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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Pyridyl‐Imine‐Functionalized Donor–Acceptor Covalent Organic Frameworks for Optimal Photosynthesis of Hydrogen Peroxide

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

Published: Feb. 3, 2025

Abstract The artificial photosynthesis of hydrogen peroxide (H 2 O ) using semiconductor photocatalysts is gaining attention as an eco‐friendly and energy‐efficient method. Covalent organic frameworks (COFs) show great promise in enhancing photocatalytic H production due to their tunable structures functional diversity. However, the efficiency generation close photoelectric properties COFs microenvironment active sites. Herein, synthesis pyridyl‐imine‐functionalized (PyIm‐COFs) featuring donor–acceptor (D–A) moieties improve reported. By employing benzothiadiazole (BT) units with varied fluorine substitutions, electronic environment sites, optimizing selective two‐electron (2e − oxygen reduction reaction (ORR), tuned. Among synthesized COFs, PyIm‐BT_F exhibits highest activity, achieving a rate 5342 µmol g −1 h . importance D–A rational design COF‐based photocatalysts, providing novel strategy for sustainable through optimized site environments, underscored.

Language: Английский

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Covalent Organic Frameworks for Photocatalysis

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

Published: Dec. 9, 2024

Abstract The global energy crisis and environmental concerns are driving research into renewable sustainable conversion storage technologies. Solar energy, as an ideal resource, has significant potential to contribute the goal of net‐zero carbon emissions if effectively harnessed converted a reliable storable form energy. Photocatalysts have convert sunlight chemical carriers. In this respect, covalent organic frameworks (COFs) shown great promise due their tunable structure on different length scales, high surface areas, beneficial optical properties such broad visible light absorption. This review offers comprehensive overview key developments in COF‐based photocatalysts for various applications, including water splitting, hydrogen peroxide generation, transformations, dioxide nitrogen reduction. underlying mechanisms, essential principles material design, structure‐function relationships COFs photocatalytic applications discussed. challenges faced by also summarized strategies enhance performance explained, improving crystallinity, regulating molecular structures, tailoring linkages, incorporating cocatalysts. Finally, critical proposed utilization photocatalytically generated chemicals value‐added products.

Language: Английский

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S‐Scheme Heterojunction Fabricated from Covalent Organic Framework and Quantum Dot for Enhanced Photosynthesis of Hydrogen Peroxide from Water and Air

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

Published: Sept. 16, 2024

Abstract Covalent organic frameworks (COFs) with stable crystalline porous structures and flexible assembly properties contribute to the direct photocatalytic synthesis of H 2 O meet growing global demand. To address challenges insufficient redox capacity photogenerated carrier recombination COFs, S‐scheme heterojunction is constructed from COFs quantum dots (QDs) improve production . Herein, 0D ZnCdS QDs (ZCS) uniformly anchor on surface a 2D conjugated tetrathiafulvalene‐based COF (TT‐COF), affording TT‐COF/ZCS. Formation effectively prevents agglomeration ZCS, modulates energy band structure TT‐COF, enhances migration carriers ability. As total consequence, optimized (TZ‐40) able afford in yield up 5171 µmol g −1 h under visible light irradiation , much higher than those for 2520 2647 The present result demonstrates great potential COFs/QDs‐based heterojunctions applications including production.

Language: Английский

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Remarkable increase in electrochemiluminescence of isomeric bipyridine-based covalent organic frameworks via regulating the direction of imine linkage for sensing application

Journal of Colloid and Interface Science, Journal Year: 2025, Volume and Issue: 684, P. 262 - 271

Published: Jan. 7, 2025

Language: Английский

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Achieving High zT with Carbon Nanotube/Conjugated Microporous Polymer Thermoelectric Nanohybrids by Meticulous Molecular Geometry Design

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(45)

Published: May 27, 2024

Abstract Conjugated microporous polymers (CMPs) are characterized by high physical and chemical stabilities along with low thermal conductivities due to their conjugated frameworks, making them promising candidates for thermoelectric application. However, the advancement of CMPs within field is considerably hampered inadequate electrical conductivity unfavorable processability. Herein, highly‐conducting carbon nanotubes (CNTs) dispersed in two solvents (1,2‐dichlorobenzene N ‐methyl‐2‐pyrrolidone) fabricate p‐ n‐type CNT/CMP nanohybrids. Additionally, unique synthesized elucidate impacts structures pore architectures on properties Finally, differing steric hindrance effects CMPs, performance can be tuned under varying circumstances. The synergetic efficient dispersion capability yield optimized figure merit ( zT ) values 0.053 0.13 at 303 K nanohybrids, respectively. This investigation presents an alternative approach building nanohybrids operating near ambient temperature via solvent doping effect structure design thereby establishing CMP‐based materials as

Language: Английский

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Pyrimidine-containing covalent organic frameworks for efficient photosynthesis of hydrogen peroxide via one-step two electron oxygen reduction process

Nano Research, Journal Year: 2024, Volume and Issue: 17(11), P. 9498 - 9506

Published: Aug. 17, 2024

Language: Английский

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Isomerization of Covalent Organic Frameworks for Efficiently Activating Molecular Oxygen and Promoting Hydrogen Peroxide Photosynthesis

Small, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 27, 2024

Abstract Constitutional‐isomerized covalent organic frameworks (COFs), constructed by swapping monomers around imine bonds, have attracted attention for their distinct optoelectronic properties, which significantly impact photocatalytic performance. However, limited research has delved into the inherent relationship between isomerization and enhancement of H 2 O photosynthesis. Herein, a pair isomeric COFs linked bonds (PB‐PT‐COF PT‐PB‐COF) is synthesized, it proved that exhibit different rate‐determining steps in generation process , resulting twofold increase efficiency. Specifically, PT‐PB‐COF demonstrates effective adsorption activation molecular oxygen (O + e − → •O ), leading to significant improvement In contrast, PB‐PT‐COF exhibits robust interaction with O, enabling direct oxidation (H h ). This study provides thorough understanding intrinsic mechanism underlying constitutional‐isomerized generation, offering insights further optimizing building units.

Language: Английский

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Regulating Benzothiadiazole-Based Covalent–Organic Frameworks to Boost Hydrogen Peroxide Photosynthesis and Pathogenic Bacterial Elimination

ACS Materials Letters, Journal Year: 2025, Volume and Issue: unknown, P. 811 - 819

Published: Jan. 31, 2025

Language: Английский

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10% Conversion of Imine into Thiazole in Covalent Organic Frameworks for Efficient Photocatalytic H₂O₂ Generation

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

Published: March 17, 2025

Abstract The 5–10 nm exciton diffusion distance for most organic semiconductors is much less than the particle size of 2D covalent frameworks (COFs). As a result, local structure change in small domain COFs, rather whole particles, could effectively promote charge transfer photocatalysis. Herein, three‐component condensation used to preparing four mixed imine‐ and thiazole‐linked donor‐acceptor (D–A) COFs. In contrast 100% imine ca. 90% 10% materials have 77–95% higher photocatalytic hydrogen peroxide (H 2 O ) production rate pure water due more prolonged lifetime excitation state. particular, USTB‐10‐S exhibits H generation 5041 µmol g −1 h . Coupling with benzyl alcohol as sacrificial reagent, its further increased 16152 , superior COF‐based photocatalysts. This work illustrates proof‐of‐concept that COFs tiny amount able significantly enhance separation thus performance, inspiring development defect engineering field

Language: Английский

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