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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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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COF/In₂S₃ S‐Scheme Photocatalyst with Enhanced Light Absorption and H₂O₂‐Production Activity and fs‐TA Investigation

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(24)

Published: Feb. 27, 2024

Photocatalytic hydrogen peroxide (H

Language: Английский

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Site Engineering of Covalent Organic Frameworks for Regulating Peroxymonosulfate Activation to Generate Singlet Oxygen with 100 % Selectivity

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(43)

Published: Sept. 5, 2023

Singlet oxygen (1 O2 ) is an excellent reactive species (ROSs) for the selective conversion of organic matter, especially in advanced oxidation processes (AOPs). However, due to huge dilemma synthesizing single-site type catalysts, control and regulation 1 generation AOPs still challenging underlying mechanism remains largely obscure. Here, taking advantage well-defined flexibly tunable sites covalent frameworks (COFs), we report first achievement precisely regulating ROSs peroxymonosulfate (PMS)-based by site engineering COFs. Remarkably, COFs with bipyridine units (BPY-COFs) facilitate PMS activation via a nonradical pathway 100 % , whereas biphenyl-based (BPD-COFs) almost identical structures activate produce radicals (⋅OH SO4.- ). The BPY-COFs/PMS system delivers boosted performance degradation target pollutants from water, which ca. 9.4 times that its BPD-COFs counterpart, surpassing most reported PMS-based systems. Mechanism analysis indicated highly electronegative pyridine-N atoms on BPY-COFs provide extra adsorb terminal H PMS, resulting simultaneous adsorption O one pyridine ring, facilitates cleavage S-O bond generate .

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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The photocatalytic H2O2 production by metal-free photocatalysts under visible-light irradiation

Applied Catalysis B Environment and Energy, Journal Year: 2023, Volume and Issue: 341, P. 123271 - 123271

Published: Sept. 6, 2023

Language: Английский

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Clean Production of Hydrogen Peroxide: A Heterogeneous Solar‐Driven Redox Process

Advanced Energy Materials, Journal Year: 2023, Volume and Issue: 13(36)

Published: Aug. 6, 2023

Abstract Hydrogen peroxide is an essential chemical that attracting strong attention for energy and environmental applications. However, the struggle between growing market demand unsustainability of conventional anthraquinone method motivates exploration alternative H 2 O production processes. Although several new processes have been proposed, environmental‐friendly solar‐driven attracts most because only inputs water, oxygen, light energy. The rational design functional photo‐responsive catalysts promotes in photocatalytic photoelectrocatalytic approaches. These are, general, achieved by facilitating preferential adsorption key intermediates OOH*/OH*/O*, enhancing absorption, promoting charge separation, accelerating surface transfer with selective number involved charges. This review systematically summarizes strategies photo(electro)catalysts toward via both water oxidation oxygen reduction pathways. Though route perceived as more popular community, emerging a convincing alternative. Furthermore, prevailing hypotheses, state‐of‐the‐art catalysts, critical challenges, perspectives are discussed depth. aims to enhance comprehension this research field promote interest sustainable production.

Language: Английский

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