Dual donor-acceptor covalent organic frameworks for hydrogen peroxide photosynthesis

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Aug. 28, 2023

Constructing photocatalytically active and stable covalent organic frameworks containing both oxidative reductive reaction centers remain a challenge. In this study, benzotrithiophene-based with spatially separated redox are rationally designed for the photocatalytic production of hydrogen peroxide from water oxygen without sacrificial agents. The triazine-containing framework demonstrates high selectivity H2O2 photogeneration, yield rate 2111 μM h-1 (21.11 μmol 1407 g-1 h-1) solar-to-chemical conversion efficiency 0.296%. Codirectional charge transfer large energetic differences between linkages linkers verified in double donor-acceptor structures periodic frameworks. sites mainly concentrated on electron-acceptor fragments near imine bond, which regulate electron distribution adjacent carbon atoms to optimally reduce Gibbs free energy O2* OOH* intermediates during formation H2O2.

Language: Английский

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Oligo(phenylenevinylene)‐Based Covalent Organic Frameworks with Kagome Lattice for Boosting Photocatalytic Hydrogen Evolution

Advanced Materials, Journal Year: 2023, Volume and Issue: 36(1)

Published: Oct. 2, 2023

Covalent organic frameworks (COFs) have shown great advantages as photocatalysts for hydrogen evolution. However, the effect of linkage geometry and type on extent π-electron conjugation in plane framework photocatalytic properties COFs remains a significant challenge. Herein, two Kagome (kgm) topologic oligo(phenylenevinylene)-based are designed synthesized boosting evolution via "two one" strategy. Under visible light irradiation, COF-954 with 5 wt% Pt cocatalyst exhibits high rate (HER) 137.23 mmol g

Language: Английский

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Regulating the H₂O₂ Photosynthetic Activity of Covalent Organic Frameworks through Linkage Orientation

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(7), P. 4728 - 4737

Published: March 13, 2024

Imine-linked isomeric covalent organic frameworks (COFs) with opposite linkage orientations are not rare, but their structure and photocatalytic property corrections still puzzling, let alone the emerging photosynthetic H2O2 performance. Herein, a pair of COFs (TB-COF TA-COF) reversed imine linkages was fabricated. Compared to TA-COF, TB-COF exhibited larger dipole moments better charge carrier separation efficiency, resulting in superior photosynthesis capability via dominant oxygen reduction reaction (ORR) paths (O2–O2•––H2O2 O2–O2•––O21–H2O2) feeble water oxidation (WOR) paths. With no sacrificial agents air, rates were 5186 μmol g–1 h–1 4111 natural seawater, respectively. The seawater-produced can be directly utilized for tetracycline degradation, manifesting big picture wastewater treatment by H2O2. Theoretical calculations revealed that hydroxyl-rich benzene ring photooxidation part triazine unit primary photoreduction part. Through linkage-orientation regulation, electronic structures, migration property, energy barrier rate determination step 2e– ORR WOR well-modulated. current work provides insight into effect orientation on performance may enlighten design catalysts photosynthesis.

Language: Английский

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Ionic Covalent Organic Frameworks in Adsorption and Catalysis

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(22)

Published: April 2, 2024

The ion extraction and electro/photo catalysis are promising methods to address environmental energy issues. Covalent organic frameworks (COFs) a class of template construct absorbents catalysts because their stable frameworks, high surface areas, controllable pore environments, well-defined catalytic sites. Among them, ionic COFs as unique crystalline porous materials, with charges in the or along walls, have shown different properties resulting performance these applications those from charge-neutral COFs. In this review, current research progress based on for conversion, including cationic/anionic materials is reviewed terms synthesis strategy, modification methods, mechanisms adsorption catalysis, well applications. Finally, we demonstrated challenges future development design strategies

Language: Английский

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A nonfullerene acceptor as a solid additive realizing a record efficiency of 17.74% in quasi-layered all-polymer solar cells

Journal of Materials Chemistry A, Journal Year: 2024, Volume and Issue: 12(7), P. 4077 - 4085

Published: Jan. 1, 2024

The nonfullerene acceptor L8-BO as solid additive was incorporated into QLA-PSCs based on PM6 and PY-IT. molecular orientation exciton diffusion length in PY-IT layer can be optimized, resulting the PCE enhanced from 16.14% to 17.74%.

Language: Английский

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Protonation of an Imine‐linked Covalent Organic Framework for Efficient H₂O₂ Photosynthesis under Visible Light up to 700 nm

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(32)

Published: May 13, 2024

Abstract Covalent organic frameworks (COFs) are promising photocatalysts for H 2 O production from water via oxygen reduction reaction (ORR). The design of COFs efficient indubitably hinges on an in‐depth understanding their ORR mechanisms. In this work, taking imine‐linked COF as example, we demonstrate that protonation the functional units such imine, amine, and triazine, is a highly strategy to upgrade activity levels synthesis. not only extends light absorption but also provides proton sources directly participate in generation. Notably, simplifies pathways , i.e. indirect superoxide radical ( ) mediated route direct one‐step two‐electron route. Theoretical calculations confirm favors synthesis due easy access protons near sites removes energy barrier generating *OOH intermediate. These findings extend mechanistic insight into photosynthesis provide rational guideline upgradation COFs.

Language: Английский

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

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(30)

Published: May 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.

Language: Английский

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Covalent Organic Frameworks: Linkage Chemistry and Its Critical Role in The Evolution of π Electronic Structures and Functions

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(22)

Published: March 19, 2024

Covalent organic frameworks (COFs) provide a molecular platform for designing novel class of functional materials with well-defined structures. A crucial structural parameter is the linkage, which dictates how knot and linker units are connected to form two-dimensional polymers layer frameworks, shaping ordered π-array porous architectures. However, roles linkage in development π electronic structures functions remain fundamental yet unresolved issues. Here we report designed synthesis COFs featuring four representative linkages: hydrazone, imine, azine, C=C bonds, elucidate their impacts on evolution functions. Our observations revealed that hydrazone provides non-conjugated connection, while imine azine allow partial conjugation, bond permits full π-conjugation. Importantly, profoundly influences control functions, unraveling its pivotal role determining key properties such as band gap, frontier energy levels, light absorption, luminescence, carrier density mobility, magnetic permeability. These findings highlight significance chemistry offer general transformative guidance framework achieve

Language: Английский

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Push–pull–pull interactions of 2D imide–imine-based covalent organic framework to promote charge separation in photocatalytic hydrogen production

Journal of Materials Chemistry A, Journal Year: 2024, Volume and Issue: 12(18), P. 10790 - 10798

Published: Jan. 1, 2024

This study demonstrated the synthesis of imide–imine based COFs, boosting electrical conductivity in network due to presence dual electron-acceptor centers. makes them efficient for light-induced hydrogen evolution reactions.

Language: Английский

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Ionic Covalent Organic Frameworks in Adsorption and Catalysis

Angewandte Chemie, Journal Year: 2024, Volume and Issue: 136(22)

Published: April 2, 2024

Abstract The ion extraction and electro/photo catalysis are promising methods to address environmental energy issues. Covalent organic frameworks (COFs) a class of template construct absorbents catalysts because their stable frameworks, high surface areas, controllable pore environments, well‐defined catalytic sites. Among them, ionic COFs as unique crystalline porous materials, with charges in the or along walls, have shown different properties resulting performance these applications those from charge‐neutral COFs. In this review, current research progress based on for conversion, including cationic/anionic materials is reviewed terms synthesis strategy, modification methods, mechanisms adsorption catalysis, well applications. Finally, we demonstrated challenges future development design strategies

Language: Английский

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