Photocatalytic H2O2 production Systems: Design strategies and environmental applications

Chemical Engineering Journal, Journal Year: 2022, Volume and Issue: 451, P. 138489 - 138489

Published: Aug. 5, 2022

Language: Английский

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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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Boosting 2e− oxygen reduction reaction in garland carbon nitride with carbon defects for high-efficient photocatalysis-self-Fenton degradation of 2,4-dichlorophenol

Applied Catalysis B Environment and Energy, Journal Year: 2022, Volume and Issue: 307, P. 121185 - 121185

Published: Feb. 7, 2022

Language: Английский

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Coupled adsorption and photocatalysis of g-C3N4 based composites: Material synthesis, mechanism, and environmental applications

Chemical Engineering Journal, Journal Year: 2022, Volume and Issue: 453, P. 139755 - 139755

Published: Oct. 17, 2022

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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Constructing Synergistic Triazine and Acetylene Cores in Fully Conjugated Covalent Organic Frameworks for Cascade Photocatalytic H₂O₂ Production

Chemistry of Materials, Journal Year: 2022, Volume and Issue: 34(11), P. 5232 - 5240

Published: May 16, 2022

Covalent organic frameworks (COFs) are an ideal template for photocatalytic H2O2 synthesis because of the tunable chemical structures and semiconductor properties. However, photoactivity COFs is still under-improved due to inefficient intrinsic charge generation, fast recombination photogenerated charges, limited electron transport along frameworks. Herein, spatially separated synergistic triazine acetylene units first integrated into (EBA-COF BTEA-COF) production. The spatial separation cores leads efficient suppressed recombination, C═C linkage facilitates electrons over skeletons. Both experimental computational results suggested that synergistically promote in a two-electron pathway. EBA-COF showed attractive activity with production rate 1830 μmol h–1 gcat–1, superior most other COF-based catalysts. This study provides method designing photocatalysts active sites based on vinylene-linked COFs.

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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Directing Charge Transfer in a Chemical‐Bonded BaTiO₃@ReS₂ Schottky Heterojunction for Piezoelectric Enhanced Photocatalysis

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(29)

Published: May 13, 2022

The piezo-assisted photocatalysis system, which can utilize solar energy and mechanical simulteneously, is promising but still challenging in the environmental remediation field. In this work, a novel metal-semiconductor BaTiO3 @ReS2 Schottky heterostructure designed it shows high-efficiency on photocatalytic molecular oxygen activation. By combining experiment calculation results, distorted metal-phase ReS2 nanosheets are found to be closely anchored surface of nanorods, through interfacial ReO covalent bonds. not only forms electron-transfer channels also exhibits enhanced activation capacity, helpful produce more superoxide radicals. polarization field induced by piezoelectric lower barrier thus reduce transfer resistance photogenerated electrons directing . As result synergy effect between two components, untrahigh activity for degradation pollutants with an apparent rate constant 0.133 min-1 photocatalysis, 16.6 2.44 times as that piezocatalysis respectively. This performance higher than most reported -based systems. work paves way design materials using green energies nature.

Language: Английский

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Unraveling the Mechanism on Ultrahigh Efficiency Photocatalytic H₂O₂ Generation for Dual‐Heteroatom Incorporated Polymeric Carbon Nitride

Advanced Functional Materials, Journal Year: 2022, Volume and Issue: 32(38)

Published: July 13, 2022

Abstract Photocatalytic hydrogen peroxide (H 2 O ) production from dioxygen and water is regarded as a promising technology since it can achieve sustainable green solar‐to‐chemical energy conversion. Herein, oxygen potassium dual‐heteroatom incorporated polymeric carbon nitride (O/KCN) rationally designed for H generation with an ultrahigh rate of 309.44 µM h −1 mg , which surpasses that other C 3 N 4 ‐based photocatalysts. The enhanced performance be ascribed to the effective light absorption, fast charge transfer/separation, strong adsorption, highly selective two‐electron reduction reaction (ORR). Density functional theory calculations further confirm obtained O/KCN more favorable than others electrons migrating β spin‐orbital π* orbitals molecule, thus optimizing molecule activation promote formation intermediate species *OOH decrease barrier production. This work not only provides in‐depth insights photocatalytic mechanism, but also lays foundation development active photocatalysts environmental remediation

Language: Английский

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Bifunctional TiO2/COF S-scheme photocatalyst with enhanced H2O2 production and furoic acid synthesis mechanism

Applied Catalysis B Environment and Energy, Journal Year: 2023, Volume and Issue: 333, P. 122780 - 122780

Published: April 25, 2023

Language: Английский

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