Construction of Thiadiazole-Bridged sp²-Carbon-Conjugated Covalent Organic Frameworks with Diminished Excitation Binding Energy Toward Superior Photocatalysis

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(2), С. 1318 - 1325

Опубликована: Янв. 5, 2024

Sp2-carbon-conjugated covalent organic frameworks (sp2c-COFs) have emerged as promising platforms for phototo–chemical energy conversion due to their tailorable optoelectronic properties, in-plane π-conjugations, and robust structures. However, the development of sp2c-COFs in photocatalysis is still highly hindered by limited linkage chemistry. Herein, we report a novel thiadiazole-bridged sp2c-COF (sp2c-COF-ST) synthesized thiadiazole-mediated aldol-type polycondensation. The resultant sp2c-COF-ST demonstrates high chemical stability under strong acids bases (12 M HCl or 12 NaOH). electro-deficient thiadiazole together with fully conjugated planar skeleton endows superior photoelectrochemical performance charge-carrier separation migration ability. As result, when employed photocathode, exhibits significant photocurrent up ∼14.5 μA cm–2 at 0.3 V vs reversible hydrogen electrode (RHE) visible-light irradiation (>420 nm), which much higher than those analogous COFs partial imine linkages (mix-COF-SNT ∼ 9.5 cm–2) full (imi-COF-SNNT 4.9 cm–2), emphasizing importance structure–property relationships. Further temperature-dependent photoluminescence spectra density functional theory calculations demonstrate that has smaller exciton binding well effective mass comparison mix-COF-SNT imi-COF-SNNT, suggests sp2c-conjugated enhances dissociation carrier light irradiation. This work highlights design preparation photocatalytic performance.

Язык: Английский

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Rechargeable Metal-Sulfur Batteries: Key Materials to Mechanisms

Chemical Reviews, Год журнала: 2024, Номер 124(8), С. 4935 - 5118

Опубликована: Апрель 10, 2024

Rechargeable metal-sulfur batteries are considered promising candidates for energy storage due to their high density along with natural abundance and low cost of raw materials. However, they could not yet be practically implemented several key challenges: (i) poor conductivity sulfur the discharge product metal sulfide, causing sluggish redox kinetics, (ii) polysulfide shuttling, (iii) parasitic side reactions between electrolyte anode. To overcome these obstacles, numerous strategies have been explored, including modifications cathode, anode, electrolyte, binder. In this review, fundamental principles challenges first discussed. Second, latest research on is presented discussed, covering material design, synthesis methods, electrochemical performances. Third, emerging advanced characterization techniques that reveal working mechanisms highlighted. Finally, possible future directions practical applications This comprehensive review aims provide experimental theoretical guidance designing understanding intricacies batteries; thus, it can illuminate pathways progressing high-energy-density battery systems.

Язык: Английский

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3D Crown Ether Covalent Organic Framework as Interphase Layer toward High‐Performance Lithium Metal Batteries

Advanced Materials, Год журнала: 2024, Номер 36(21)

Опубликована: Фев. 10, 2024

Abstract The practical application of lithium (Li) metal batteries is inhibited by accumulative Li dendrites and continuous active consumption during cycling, which results in a low Coulombic efficiency short lifetime. Constructing artificial solid‐electrolyte interphase (SEI) layer anode, such as 2D covalent organic frameworks (COFs), an effective strategy to restrain the formation improve cycling performance. However, exploration 3D COFs protecting layers rarely reported, because preconception that interconnect pores eventually cause disordered direction. crown ether‐based COF with ffc topology layer, ether units are arranged parallel vertical orientation along electrode, demonstrated. strong coupling effect between + accelerates diffusion kinetics enables homogeneous flux, resulting high transference number 0.85 smooth deposition Li/COF‐Cu cells display lower Li‐nucleation overpotential (17.4 mV) average ≈98.6% 340 cycles incorporation. This work gives new insight into designing for energy storage systems.

Язык: Английский

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Lithiophilic Covalent Organic Framework as Anode Coating for High‐Performance Lithium Metal Batteries

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(11)

Опубликована: Янв. 16, 2024

Abstract The growth of disorganized lithium dendrites and weak solid electrolyte interphase greatly impede the practical application metal batteries. Herein, we designed synthesized a new kind stable polyimide covalent organic frameworks (COFs), which have high density well‐aligned lithiophilic quinoxaline phthalimide units anchored within uniform one‐dimensional channels. COFs can serve as an artificial on anode, effectively guiding deposition ions inhibiting dendrites. unsymmetrical Li||COF−Cu battery exhibits Coulombic efficiency 99 % at current 0.5 mA cm −2 , be well retained up to 400 cycles. Meanwhile, Li‐COF||LFP full cell shows over charge 0.3 C. And its capacity maintained 91 even after 150 Therefore, significant electrochemical cycling stability illustrates feasibility employing in solving disordered

Язык: Английский

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Three-dimensional covalent organic frameworks with nia nets for efficient separation of benzene/cyclohexane mixtures

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Янв. 27, 2024

Abstract The synthesis of three-dimensional covalent organic frameworks with highly connected building blocks presents a significant challenge. In this study, we report two 3D COFs the nia topology, named JUC-641 and JUC-642, by introducing planar hexagonal triangular prism nodes. Notably, our adsorption studies breakthrough experiments reveal that both exhibit exceptional separation capabilities, surpassing previously reported most porous polymers, factor up to 2.02 for benzene cyclohexane. Additionally, dispersion-corrected density functional theory analysis suggests good performance these can be attributed incorporation aromatic presence extensive pore structures. Consequently, research not only expands diversity but also highlights potential COF materials as promising candidates environmentally-friendly applications.

Язык: Английский

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Stepwise Protonation of Three‐Dimensional Covalent Organic Frameworks for Enhancing Hydrogen Peroxide Photosynthesis

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(30)

Опубликована: Май 13, 2024

Abstract Three‐dimensional covalent organic frameworks (3D COFs), recognized for their tailorable structures and accessible active sites, offer a promising platform developing advanced photocatalysts. However, the difficulty in synthesis functionalization of 3D COFs hinders further development. In this study, we present series 3D‐ bcu ‐COFs with 8 connected porphyrin units linked by linear linkers through imine bonds as versatile photocatalyst design. The photoresponse was initially modulated functionalizing benzo‐thiadiazole or benzo‐selenadiazole groups. Furthermore, taking advantage well‐exposed sites ‐COFs, photocatalytic activity optimized stepwise protonation centers. dual protonated COF groups exhibited enhanced charge separation, leading to an increased H 2 O production under visible light. This enhancement demonstrates combined benefits linker on efficiency.

Язык: Английский

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12 Connecting Sites Linked Three‐dimensional Covalent Organic Frameworks with Intrinsic Non‐interpenetrated shp Topology for Photocatalytic H₂O₂ Synthesis

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(15)

Опубликована: Фев. 9, 2024

Developing high connectivity (>8) three-dimensional (3D) covalent organic frameworks (COFs) towards new topologies and functions remains a great challenge owing to the difficulty in getting building blocks. This however represents most important step promoting diversity of COFs due still limited dynamic bonds available for constructing at this stage. Herein, highly connected phthalocyanine-based (Pc-based) 3D MPc-THHI-COFs (M=H

Язык: Английский

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Unprecedented POSS‐Linked 3D Covalent Organic Frameworks with 2‐Fold Interpenetrated scu or sqc Topology Regulated by Porphyrin Center for Photocatalytic CO₂ Reduction

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(26)

Опубликована: Апрель 15, 2024

Abstract The synthesis and characterization of porphyrin center regulated three‐dimensional covalent organic frameworks (COFs) with 2‐fold interpenetrated scu or sqc topology have been investigated. These COFs exhibit unique structural features properties, making them promising candidates for photocatalytic applications in CO 2 reduction artemisinin synthesis. serves as an anchor metal ions, allowing precise control over structures functions the frameworks. Furthermore, coordination within framework imparts desirable catalytic enabling their potential use reactions. Overall, these metal‐controlled offer exciting opportunities development advanced materials tailored functionalities.

Язык: Английский

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Ethynyl‐Linked Donor–Acceptor Covalent Organic Framework for Highly Efficient Photocatalytic H₂O₂ Production

Advanced Energy Materials, Год журнала: 2025, Номер unknown

Опубликована: Янв. 19, 2025

Abstract Photocatalytic H 2 O synthesis from and is considered to be one of the most promising alternative approaches for manufacturing . Developing highly active selective photocatalysts significant in achieving efficient photosynthesis. Herein, an ethynyl‐linked donor–acceptor covalent organic framework (COF), named EBBT‐COF, prepared condensation reaction between electron‐deficient unit 4,4′,4″‐(1,3,5‐benzenetriyltri‐2,1‐ethynediyl)tris‐benzenamine electron‐rich benzo[1,2‐b:3,4‐b′:5,6‐b″]trithiophene‐2,5,8‐tricarboxaldehyde. Powder X‐ray diffraction N adsorption isotherm unveil crystalline porous hcb network EBBT‐COF with pores size centered at ca 2.3 nm. Spectroscopic characterizations demonstrate excellent visible‐light absorption capacity enhanced photo‐induced charge separation transport efficiency owing its architecture. Density functional theory calculations electrochemical tests indicate high activity selectivity toward 2e − reduction water oxidation triethynylbenzene trithiophene moieties accelerate ‐to‐H O‐to‐H conversion, respectively. These merits enable a photocatalyst generation yield rate 5 686 µmol g −1 h , optimal apparent quantum 15.14%, solar‐to‐chemical conversion 1.17% (λ > 400 nm), representing best performance among COF‐based reported thus far.

Язык: Английский

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Single-Crystal Three-Dimensional Covalent Organic Framework Constructed from 6-Connected Triangular Prism Node

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(41), С. 22329 - 22334

Опубликована: Окт. 4, 2023

The limited structural diversity of three-dimensional covalent organic frameworks (3D COFs) greatly restricts their application exploration. Therefore, there is an urgent need to expand library molecular building blocks, such as the development highly connected (>4 reaction sites) polyhedral nodes. Herein, by precisely controlling precursor conformation, we rationally designed a new 6-connected triangular prism node derived from triphenylbenzene molecule and further used it construct novel 3D COF (3D-TMTAPB-COF) via imine condensation reaction. Surprisingly, without addition competing reagents, 3D-TMTAPB-COF crystallized directly into single crystals ∼15 μm in size was determined adopt rare 6-fold interpenetrated (Class IIIa interpenetration) acs topology. In addition, showed high SF6 adsorption capacity (60.9 cm3 g-1) good SF6/N2 selectivity (335) at 298 K 1 bar, superior those most crystalline porous materials. This work not only confirms possibility growing large-size single-crystal COFs formed with strong bonds solvothermal method absence modulators, but also reports for future construction interesting applications.

Язык: Английский

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