Structural Motifs in Covalent Organic Frameworks for Photocatalysis

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: March 10, 2024

Abstract Covalent organic frameworks (COFs) attract significant attention due to their ordered, crystalline, porous, metal‐free, and predictable structures. These unique characteristics offer great opportunities for the diffusion transmission of photogenerated charges during photocatalysis. Currently, a considerable number COFs are used as metal‐free semiconductor photocatalysts. This review aims understand relationships between structure photocatalysis performance provides in‐depth insight into synthetic strategy improve performance. Subsequently, focuses on structural motif in sustainable photocatalytic hydrogen evolution, carbon dioxide reduction, peroxide generation, compound transformations. Last, conjunction with progress achieved challenges yet be overcome, candid discussion is undertaken regarding field COF photocatalysis, accompanied by presentation potential research avenues future directions. seeks provide readers comprehensive understanding pivotal role robust guidance innovative utilization

Language: Английский

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Rationally Designed Cyclooctatetrathiophene‐Based Porous Aromatic Frameworks (COTh‐PAFs) for Efficient Photocatalytic Hydrogen Peroxide Production

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(18)

Published: March 7, 2024

Constructing stable and efficient photocatalysts for H

Language: Английский

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Regulating the Topology of Covalent Organic Frameworks for Boosting Overall H₂O₂ Photogeneration

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(24)

Published: April 12, 2024

Photocatalytic oxygen reduction reactions and water oxidation are extremely promising green approaches for massive H

Language: Английский

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Covalent Organic Frameworks for Photocatalytic Hydrogen Peroxide Generation

ACS Materials Letters, Journal Year: 2024, Volume and Issue: 6(5), P. 2007 - 2049

Published: April 17, 2024

Hydrogen peroxide (H2O2), a valuable chemical, is widely used as powerful oxidizing agent in chemical synthesis, pharmaceuticals, medical disinfection, and environmental treatment industries. Currently, over 95% of H2O2 produced industrially using the anthraquinone process, which associated with its high energy consumption hazardous byproducts. Therefore, photochemical synthesis from water oxygen covalent organic framework based photocatalysts have attracted considerable attention. This review aims to outline recent achievements, challenges future prospects COFs heterogeneous for sustainable generation. We summarize chronological development COFs, different mechanisms involved, detailed experiments quantification methods photocatalytic The puts forward an outlook, highlighting advantages limitations anticipate that this will provide insight into current progress inspire next-generation production.

Language: Английский

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Programming Tetrathiafulvalene‐Based Covalent Organic Frameworks for Promoted Photoinduced Molecular Oxygen Activation

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(29)

Published: May 6, 2024

Abstract Despite the pivotal role of molecular oxygen (O 2 ) activation in artificial photosynthesis, efficiency is often restricted by sluggish exciton dissociation and charge transfer kinetics within polymer photocatalysts. Herein, we propose two tetrathiafulvalene (TTF)‐based imine‐linked covalent organic frameworks (COFs) with tailored donor‐acceptor (D–A) structures, TTF‐PDI‐COF TTF‐TFPP‐COF, to promote O activation. Because enhanced electron push‐pull interactions that facilitated separation behavior, exhibited superior photocatalytic activity electron‐induced reactions over TTF‐TFPP‐COF under visible light irradiation, including photosynthesis ( E )‐3‐amino‐2‐thiocyano‐ α , β ‐unsaturated compounds H . These findings highlight significant potential rational design COFs D–A configurations as suitable candidates for advanced applications.

Language: Английский

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Carbon Quantum Dots Confined into Covalent Triazine Frameworks for Efficient Overall Photocatalytic H₂O₂ Production

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(29)

Published: March 14, 2024

Abstract Porous organic polymers have an outstanding performance in the field of photocatalysis with advantage diverse structure composition and purposeful molecular design. However, inherent high impedance poor electrical conductivity semiconductors still restrict charge transfer efficiency thus discount photocatalytic performance. Herein, study reports a highly conductive covalent triazine framework (CTF) loading carbon quantum dots (CQDs) into porous as electron transport medium. The addition CQDs (0.5 wt%) can enhance electronic CTF by tenfold. In addition, as‐prepared CQD‐CTFs express much‐promoted separation efficiency. Furthermore, embedded improve oxidization capacity increase affinity H + due to more negative zeta potential. enhanced oxidizing ability increased are positive for water oxidation reaction (WOR) oxygen reduction (ORR) process hydrogen peroxide (H 2 O ) generation, respectively. optimized CQD‐CTF exhibits generation rate up 1036 µmol g −1 h pure without any sacrificial agent under visible light, which is 4.6 times than pristine CTF. This work provides new idea efficient production semiconductors.

Language: Английский

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Structurally Locked High-Crystalline Covalent Triazine Frameworks Enable Remarkable Overall Photosynthesis of Hydrogen Peroxide

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(43), P. 29943 - 29954

Published: Oct. 17, 2024

The development of green and efficient hydrogen peroxide (H

Language: Английский

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Enhancing photocatalytic hydrogen peroxide generation by tuning hydrazone linkage density in covalent organic frameworks

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

Published: Jan. 8, 2025

The conversion of solar energy into chemical or high-value chemicals has attracted considerable research interest in the context global crisis. Hydrogen peroxide (H2O2) is a versatile and powerful oxidizing agent widely used synthesis medical disinfection. H2O2 also serves as clean source fuel cells, generating electricity with zero-carbon emissions. Recently, sustainable production from water oxygen using covalent organic frameworks (COFs) photocatalysts attention; however, systematic studies highlighting role linkages determining photocatalytic performance are scarce. Under these circumstances, herein, we demonstrate that varying imine hydrazone within framework significantly influences production. COFs high-density linkages, providing optimal docking sites for oxygen, enhance generation activity (1588 μmol g−1 h−1 pure air), leading to highly efficient solar-to-chemical conversion. This work systematically investigates effect linkage density on enhancement hydrogen generation, aim achieving high-performance photocatalysis.

Language: Английский

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Hydroxyl-Functionalized Donor–Acceptor Covalent Organic Frameworks for Efficient Photocatalytic Hydrogen Peroxide Production under Visible Light

ACS Catalysis, Journal Year: 2025, Volume and Issue: unknown, P. 3584 - 3594

Published: Feb. 13, 2025

Photocatalytic hydrogen peroxide (H2O2) production via the oxygen reduction reaction (ORR) provides a promising and energy-saving alternative to traditional energy-intensive anthraquinone process. Nevertheless, how decrease energy barrier of two-electron (2e–) ORR process photosynthesize H2O2 efficiently is still challenging. Herein, three hydroxyl-functionalized donor–acceptor covalent organic frameworks (COFs) are synthesized for photocatalytic under visible-light irradiation (420 ≤ λ 780 nm). It observed that dihydroxyl functionalization (2,5-DhaTph 2,3-DhaTph) facilitates transportation photogenerated carriers between acceptor donor units accelerates kinetics rate-limiting step when comparing with monohydroxyl (2-DhaTph). Further, 2,5-DhaTph para-position hydroxyl shows higher photosynthesis efficiency than 2,3-DhaTph (ortho-positioned hydroxyl), probably due greater exposure catalytically active sites. This supported by better structural symmetry 2,5-DhaTph, which contributes crystallinity specific surface areas. Electron paramagnetic resonance (EPR) spectra theoretical calculations show produces *OOH intermediates reduced barrier, resulting in high rate 2103.1 μmol h–1 g–1. Regulating amount substituents their location on COFs an effective strategy boost carrier transfer reduce O2-to-H2O2 conversion.

Language: Английский

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Insights into excitonic behavior in single-atom covalent organic frameworks for efficient photo-Fenton-like pollutant degradation

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

Published: Jan. 17, 2025

The generation of radicals through photo-Fenton-like reactions demonstrates significant potential for remediating emerging organic contaminants (EOCs) in complex aqueous environments. However, the excitonic effect, induced by Coulomb interactions between photoexcited electrons and holes, reduces carrier utilization efficiency these systems. In this study, we develop Cu single-atom-loaded covalent frameworks (CuSA/COFs) as models to modulate effects. Temperature-dependent photoluminescence ultrafast transient absorption spectra reveal that incorporating acenaphthene units into linker (CuSA/Ace-COF) significantly exciton binding energy (Eb). This modification not only enhances peroxymonosulfate adsorption at active sites but also facilitates rapid electron transfer promotes selective hydroxyl radical generation. Compared CuSA/Obq-COF (Eb = 25.6 meV), CuSA/Ace-COF 12.2 meV) shows a 39.5-fold increase pseudo-first-order rate constant sulfamethoxazole degradation (0.434 min-1). work provides insights modulating behavior single-atom catalysts via engineering EOCs degradation.

Language: Английский

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