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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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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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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Light-Induced Variation of Lithium Coordination Environment in g-C₃N₄ Nanosheet for Highly Efficient Oxygen Reduction Reactions

ACS Nano, Journal Year: 2024, Volume and Issue: 18(6), P. 5206 - 5217

Published: Jan. 31, 2024

The structure and electronic state of the active center in a single-atom catalyst undergo noticeable changes during dynamic catalytic process. metal atom is not well demonstrated manner. This study that Li atoms, serving as centers, can migrate on C3N4 monolayer or between monolayers when exposed to light irradiation. migration alters local coordination environment nanosheets, leading significant enhancement photocatalytic activity. H2O2 process could be maintained for 35 h with 920 mmol/g record-high yield, corresponding 0.4% concentration, which far greater than value (0.1%) practical application wastewater treatment. Density functional theory calculations indicated Li-coordinated structures contributed superhigh

Language: Английский

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Linkage-engineered donor–acceptor covalent organic frameworks for optimal photosynthesis of hydrogen peroxide from water and air

Nature Catalysis, Journal Year: 2024, Volume and Issue: 7(2), P. 195 - 206

Published: Feb. 13, 2024

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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Linkage Microenvironment of Azoles‐Related Covalent Organic Frameworks Precisely Regulates Photocatalytic Generation of Hydrogen Peroxide

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(36)

Published: July 18, 2023

Artificial H2 O2 photosynthesis by covalent organic frameworks (COFs) photocatalysts is promising for wastewater treatment. The effect of linkage chemistry COFs as functional basis to photoelectrochemical properties and photocatalysis remains a significant challenge. In this study, three kinds azoles-linked including thiazole-linked TZ-COF, oxazole-linked OZ-COF imidazole-linked IZ-COF were successfully synthesized. More accessible channels charge transfer constructed in TZ-COF via the donor-π-acceptor structure between thiazole pyrene linker, leading efficient suppression photoexcited recombination. Density theory calculations support experimental studies, demonstrating that more favorable formation *O2 intermediate production than oxazole imidazole linkages. real active sites located at benzene ring fragment unit azole linkage.

Language: Английский

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Versatile Photoelectrocatalysis Strategy Raising Up the Green Production of Hydrogen Peroxide

Advanced Energy Materials, Journal Year: 2023, Volume and Issue: 13(14)

Published: March 1, 2023

Abstract H 2 O plays an irreplaceable role in many aspects of human society, such as paper bleaching, medical disinfection, wastewater treatment, organic synthesis, hydrometallurgy and the electronic industry. However, unsustainability current industrial production process traditional anthraquinone has a serious conflict with green sustainable development. The photo/electrocatalytic from renewable energy advantages being more economical, low‐carbon green, line requirements economy. These catalytic methods have played demonstrative development small molecules, contributing to fundamental understanding general catalysis providing scientific perspective for future new cycles. In this review, authors aim integrate reaction mechanism photocatalytic electrocatalytic production, summarize application recent years, assess modern technologies promoted research, including flux equipment coproduction, etc. This review intends provide clear logic profile directions calls researchers insights into field.

Language: Английский

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Molecular Heptazine–Triazine Junction over Carbon Nitride Frameworks for Artificial Photosynthesis of Hydrogen Peroxide

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(48)

Published: Sept. 29, 2023

Revealing the photocatalytic mechanism between various junctions and catalytic activities has become a hotspot in systems. Herein, an internal molecular heptazine/triazine (H/T) junction crystalline carbon nitride (HTCN) is constructed devoted to selective two-electron oxygen reduction reaction (2e- ORR) for efficient hydrogen peroxide (H2 O2 ) production. In-situ X-ray diffraction spectra under temperatures authenticate successful formation of H/T HTCN during calcining process rather than physically mixing. The increased surface photovoltage transient signals, decreased exciton binding energy undoubtably elucidate that obvious increasement carrier density diffusion capability photogenerated electrons are realized over HTCN. Additionally, analyses situ photoirradiated Kelvin probe force microscopy femto-second absorption reveal construction strong built-in-electric field existence majority long-lived shallow trapped associated with HTCN, respectively. Benefiting from these, results exhibit incredible improvement (96.5-fold) H2 This novel work provides comprehensive understanding reactive charges strengthening driving-force production, which opens potential applications enhancing PCN-based redox reactions.

Language: Английский

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Covalent Organic Frameworks Enable Sustainable Solar to Hydrogen Peroxide

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 34(12)

Published: Dec. 6, 2023

Abstract As a chemical product with rapidly expanding demand in the field of modern energy and environmental applications, hydrogen peroxide (H 2 O ) has garnered widespread attention. However, existing industrial production H is plagued by high consumption, harmful waste emission, severe safety issues, making it difficult to satisfy environmental/economic concept. Artificial photosynthesis offers viable strategy for green sustainable since uses sunlight as an source initiate reaction oxygen water produce . Among various photocatalysts, covalent organic frameworks (COFs), featuring highly ordered skeletons well‐defined active sites, have emerged promising photocatalysts production. This review presents nascent burgeoning area photocatalytic based on COFs. First, brief overview technology provided, followed detailed introduction principles evaluation generation. Subsequently, latest research progress judicious design COFs expounded, particular emphasis manipulating electronic structures redox sites. Finally, outlook challenges future opportunities proposed, hope stimulating further explorations novel molecular‐designed photosynthesis.

Language: Английский

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