly effective adsorbents for gas separation. [ABSTRACT FROM AUTHOR]

Developing new materials for anhydrous proton conduction under high‐temperature conditions is significant and challenging. Herein, we create a series of highly crystalline covalent organic frameworks (COFs) via a pore engineering approach. We simultaneously engineer the pore geometry (generating concave dodecagonal nanopores) and pore surface (installing multiple functional groups such as −C=N−, −OH, −N=N− and −CF3) to improve the utilization efficiency and host–guest interaction of proton carriers, hence benefiting the enhancement of anhydrous proton conduction. Upon loading with H3PO4, COFs can realize a proton conductivity of 2.33×10−2 S cm−1 under anhydrous conditions, among the highest values of all COF materials. These materials demonstrate good stability and maintain high proton conductivity over a wide temperature range (80–160 °C). This work paves a new way for designing COFs for anhydrous proton conduction applications, which shows great potential as high‐temperature proton exchange membranes. [ABSTRACT FROM AUTHOR]

Regarding the global energy crisis, it is of profound significance to develop spontaneous power generators that harvest natural energy. Fabricating humidity‐responsive actuators that can conduct such energy transduction is of paramount importance. Herein, we incorporate covalent organic frameworks with flexible polyethylene glycol to fabricate rigid‐flexible coupled membrane actuators. This strategy significantly improves the mechanical properties and humidity‐responsive performance of the actuators, meanwhile, the existence of ordered structures enables us to unveil the actuation mechanism. These high‐performance actuators can achieve various actuation applications and exhibit interesting self‐oscillation behavior above a water surface. Finally, after being coupled with a piezoelectric film, the bilayer device can spontaneously output electricity over 2 days. This work paves a new avenue to fabricate rigid‐flexible coupled actuators for self‐sustained energy transduction. [ABSTRACT FROM AUTHOR]

It is of profound significance concerning the global energy and environmental crisis to develop new techniques that can reduce and convert CO2. To address this challenge, we built a new type of artificial photoenzymatic system for CO2 reduction, using a rationally designed mesoporous olefin‐linked covalent organic framework (COF) as the porous solid carrier for co‐immobilizing formate dehydrogenase (FDH) and Rh‐based electron mediator. By adjusting the incorporating content of the Rh electronic mediator, which facilitates the regeneration of nicotinamide cofactor (NADH) from NAD+, the apparent quantum yield can reach as high as 9.17±0.44 %, surpassing all reported NADH‐regenerated photocatalysts constructed by crystalline framework materials. Finally, the assembled photocatalyst–enzyme coupled system can selectively convert CO2 to formic acid with high efficiency and good reusability. This work demonstrates the first example using COFs to immobilize enzymes for artificial photosynthesis systems that utilize solar energy to produce value‐added chemicals. [ABSTRACT FROM AUTHOR]

Attributed to the unique topological complexity and elegant beauty, Borromean systems are attracting intense attention. However, at present, the construction of Borromean linked organic polymers remains a challenge. To address this formidable challenge, we developed a supramolecular‐synthon‐driven approach to fabricate Borromean linked organic polymer. The solvothermal condensation reaction of a judiciously selected trigonal pyramidal building block, 1,3,5‐Tris(4‐aminophenyl)adamantane, with linear dialdehyde building blocks allowed the construction of two rare covalent organic frameworks (COFs) with high crystallinity and robustness. Structure refinement unveiled the successful formation of entangled 2D→2D Borromean arrayed structures. Both the two COFs were of microporosity and thus demonstrated the potentials for gas separation. The successful synthesis of the first two Borromean linked organic polymers paves the avenue to expand the supramolecular‐synthon‐driven approach to other building blocks and topologies, and broadens the family and scope of COFs. [ABSTRACT FROM AUTHOR]

Organic polymers are usually amorphous or possess very low crystallinity. The metal complexes of organic polymeric ligands are also difficult to crystallize by traditional methods because of their poor solubilities and their 3D structures can not be determined by single-crystal X-ray crystallography owing to a lack of single crystals. Herein, we report the crystal structure of a 1D ZnII coordination polymer fused with an organic polymer ligand made in situ by a [2+2] cycloaddition reaction of a six-fold interpenetrated metal-organic framework. It is also shown that this organic polymer ligand can be depolymerized in a single-crystal-to-single-crystal (SCSC) fashion by heating. This strategy could potentially be extended to make a range of monocrystalline metal organopolymeric complexes and metal-organic organopolymeric hybrid materials. Such monocrystalline metal complexes of organic polymers have hitherto been inaccessible for materials researchers. [ABSTRACT FROM AUTHOR]

Aqueous proton batteries are attracting increasing attention in the large‐scale next‐generation energy storage field. However, the electrode materials for proton batteries often suffer from low specific capacity and unsatisfactory cycle durability. Herein, we synthesize two highly crystalline and robust polyimide covalent organic frameworks (COFs) through a solvent‐free flux synthesis approach with benzoic acid as a flux and catalyst. The as‐synthesized COFs possess enriched redox‐active sites for proton storage and intrinsic Grotthuss proton conduction, rendering them ideal candidates for proton electrode materials. The optimal COF electrodes achieve a high specific capacity of 180 mAh/g at 0.1 A/g, among the highest COF‐based proton batteries, and exhibit an outstanding rate capability of up to 100 A/g and long‐term cycling stability with capacity retention of 99 % after 5000 cycles at 5 A/g. The assembled full cells deliver a specific capacity of 150 mAh/g at 0.2 A/g with a maximum energy density of 72 Wh/kg and a maximum supercapacitor‐level power density of 64 kW/kg, surpassing all reported COF‐based systems. This work paves a new avenue for the design of electrode materials for aqueous proton batteries with high energy density, power density, rate capability and long‐term cycling stability. [ABSTRACT FROM AUTHOR]

Priority recognition separation of inert and larger ethane molecules from high‐concentration ethylene mixtures instead of the traditional thermodynamic or size sieving strategy is a fundamental challenge. Herein, we report ethane triggered gate‐opening in the flexible‐robust metal‐organic framework Zn(ad)(min), the 3‐methylisonicotinic acid ligand can spin as a flexible gate when adsorbing the cross‐section well‐matched ethane molecule, achieving an unprecedented ethane adsorption capacity (62.6 cm3 g−1) and ethane/ethylene uptake ratio (3.34) under low‐pressure region (0.1 bar and 298 K). The ethane‐induced structural transition behavior has been uncovered by a collaboration of single‐crystal X‐ray diffraction, in situ variable pressure X‐ray diffraction and theoretical calculations, elucidating the synergetic mechanism of cross‐section matching and multiple supramolecular interactions within the tailor‐made pore channels. Dynamic breakthrough experiments have revealed the outstanding separation performance of Zn(ad)(min) during the production of ultra‐high purity ethylene (>99.995 %) with a productivity of up to 39.2 L/kg under ambient conditions. [ABSTRACT FROM AUTHOR]

Solid‐state electrolytes (SSEs) with high Li‐ion transference numbers and fast ionic conductivity are urgently needed for technological innovations in lithium‐metal batteries. To promote the dissociation of ion pairs and overcome the mechanical brittleness and interface defects caused by traditional fillers in polymeric electrolytes, we designed and fabricated a cationic hypercrosslinking metal‐organic polyhedra (HCMOPs) polymer as SSE. Benefiting a three‐component synergistic effect: cationic MOPs, branched polyethyleneimine macromonomer and polyelectrolyte units, the Li‐HCMOP electrolyte possesses a high Li‐ion conductivity, a high Li‐ion transference number and a low activation energy. The LiFePO4/Li battery exhibits high capacity with superior rate performance and cycling stability. Moreover, soluble MOPs serve as high crosslinking nodes to provide excellent mechanical strength for electrolytes and good compatibility with polymers. This work highlights an effective idea of high‐performance MOP‐based solid‐state electrolytes applied in LMBs. [ABSTRACT FROM AUTHOR]

Chiral separation plays a pivotal role in both practical applications and industrial productions. However, traditional chiral stationary phases (CSPs) exhibit inherent instability in alkaline environments, presenting a significant challenge despite their importance. Herein, basophilic alcalase is creatively developed to fabricate ultrastable protein‐based CSPs that can efficiently work under alkaline conditions. An in‐depth theoretical simulation is conducted to unveil the unique three‐dimensional conformation of alcalase, showing selective affinity towards various enantiomers of chiral amino acids and drugs, especially acidic substrates. Subsequently, an in situ assembly strategy is used to immobilize alcalase within a hydrazone‐linked covalent organic framework (COF) platform. The generated protein‐based CSPs enable successful baseline separation (Rs≥1.50) for various value‐added compounds (e.g., non‐steroidal drug, RS‐flurbiprofen; nucleotide analog, RS‐tenofovir) via high‐performance liquid chromatography, surpassing the commercial chiral column. Furthermore, a systematic study reveals that increasing hydrophilicity and pore sizes of COFs can enhance the separation performance. Remarkably, the obtained CSPs demonstrated exceptional durability, maintaining performance for >2,400 runs. This study provides a new member to the protein library for CSPs, and represents an innovative and effective platform for CSPs with immense potential for the enantioseparation of acidic drugs. [ABSTRACT FROM AUTHOR]

Creating new functional materials that efficiently support noble metal catalysts is important and in high demand. Herein, we develop a self‐polycondensation flux synthesis strategy that can produce olefin‐linked covalent organic framework (COF) platforms with high crystallinity and porosity as the supports of Pd nanoparticles for electrocatalytic nitrogen reduction reaction (ENRR). A series of “two in one” monomers integrating aldehyde and methyl reactive groups are rationally designed to afford COFs with square‐shaped pores and ultrahigh chemical stability (e.g., strong acid or alkali environments for >1 month). Functionalizing Fluorine significantly boosts the hydrophobicity of fluoro‐functionalized COFs, which can inhibit the competing hydrogen evolution reaction (HER) and enhance ENRR performances. The COFs loading Pd nanoparticles show high NH3 production yields up to 90.0±2.6 μg ⋅ h−1 ⋅ mgcat.−1 and the faradaic efficiency of 44 % at −0.2 V versus reversible hydrogen electrode, the best comprehensive performance among all reported COFs. Meanwhile, the catalysts are easy to recover and recycle, as demonstrated by their use for 15 cycles and 17 hours, with good performance retention. This work not only provides a new synthesis strategy for olefin‐linked COFs, but also paves a new avenue for the design of highly efficient ENRR catalysts. [ABSTRACT FROM AUTHOR]

Developing new enzyme‐immobilization systems to stabilize their dynamic structures and meanwhile enhance their catalytic activity is of great significance but very challenging. Herein, we design and fabricate a class of robust mesoporous covalent organic frameworks (COFs) via Michael addition‐elimination reaction. It is found that highly crystalline COFs can be produced in 10 min, which is attributed to the promoting effect of the intramolecular hydrogen bond activation. The COFs rich in hydroxyl groups can be facilely post‐modified by epibromohydrin to covalently immobilize enzymes with both high loading and activity. Furthermore, we create a solar‐driven photothermal‐promoted strategy by introducing photoactive azo groups to COF carriers, which can boost the enzyme catalytic performance (lipase) with much higher conversion of various racemic substrates and chiral resolution upon solar light irradiation. The heterogeneous biocatalysts also demonstrate exceptional reusability and stability. This work provides a green and energy‐efficient approach to facilitate the scale application of enzyme‐immobilized biocatalysts. [ABSTRACT FROM AUTHOR]

It is of profound significance concerning the global energy and environmental crisis to develop new techniques that can reduce and convert CO2. To address this challenge, we built a new type of artificial photoenzymatic system for CO2 reduction, using a rationally designed mesoporous olefin‐linked covalent organic framework (COF) as the porous solid carrier for co‐immobilizing formate dehydrogenase (FDH) and Rh‐based electron mediator. By adjusting the incorporating content of the Rh electronic mediator, which facilitates the regeneration of nicotinamide cofactor (NADH) from NAD+, the apparent quantum yield can reach as high as 9.17±0.44 %, surpassing all reported NADH‐regenerated photocatalysts constructed by crystalline framework materials. Finally, the assembled photocatalyst–enzyme coupled system can selectively convert CO2 to formic acid with high efficiency and good reusability. This work demonstrates the first example using COFs to immobilize enzymes for artificial photosynthesis systems that utilize solar energy to produce value‐added chemicals. [ABSTRACT FROM AUTHOR]