Linkage Microenvironment Modulation in Triazine‐Based Covalent Organic Frameworks for Enhanced Photocatalytic Hydrogen Peroxide Production

Small, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 26, 2025

Abstract Covalent organic frameworks (COFs), known for the precise tunability of molecular structures, hold significant promise photocatalytic hydrogen peroxide (H 2 O ) production. Herein, by systematically altering quinoline (QN) linkages in triazine (TA)‐based COFs via multi‐component reactions, six R‐QN‐TA‐COFs are synthesized with identical skeletons but different substituents. The fine‐tuning optoelectronic properties and local microenvironment is allowed, thereby optimizing charge separation improving interactions dissolved oxygen. Consequently, MeO‐QN‐TA‐COF customized to achieve an impressive rate H production up 7384 µmol g⁻ 1 h⁻ under air atmosphere water without any sacrificial agents, surpassing most reported COF photocatalysts. Its high stability demonstrated through five consecutive recycling experiments characterization recovered COF. reaction mechanism further investigated using a suite quenching experiments, situ spectroscopic analysis, theoretical calculations. enhanced over 2e⁻ oxygen reduction oxidation pathways. Overall, crucial role linkage modulation design solar‐driven effective

Language: Английский

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A Covalent Organic Framework as Photocatalyst for Smart Conversion Between Photooxidation and Photoreduction and H₂O₂ Production in Full pH Environment

Advanced Materials, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 7, 2025

Abstract Developing multifunctional photocatalysts with intelligent self‐adjusting is of great significance in the photocatalytic process. Herein, a smart covalent organic framework (Por‐HQ‐COF) phenol‐quinone conversion structure pH changes constructed for photooxidation, photoreduction, and H 2 O production. As photocatalyst, Por‐HQ‐COF can convert into Por‐BQ‐COF intelligently trigger including solution pH, vice versa. The reconstruction not only significantly alters morphologies specific surface areas COF, but also leads to an entirely change band energy charge distribution influence photoelectric properties. result, under acidic conditions, converts automatically photoreduce high concentration Cr(VI) Cr(III) efficiently. Under neutral superoxide anions (·O − ) initiate accelerate photooxidation degrade high‐concentration TC. alkaline Por‐BQ‐COF, effectively photosynthesize (1525 µmol h −1 g at λ > 420 nm) absence any sacrificial reagents, reveal strong alkalinity lower barrier hydrogen extraction from clarify active sites This work provides new strategy developing fulfill application across full environment.

Language: Английский

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Dual‐Functional Benzotrithiophene‐Based Covalent Organic Frameworks for Photocatalytic Detoxification of Mustard Gas Simulants and Antibacterial Defense

Small, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 17, 2025

Abstract The persistent threats posed by toxic chemical warfare agents (CWAs) such as mustard gas (bis(2‐chloroethyl) sulfide, HD) and bacterial contaminants demand the development of innovative, sustainable mitigation strategies. Photocatalytic processes that generate reactive oxygen species (ROS) offer a promising dual‐functional approach for both detoxification antibacterial defense. In this study, two structurally analogous covalent organic frameworks (COFs), BPY‐COF BD‐COF, are synthesized using benzotrithiophene donor unit paired with bipyridine biphenyl, respectively. These COFs exhibit high crystallinity, broad‐spectrum light absorption, efficient charge carrier transport, demonstrating superior performance due to incorporation heteroatoms. achieved ultrafast simulant 2‐chloroethyl ethyl sulfide (CEES) half‐life 35 min 100% selectivity sulfoxide (CEESO) under white LED light, outperforming BD‐COF. Additionally, electrospun composite fibers containing 40 wt.% maintained comparable CEES degradation rates exhibited over 99% efficiency against Escherichia coli Bacillus subtilis within 60 min. findings highlight potential multifunctional photocatalyst integrated applications in defense, addressing critical challenges public health safety.

Language: Английский

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Deciphering a volcano-shaped relationship between radical stability and reticular electrochemiluminescence

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Feb. 24, 2025

Electrochemiluminescence (ECL) is a light-emitting process in which the stability of electrochemically generated radicals has crucial impact on efficiency and durability excited state generation. Therefore, deciphering relationship between radical ECL performance highly appealing. In this work, three sp2 carbon-conjugated covalent organic framework (COF) reticular nanoemitters compositing same pyrene luminophores but different acrylonitrile linkers are designed with progressive electron affinities, named as CN-COF-1, 2, 3. By precisely modulating affinity CN-COFs, volcano discovered 78 folds enhancement intensity. Density functional theoretical calculations indicate that CN-COF-2 exhibits moderate stabilization capacity well efficient transport cores, facilitating Significantly, appropriate not only achieves self-enhanced cathodic also promotes The rational regulation paves way for developing decoding fundamentals. Deciphering electrochemiluminescence important since an Here, authors describe shaped via acrylonitrile-linked frameworks.

Language: Английский

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Halogen atom-induced local asymmetric electron in covalent organic frameworks boosts photosynthesis of hydrogen peroxide from water and air

Matter, Journal Year: 2025, Volume and Issue: unknown, P. 102076 - 102076

Published: March 1, 2025

Language: Английский

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