Single-Crystalline Imine-Linked Two-Dimensional Covalent Organic Frameworks Separate Benzene and Cyclohexane Efficiently

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(43), С. 19813 - 19824

Опубликована: Окт. 20, 2022

Two-dimensional (2D) covalent organic frameworks (COFs) are composed of structurally precise, permanently porous, layered macromolecular sheets, which traditionally synthesized as polycrystalline solids with crystalline domain lengths smaller than 100 nm. Here, we polymerize imine-linked 2D COFs suspensions faceted single crystals in little 5 min at moderate temperature and ambient pressure. Single two were prepared, consisting a rhombic COF (TAPPy-PDA) hexagonal (TAPB-DMPDA). The sizes TAPPy-PDA TAPB-DMPDA tuned from 720 nm to 4 μm 450 20 width, respectively. High-resolution transmission electron microscopy revealed that the consist layered, polymers comprising single-crystalline domains. Continuous rotation diffraction resolved unit cell crystal structure both COFs, a-b plane but disordered stacking c dimension. incorporated into gas chromatography separation columns exhibited unusual selective retention cyclohexane over benzene, significantly outperforming TAPB-DMPDA. Polycrystalline no separation, while poor opposite order elution, retaining benzene more cyclohexane, indicating importance improved material quality for exhibit properties derive their structures. This work represents first example synthesizing pressure short reaction times demonstrates promise high-quality molecular separations.

Язык: Английский

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The order–disorder conundrum: a trade-off between crystalline and amorphous porous organic polymers for task-specific applications

Journal of Materials Chemistry A, Год журнала: 2022, Номер 10(33), С. 17077 - 17121

Опубликована: Янв. 1, 2022

The review unravels the order–disorder conundrum in porous organic polymers view of task-specific applications through a comparative deliberation.

Язык: Английский

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Exceptionally high charge mobility in phthalocyanine-based poly(benzimidazobenzophenanthroline)-ladder-type two-dimensional conjugated polymers

Nature Materials, Год журнала: 2023, Номер 22(7), С. 880 - 887

Опубликована: Июнь 19, 2023

Abstract Two-dimensional conjugated polymers (2DCPs), composed of multiple strands linear with extended in-plane π-conjugation, are emerging crystalline semiconducting for organic (opto)electronics. They represented by two-dimensional π-conjugated covalent frameworks, which typically suffer from poor π-conjugation and thus low charge carrier mobilities. Here we overcome this limitation demonstrating two phthalocyanine-based poly(benzimidazobenzophenanthroline)-ladder-type 2DCPs (2DCP-MPc, M = Cu or Ni), constructed octaaminophthalocyaninato metal( ii ) naphthalenetetracarboxylic dianhydride polycondensation under solvothermal conditions. The 2DCP-MPcs exhibit optical bandgaps ~1.3 eV highly delocalized π-electrons. Density functional theory calculations unveil strongly dispersive energy bands small electron–hole reduced effective masses ~0.15 m 0 the layer-stacked 2DCP-MPcs. Terahertz spectroscopy reveals band transport Drude-type free carriers in exceptionally high sum mobility electrons holes ~970 cm 2 V −1 s at room temperature, surpassing that reported 2DCPs. This work highlights critical role conjugation enhancing properties great potential high-mobility future

Язык: Английский

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Two‐Dimensional Covalent Organic Framework Membranes for Liquid‐Phase Molecular Separations: State of the Field, Common Pitfalls, and Future Opportunities

Advanced Materials, Год журнала: 2023, Номер 36(1)

Опубликована: Апрель 4, 2023

Abstract 2D covalent organic frameworks (2D COFs) are attractive candidates for next‐generation membranes due to their robust linkages and uniform, tunable pores. Many publications have claimed achieve selective molecular transport through COF pores, but reported performance metrics similar networks vary dramatically, in several cases the experiments inadequate support such conclusions. These issues require a reevaluation of literature. Published examples liquid‐phase separations can be broadly divided into two categories, each with common characteristics: polycrystalline films (most >1 µm thick) weakly crystalline or amorphous <500 nm thick). Neither category has demonstrated consistent relationships between designed pore structure separation performance, suggesting that these imperfect materials do not sieve molecules uniform In this perspective, rigorous practices evaluating membrane structures described, which will facilitate development toward molecularly precise capable performing previously unrealized chemical separations. absence more standard proof, reports COF‐based should treated skepticism. As methods control polymerization improve, polymer may exhibit exquisite energy efficient relevant contemporary challenges.

Язык: Английский

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Outstanding Humidity Chemiresistors Based on Imine-Linked Covalent Organic Framework Films for Human Respiration Monitoring

Nano-Micro Letters, Год журнала: 2023, Номер 15(1)

Опубликована: Июнь 7, 2023

Human metabolite moisture detection is important in health monitoring and non-invasive diagnosis. However, ultra-sensitive quantitative extraction of respiration information real-time remains a great challenge. Herein, chemiresistors based on imine-linked covalent organic framework (COF) films with dual-active sites are fabricated to address this issue, which demonstrates an amplified humidity-sensing signal performance. By regulation monomers functional groups, these COF can be pre-engineered achieve high response, wide range, fast recovery time. Under the condition relative humidity ranging from 13 98%, COFTAPB-DHTA film-based sensor exhibits outstanding sensing performance expanded response value 390 times. Furthermore, values highly linear range below 60%, reflecting mechanism at molecular level. Based dual-site adsorption (-C=N-) (C-N) stretching vibrations, reversible tautomerism induced by hydrogen bonding water molecules demonstrated main intrinsic for effective detection. In addition, synthesized further exploited effectively detect human nasal oral breathing as well fabric permeability, will inspire novel designs humidity-detection devices.

Язык: Английский

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Three-dimensional covalent organic frameworks with pto and mhq-z topologies based on Tri- and tetratopic linkers

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Май 19, 2023

Three-dimensional (3D) covalent organic frameworks (COFs) possess higher surface areas, more abundant pore channels, and lower density compared to their two-dimensional counterparts which makes the development of 3D COFs interesting from a fundamental practical point view. However, construction highly crystalline COF remains challenging. At same time, choice topologies in is limited by crystallization problem, lack availability suitable building blocks with appropriate reactivity symmetries, difficulties structure determination. Herein, we report two pto mhq-z designed rationally selecting rectangular-planar trigonal-planar conformational strains. The show large size 46 Å an extremely low calculated density. net topology solely constructed totally face-enclosed polyhedra displaying precise uniform micropore 1.0 nm. high CO2 adsorption capacity at room temperature can potentially serve as promising carbon capture adsorbents. This work expands accessible topologies, enriching structural versatility COFs.

Язык: Английский

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Aromatic Amine-Functionalized Covalent Organic Frameworks (COFs) for CO₂/N₂ Separation

ACS Applied Materials & Interfaces, Год журнала: 2023, Номер 15(4), С. 5118 - 5127

Опубликована: Янв. 17, 2023

CO2 is a prominent example for an exhaust gas, and it known its high impact on global warming. Therefore, carbon capture from emissions of industrial processes increasingly important to halt prevent the disruptive consequences Covalent organic frameworks (COFs) as porous nanomaterials have been shown selectively adsorb in quantities with CO2/N2 selectivity. Interactions amines are recognized help emissions. Herein, novel COF (Me3TFB-(NH2)2BD), which was not accessible via direct condensation reaction, synthetized by dynamic linker exchange starting Me3TFB-BD. Despite exchange, porosity largely maintained, resulting BET surface area 1624 ± 89 m2/g. The N2 adsorption isotherms at 273 295 K were studied determine performance flue gas conditions. Me3TFB-(NH2)2BD adsorbs 1.12 0.26 0.72 0.07 mmol/g 1 bar K, respectively. shows IAST selectivity under conditions (273 K:83 11, K: 47 11). interaction aromatic amine groups based physisorption, expected make regeneration material energy efficient.

Язык: Английский

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Beyond Solvothermal: Alternative Synthetic Methods for Covalent Organic Frameworks

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(37)

Опубликована: Июнь 2, 2023

Abstract Covalent organic frameworks (COFs) are crystalline porous materials that hold a wealth of potential applications across various fields. The development COFs, however, is significantly impeded by the dearth efficient synthetic methods. traditional solvothermal approach, while prevalent, fraught with challenges such as complicated processes, excessive energy consumption, long reaction times, and limited scalability, rendering it unsuitable for practical applications. quest simpler, quicker, more energy‐efficient, environmentally benign strategies thus paramount bridging gap between academic COF chemistry industrial application. This Review provides an overview recent advances in alternative methods, particular emphasis on input. We discuss representative examples synthesis facilitated microwave, ultrasound, mechanic force, light, plasma, electric field, electron beam. Perspectives advantages limitations these methods against approach highlighted.

Язык: Английский

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Constructing Photocatalytic Covalent Organic Frameworks with Aliphatic Linkers

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(29), С. 20107 - 20115

Опубликована: Июнь 6, 2024

Photocatalytic covalent organic frameworks (COFs) are typically constructed with rigid aromatic linkers for crystallinity and extended π-conjugation. However, the essential hydrophobicity of backbone can limit their performances in water-based photocatalytic reactions. Here, we first time report synthesis hydrophilic COFs aliphatic [tartaric acid dihydrazide (TAH) butanedioic dihydrazide] that function as efficient photocatalysts H

Язык: Английский

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Designing Organic Material Electrodes for Lithium-Ion Batteries: Progress, Challenges, and Perspectives

Electrochemical Energy Reviews, Год журнала: 2024, Номер 7(1)

Опубликована: Апрель 11, 2024

Язык: Английский

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