Covalent Organic Frameworks: Design, Synthesis, and Functions

Chemical Reviews, Год журнала: 2020, Номер 120(16), С. 8814 - 8933

Опубликована: Янв. 22, 2020

Covalent organic frameworks (COFs) are a class of crystalline porous polymers with permanent porosity and highly ordered structures. Unlike other polymers, significant feature COFs is that they structurally predesignable, synthetically controllable, functionally manageable. In principle, the topological design diagram offers geometric guidance for structural tiling extended polygons, polycondensation reactions provide synthetic ways to construct predesigned primary high-order Progress over past decade in chemistry these two aspects undoubtedly established base COF field. By virtue availability units diversity topologies linkages, have emerged as new field materials offer powerful molecular platform complex tailor-made functional development. Here we target comprehensive review field, historic overview survey advances topology reactions, illustrate features diversities, scrutinize development potential various functions through elucidating structure–function correlations based on interactions photons, electrons, holes, spins, ions, molecules, discuss key fundamental challenging issues need be addressed, predict future directions from chemistry, physics, perspectives.

Язык: Английский

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Post-synthetic modification of covalent organic frameworks

Chemical Society Reviews, Год журнала: 2019, Номер 48(14), С. 3903 - 3945

Опубликована: Янв. 1, 2019

This review is aimed at providing an in-depth understanding of the potential post-synthetic strategies for modification covalent organic frameworks.

Язык: Английский

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Solving the COF trilemma: towards crystalline, stable and functional covalent organic frameworks

Chemical Society Reviews, Год журнала: 2020, Номер 49(23), С. 8469 - 8500

Опубликована: Янв. 1, 2020

Covalent organic frameworks (COFs) have entered the stage as a new generation of porous polymers which stand out by virtue their crystallinity, diverse framework topologies and accessible pore systems. An important - but still underdeveloped feature COFs is potentially superior stability in comparison to other materials. Achieving are simultaneously crystalline, stable, functional challenging reversible bond formation one prime prerequisites for crystallization COFs. However, COF field matures strategies surfaced that bypass this crystallinity dichotomy. Three major approaches obtaining both stable crystalline taken form recent years: Tweaking reaction conditions linkages, separating order inducing step step, controlling structural degrees freedom during assembly final COF. This review discusses rational engineering COFs, apt at overcoming current challenges design open up avenues real-world applications

Язык: Английский

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A Scalable General Synthetic Approach toward Ultrathin Imine-Linked Two-Dimensional Covalent Organic Framework Nanosheets for Photocatalytic CO₂ Reduction

Journal of the American Chemical Society, Год журнала: 2019, Номер 141(43), С. 17431 - 17440

Опубликована: Окт. 13, 2019

Fabricating ultrathin two-dimensional (2D) covalent organic framework (COF) nanosheets (NSs) in large scale and high yield still remains a great challenge. This limits the exploration of unique functionalities wide range application potentials such materials. Herein, we develop scalable general bottom-up approach to facilely synthesize (<2.1 nm) imine-based 2D COF NSs (including COF-366 NSs, COF-367 COF-367-Co TAPB-PDA TAPB-BPDA NSs) (>100 mg) (>55%), via an imine-exchange synthesis strategy through adding excess amounts 2,4,6-trimethylbenzaldehyde into reaction system under solvothermal conditions. Impressively, visualization periodic pore lattice for by scanning tunneling microscope (STM) clearly discloses nature. In particular, isolated are subject heterogeneous photocatalyst CO2-to-CO conversion, showing excellent efficiency with CO production rate as 10 162 μmol g-1 h-1 selectivity ca. 78% aqueous media visible-light irradiation, far superior corresponding bulk materials comparable thus reported state-of-the-art driven heterocatalysts.

Язык: Английский

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Optoelectronic processes in covalent organic frameworks

Chemical Society Reviews, Год журнала: 2020, Номер 50(3), С. 1813 - 1845

Опубликована: Дек. 17, 2020

Covalent organic frameworks (COFs) are crystalline porous materials constructed from molecular building blocks using diverse linkage chemistries. Their modular construction system allows not only for tailor-made design but also an immense variety of blocks, opening the door to numerous different functionalities and potential applications. As a consequence, large number that can act as light-harvesters, semiconductors, ligands, binding sites or redox centers have recently been integrated into scaffolds COFs. This unique combination reticular chemistry with control intrinsic properties paves way towards new semiconducting (opto-)electronic applications such sensors, photocatalysts -electrodes, supercapacitor battery materials, solar-harvesting devices light emitting diodes. With developments regarding motif, highly stable still tunable COFs developed even under harsh conditions. Further, stacking modes distances in investigated powerful means optical electrical characteristics these self-assembled frameworks. Advanced understanding optoelectronic processes has enabled their implementation promising real-world review highlights key concepts synthesis electro- photoactive well our frameworks, hence establishing paradigm rational well-defined novel devices.

Язык: Английский

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Recent development of covalent organic frameworks (COFs): synthesis and catalytic (organic-electro-photo) applications

Materials Horizons, Год журнала: 2019, Номер 7(2), С. 411 - 454

Опубликована: Сен. 16, 2019

The review focuses on recent developments in the synthetic methodologies of COFs and their applications field organocatalysis, electrocatalysis photocatalysis. Future scope are also described.

Язык: Английский

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Metal–Covalent Organic Frameworks (MCOFs): A Bridge Between Metal–Organic Frameworks and Covalent Organic Frameworks

Angewandte Chemie International Edition, Год журнала: 2020, Номер 59(33), С. 13722 - 13733

Опубликована: Апрель 9, 2020

Abstract Many sophisticated chemical and physical properties of porous materials strongly rely on the presence metal ions within structures. Whereas homogeneous distribution metals is conveniently realized in metal–organic frameworks (MOFs), limited stability potentially restricts their practical implementation. From that perspective, development metal–covalent organic (MCOFs) may address these shortcomings by incorporating active species atop highly stable COF backbones. This Minireview highlights examples MCOFs tackle important issues from design, synthesis, characterization to cutting‐edge applications.

Язык: Английский

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Chiral covalent organic frameworks: design, synthesis and property

Chemical Society Reviews, Год журнала: 2020, Номер 49(17), С. 6248 - 6272

Опубликована: Янв. 1, 2020

Owing to the unique structural features and facile tunability of subcomponents channels, chiral COFs show great potential in heterogeneous catalysis, enantioselective separation, recognition.

Язык: Английский

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Chiral BINOL-Based Covalent Organic Frameworks for Enantioselective Sensing

Journal of the American Chemical Society, Год журнала: 2019, Номер 141(17), С. 7081 - 7089

Опубликована: Апрель 11, 2019

Covalent organic frameworks (COFs) have emerged as a novel platform for material design and functional explorations, but it remains challenge to synthetically functionalize targeted structures task-specific applications. Optically pure 1,1′-bi-2-naphthol (BINOL) is one of the most important sources chirality synthesis materials science, has not yet been used in construction COFs enantioselective processes. Here, by elaborately designing choosing an enantiopure BINOL-based linear dialdehyde tris(4-aminophenyl)benzene derivative or tetrakis(4-aminophenyl)ethene building blocks, two imine-linked chiral fluorescent with 2D layered hexagonal tetragonal structure are prepared. The COF containing flexible tetraphenylethylene units can be readily exfoliated into ultrathin nanosheets electrospun make free-standing nanofiber membrane. In both solution membrane systems, fluorescence effectively quenched odor vapors via supramolecular interactions immobilized BINOL moieties, leading remarkable vapor sensors. Compared homogeneous exhibited greatly enhanced sensitivity enantioselectivity owing confinement effect conformational rigidity sensing groups framework. ability place such useful auxiliary inside open channels capable amplifying discrimination analytes represents major step toward rational porous molecular more

Язык: Английский

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Laminated self-standing covalent organic framework membrane with uniformly distributed subnanopores for ionic and molecular sieving

Nature Communications, Год журнала: 2020, Номер 11(1)

Опубликована: Янв. 30, 2020

Abstract The preparation of subnanoporous covalent-organic-framework (COF) membranes with high performance for ion/molecule sieving still remains a great challenge. In addition to the difficulties in fabricating large-area COF membranes, main reason is that pore size 2D COFs much larger than most gas molecules and/or ions. It urgently required further narrow their sizes meet different separation demands. Herein, we report simple and scalable way grow large-area, pliable, free-standing via one-step route at organic–organic interface. can be adjusted from >1 nm sub-nm scale by changing stacking mode layers AA AB stacking. obtained membrane composed highly-ordered nanoflakes demonstrated have aperture (∼0.6 nm), uniform distribution shows good potential organic solvent nanofiltration, water treatment separation.

Язык: Английский

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