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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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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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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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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In Situ Synthesis of Chemically Bonded 2D/2D Covalent Organic Frameworks/O‐Vacancy WO₃ Z‐Scheme Heterostructure for Photocatalytic Overall Water Splitting

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(33)

Published: June 15, 2023

Abstract Covalent organic frameworks (COFs) have shown great promise for photocatalytic hydrogen evolution via water splitting. However, the four‐electron oxidation of remains elusive toward oxygen evolution. Enabling this pathway is critical to improve yield and maximize atom utilization efficiency. A Z‐scheme heterojunction proposed overcoming fundamental issues in COF‐based overall splitting (OWS), such as inefficient light absorption, charge recombination, poor ability. It that construction a novel 2D/2D through situ growth COFs on O‐vacancy WO 3 nanosheets (Ov‐WO ) WOC chemical bond can remarkably promote OWS. Benefiting from synergistic effect between enhanced built‐in electric field by interfacial bond, strong ability Ov‐WO 3, ultrathin structure TSCOF, both separation efficiency photogenerated electron–hole pairs be significantly enhanced. An impressive half‐rection rate 593 mmol h −1 g 146 (hydrogen) 68 (oxygen) µmol are achieved COF‐WO (TSCOFW) composite. This with two‐step excitation precisely cascaded charge‐transfer makes it responsible efficient solar‐driven OWS without sacrificial agent.

Language: Английский

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Regulating Relative Nitrogen Locations of Diazine Functionalized Covalent Organic Frameworks for Overall H₂O₂ Photosynthesis

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(41)

Published: Aug. 26, 2023

Nitrogen-heterocycle-based covalent organic frameworks (COFs) are considered promising candidates for the overall photosynthesis of hydrogen peroxide (H2 O2 ). However, effects relative nitrogen locations remain obscured and photocatalytic performances COFs need to be further improved. Herein, a collection functionalized by various diazines including pyridazine, pyrimidine, pyrazine have been judiciously designed synthesized photogeneration H2 without sacrificial agents. Compared with pyrimidine pyrazine, pyridazine embedded in TpDz tends stabilize endoperoxide intermediate species, leading toward more efficient direct 2e- oxygen reduction reaction (ORR) pathway. Benefiting from effective electron-hole separation, low charge transfer resistance, high-efficiency ORR pathway, an excellent production rate 7327 μmol g-1 h-1 solar-to-chemical conversion (SCC) value 0.62 % has achieved TpDz, which ranks one best COF-based photocatalysts. This work might shed fresh light on rational design functional targeting photocatalysts production.

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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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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