Covalent organic frameworks for direct photosynthesis of hydrogen peroxide from water, air and sunlight

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

Published: July 19, 2023

Solar-driven photosynthesis is a sustainable process for the production of hydrogen peroxide, efficiency which plagued by side reactions. Metal-free covalent organic frameworks (COFs) that can form suitable intermediates and inhibit reactions show great promise to photo-synthesize H2O2. However, insufficient formation separation/transfer photogenerated charges in such materials restricts H2O2 production. Herein, we provide strategy design donor-acceptor COFs greatly boost photosynthesis. We demonstrate optimal intramolecular polarity COFs, achieved using amounts phenyl groups as electron donors, maximize free charge generation, leads high yield rates (605 μmol g-1 h-1) from water, oxygen visible light without sacrificial agents. Combining in-situ characterization with computational calculations, describe how triazine N-sites N 2p states play crucial role H2O activation selective oxidation into further experimentally be efficiently produced tap, river or sea water natural sunlight air decontamination.

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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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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Reaction Pathways toward Sustainable Photosynthesis of Hydrogen Peroxide by Polymer Photocatalysts

Chemistry of Materials, Journal Year: 2022, Volume and Issue: 34(10), P. 4259 - 4273

Published: May 11, 2022

Harnessing solar energy to generate hydrogen peroxide (H2O2) from H2O and O2 via artificial photosynthesis is an attractive route, as this approach only uses sunlight the input. Organic polymers have emerged a promising class of materials for solar-driven H2O2 production, owing their virtually unlimited molecular building blocks rich bond-forming reactions. This distinctive feature leads existence different reaction pathways characterized by electron transfer numbers. For overall H2O2, reduction oxidation must occur concurrently. Thus, in-depth insights into these are crucial with eventual aim steering optimize efficiency. In perspective, we primarily focus on state-of-the-art progress in developing polymer photocatalysts coupling We also present key challenges opportunities production future. offer ample molecular-level design space. They now found extensive applications photochemical Therefore, perspective serves guideline designing toward sustainable has significant implications future development broad area solar-to-chemical conversion research.

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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Design Principles and Strategies of Photocatalytic H₂O₂ Production from O₂ Reduction

ACS ES&T Engineering, Journal Year: 2022, Volume and Issue: 2(6), P. 1068 - 1079

Published: Jan. 25, 2022

H2O2, as an important chemical and environmentally friendly oxidant, has been applied in various fields, such synthesis, pulp bleaching, disinfection, environmental remediation. Nevertheless, the industrial anthraquinone process for production of H2O2 is energy-intensive only suitable centralized H2O2. Photocatalytic from O2 reduction a promising approach on-site decentralized synthesis. Although photocatalysts have developed, efficiency still limited by narrow light absorption range, rapid charge recombination, slow surface reaction. In this perspective, we briefly introduce basic mechanism photocatalytic reduction. Subsequently, propose design principles discuss universal strategies enhancing performance production, aspects absorption, separation, catalytic reaction, reactor configurations. Finally, present our prospects suggestions development future. We hope that perspective can provide useful guidance rational efficient novel advance both insights practical applications production.

Language: Английский

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Solar Light Driven H₂O₂ Production and Selective Oxidations Using a Covalent Organic Framework Photocatalyst Prepared by a Multicomponent Reaction

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(29)

Published: May 8, 2023

A chemically stable 2D microporous COF (PMCR-1) was synthesized via the multicomponent Povarov reaction. PMCR-1 exhibits a remarkable and long-term photocatalytic H2 O2 production rate (60 h) from pure sea water under visible light. The is markedly enhanced when benzyl alcohol (BA) added as reductant, which also due to strong π-π interaction of BA with dangling phenyl moieties in pores introduced by Motivated concomitant oxidation benzaldehyde during formation, various organic substrates such amine methyl sulfide derivatives investigated. It shown that well-defined micropores enable size-selective oxidation.

Language: Английский

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Large electronegativity differences between adjacent atomic sites activate and stabilize ZnIn2S4 for efficient photocatalytic overall water splitting

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Jan. 6, 2024

Abstract Photocatalytic overall water splitting into hydrogen and oxygen is desirable for long-term renewable, sustainable clean fuel production on earth. Metal sulfides are considered as ideal hydrogen-evolved photocatalysts, but their component homogeneity typical sulfur instability cause an inert production, which remains a huge obstacle to water-splitting. Here, distortion-evoked cation-site doping of ZnIn 2 S 4 (D-O-ZIS) creates significant electronegativity differences between adjacent atomic sites, with 1 sites being electron-rich electron-deficient in the local structure –S –O sites. The strong charge redistribution character activates stable reactions at avoids common issue metal sulfide photocatalysis, while favor adsorption/desorption hydrogen. Consequently, water-splitting reaction has been realized D-O-ZIS remarkable solar-to-hydrogen conversion efficiency 0.57%, accompanying ~ 91% retention rate after 120 h photocatalytic test. In this work, we inspire universal design from perspective activate stabilize photocatalysts efficient

Language: Английский

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Conjugated Organic Polymers with Anthraquinone Redox Centers for Efficient Photocatalytic Hydrogen Peroxide Production from Water and Oxygen under Visible Light Irradiation without Any Additives

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(20), P. 12954 - 12963

Published: Oct. 11, 2022

The photocatalytic generation of hydrogen peroxide (H2O2) from H2O and O2 under visible light irradiation is a hopeful approach to achieve solar-to-chemical energy transformation. While the lack specific redox reaction centers still main reason for low H2O2 production efficiency, herein, we present conjugated organic polymer (AQTEE-COP) containing anthraquinone by Sonogashira cross-coupling between 2,6-dibromoanthraquinone (AQ) 1,1,2,2-tetrakis(4-ethynylphenyl)ethene. extended π-conjugated framework with an electron push–pull effect electron-donating tetraphenylethene moieties electron-withdrawing not only broadened absorption range but also promoted separation migration photo-induced charge carriers. Meanwhile, can serve as accept electrons transfer them adsorbed molecules subsequent production. well-defined structure AQTEE-COP task-specific anthracene provides molecular-level insights into mechanistic understanding O2. exhibits efficient initial rate 3204 μmol g–1 h–1 (λ ≥ 400 nm) without any additional photosensitizers, scavengers, or co-catalysts. This article protocol rational design pre-functionalized polymer-based materials

Language: Английский

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