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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Integrating Bifunctionality and Chemical Stability in Covalent Organic Frameworks via One-Pot Multicomponent Reactions for Solar-Driven H₂O₂ Production

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(5), P. 2975 - 2984

Published: Jan. 25, 2023

Multicomponent reactions (MCRs) can be used to introduce different functionalities into highly stable covalent organic frameworks (COFs). In this work, the irreversible three-component Doebner reaction is utilized synthesize four chemically quinoline-4-carboxylic acid DMCR-COFs (DMCR-1-3 and DMCR-1NH) equipped with an acid-base bifunctionality. These show superior photocatalytic H2O2 evolution (one of most important industrial oxidants) compared imine COF analogue (Imine-1). This achieved sacrificial oxidants but also in pure water under oxygen or air atmosphere. Furthermore, high photostability, durability, recyclability. MCR-COFs thus provide a viable materials' platform for solar chemical energy conversion.

Language: Английский

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Pyrene‐Based Covalent Organic Frameworks for Photocatalytic Hydrogen Peroxide Production

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(19)

Published: March 10, 2023

Four highly porous covalent organic frameworks (COFs) containing pyrene units were prepared and explored for photocatalytic H2 O2 production. The experimental studies are complemented by density functional theory calculations, proving that the unit is more active production than bipyridine (diarylamino)benzene reported previously. decomposition experiments verified distribution of over a large surface area COFs plays an important role in catalytic performance. Py-Py-COF though contains other which induces high due to dense concentration close proximity limited area. Therefore, two-phase reaction system (water-benzyl alcohol) was employed inhibit decomposition. This first report on applying pyrene-based generation.

Language: Английский

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Sulfone‐Modified Covalent Organic Frameworks Enabling Efficient Photocatalytic Hydrogen Peroxide Generation via One‐Step Two‐Electron O₂ Reduction

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(26)

Published: April 25, 2023

Abstract Photocatalytic oxygen reduction reaction (ORR) offers a promising hydrogen peroxide (H 2 O ) synthetic strategy, especially the one‐step two‐electron (2e − ORR route holds great potential in achieving highly efficient and selectivity. However, 2e is rarely harvested underlying mechanism for regulating pathways remains greatly obscure. Here, by loading sulfone units into covalent organic frameworks (FS‐COFs), we present an photocatalyst H generation via from pure water air. Under visible light irradiation, FS‐COFs exert superb yield of 3904.2 μmol h −1 g , outperforming most reported metal‐free catalysts under similar conditions. Experimental theoretical investigation reveals that accelerate separation photoinduced electron‐hole (e ‐h + pairs, enhance protonation COFs, promote adsorption Yeager‐type, which jointly alters process two‐step to one, thereby with high

Language: Английский

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Oxidation‐Reduction Molecular Junction Covalent Organic Frameworks for Full Reaction Photosynthesis of H₂O₂

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 62(9)

Published: Dec. 30, 2022

The full reaction photosynthesis of H2 O2 that can combine water-oxidation and oxygen-reduction without sacrificial agents is highly demanded to maximize the light-utilization overcome complex reaction-process anthraquinone-oxidation. Here, a kind oxidation-reduction molecular junction covalent-organic-framework (TTF-BT-COF) has been synthesized through covalent-coupling tetrathiafulvalene (photo-oxidation site) benzothiazole (photo-reduction site), which presents visible-light-adsorption region, effective electron-hole separation-efficiency photo-redox sites enables generation . Specifically, record-high yield (TTF-BT-COF, ≈276 000 μM h-1 g-1 ) for achieved among porous crystalline photocatalysts. This first work design COFs , might extend scope in production.

Language: Английский

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Solar‐to‐H₂O₂ Catalyzed by Covalent Organic Frameworks

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(49)

Published: Aug. 14, 2023

Abstract Benefiting from the excellent structural tunability, robust framework, ultrahigh porosity, and rich active sites, covalent organic frameworks (COFs) are widely recognized as promising photocatalysts in chemical conversions, emerged hydrogen peroxide (H 2 O ) photosynthesis 2020. H , serving an environmental‐friendly oxidant a liquid fuel, has attracted increasing researchers to explore its potential. Over past few years, numerous COFs‐based developed with encouraging achievements production, whereas no comprehensive review articles exist summarize this specific significant area. Herein we provide systematic overview of advances challenges COFs photocatalytic production. We first introduce priorities photosynthesis. Then, various strategies improve efficiency discussed. The perspective outlook for future emerging field finally offered. This timely will pave way development highly efficient practical production value‐added chemicals not limited .

Language: Английский

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Covalent Organic Frameworks Containing Dual O₂Reduction Centers for Overall Photosynthetic Hydrogen Peroxide Production

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 62(9)

Published: Dec. 28, 2022

Covalent organic frameworks (COFs) are highly desirable for achieving high-efficiency overall photosynthesis of hydrogen peroxide (H2 O2 ) via molecular design. However, precise construction COFs toward photosynthetic H2 remains a great challenge. Herein, we report the crystalline s-heptazine-based (HEP-TAPT-COF and HEP-TAPB-COF) with separated redox centers efficient production from pure water. The spatially orderly active sites in HEP-COFs can efficiently promote charge separation enhance photocatalytic production. Compared HEP-TAPB-COF, HEP-TAPT-COF exhibits higher efficiency integrating dual reduction s-heptazine triazine moieties. Accordingly, bearing remarkable solar-to-chemical energy 0.65 % high apparent quantum 15.35 at 420 nm, surpassing previously reported COF-based photocatalysts.

Language: Английский

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Covalent Organic Frameworks for Energy Conversion in Photocatalysis

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(34)

Published: April 24, 2023

Abstract Intensifying energy crises and severe environmental issues have led to the discovery of renewable sources, sustainable conversion, storage technologies. Photocatalysis is a green technology that converts eco‐friendly solar into high‐energy chemicals. Covalent organic frameworks (COFs) are porous materials constructed by covalent bonds show promising potential for converting chemicals owing their pre‐designable structures, high crystallinity, porosity. Herein, we highlight recent progress in synthesis COF‐based photocatalysts applications water splitting, CO 2 reduction, H O production. The challenges future opportunities rational design COFs advanced discussed. This Review expected promote further development toward photocatalysis.

Language: Английский

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Thiophene‐Containing Covalent Organic Frameworks for Overall Photocatalytic H₂O₂ Synthesis in Water and Seawater

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(38)

Published: Aug. 1, 2023

H2 O2 is a significant chemical widely utilized in the environmental and industrial fields, with growing global demand. Without sacrificial agents, simultaneous photocatalyzed synthesis through oxygen reduction reaction (ORR) water oxidation (WOR) dual channels from seawater green sustainable but still challenging. Herein, two novel thiophene-containing covalent organic frameworks (TD-COF TT-COF) were first constructed served as catalysts for via indirect 2e- ORR direct WOR channels. The photocatalytic production performance can be regulated by adjusting N-heterocycle modules (pyridine triazine) COFs. Notably, no just using air raw materials, TD-COF exhibited high yields of 4060 μmol h-1 g-1 3364 deionized natural seawater, respectively. Further computational mechanism studies revealed that thiophene was primary photoreduction unit ORR, while benzene ring (linked to imine bond) central photooxidation WOR. current work exploits COFs overall provides fresh insight into creating innovative photocatalyzing synthesis.

Language: Английский

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Efficient photocatalytic production of hydrogen peroxide using dispersible and photoactive porous polymers

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

Published: Oct. 28, 2023

Developing efficient artificial photocatalysts for the biomimetic photocatalytic production of molecular materials, including medicines and clean energy carriers, remains a fundamentally technologically essential challenge. Hydrogen peroxide is widely used in chemical synthesis, medical disinfection, energy. However, current industrial production, predominantly by anthraquinone oxidation, suffers from hefty penalties toxic byproducts. Herein, we report hydrogen protonation-induced dispersible porous polymers with good charge-carrier transport properties. Significant generation occurs under ambient conditions at an unprecedented rate 23.7 mmol g-1 h-1 apparent quantum efficiency 11.3% 450 nm. Combined simulations spectroscopies indicate that sub-picosecond ultrafast electron "localization" both free carriers exciton states catalytic reaction centers underlie remarkable performance polymers.

Language: Английский

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