Polarization Engineering of Covalent Triazine Frameworks for Highly Efficient Photosynthesis of Hydrogen Peroxide from Molecular Oxygen and Water

Advanced Materials, Journal Year: 2022, Volume and Issue: 34(28)

Published: May 7, 2022

Two-electron oxygen photoreduction to hydrogen peroxide (H2 O2 ) is seriously inhibited by its sluggish charge kinetics. Herein, a polarization engineering strategy demonstrated grafting (thio)urea functional groups onto covalent triazine frameworks (CTFs), giving rise significantly promoted separation/transport and obviously enhanced proton transfer. The thiourea-functionalized CTF (Bpt-CTF) presents substantial improvement in the photocatalytic H2 production rate 3268.1 µmol h-1 g-1 with no sacrificial agents or cocatalysts that over an order of magnitude higher than unfunctionalized (Dc-CTF), remarkable quantum efficiency 8.6% at 400 nm. Mechanistic studies reveal performance attributed prominently two-electron reduction reaction forming endoperoxide unit highly concentrated holes thiourea site. generated from water oxidation subsequently consumed (ORR), thereby boosting overall findings suggest powerful functional-groups-mediated method for development efficient metal-free polymer-based photocatalysts.

Language: Английский

---

Ionic Covalent Organic Frameworks for Energy Devices

Advanced Materials, Journal Year: 2021, Volume and Issue: 33(52)

Published: Oct. 8, 2021

Covalent organic frameworks (COFs) are a class of porous crystalline materials whose facile preparation, functionality, and modularity have led to their becoming powerful platforms for the development molecular devices in many fields (bio)engineering, such as energy storage, environmental remediation, drug delivery, catalysis. In particular, ionic COFs (iCOFs) highly useful constructing devices, functional groups can transport ions efficiently, nonlabile ordered all-covalent pore structures backbones provide ideal pathways long-term under harsh electrochemical conditions. Here, current research progress on use iCOFs specifically lithium-based batteries fuel cells, is reviewed terms iCOF backbone-design strategies, synthetic approaches, properties, engineering techniques, applications. categorized anionic or cationic COFs, how each these types lithium ions, protons, hydroxides illustrated. Finally, challenges future opportunities utilization described. This review will therefore serve reference state-of-the-art design application strategies focusing devices.

Language: Английский

---

Lighting up Micro-/Nanorobots with Fluorescence

Chemical Reviews, Journal Year: 2022, Volume and Issue: 123(7), P. 3944 - 3975

Published: Sept. 15, 2022

Micro-/nanorobots (MNRs) can be autonomously propelled on demand in complex biological environments and thus may bring revolutionary changes to biomedicines. Fluorescence has been widely used real-time imaging, chemo-/biosensing, photo-(chemo-) therapy. The integration of MNRs with fluorescence generates fluorescent unique advantages optical trackability, on-the-fly environmental sensitivity, targeting chemo-/photon-induced cytotoxicity. This review provides an up-to-date overview MNRs. After the highlighted elucidation about various propulsion mechanisms introductory information emphasis materials, we systematically illustrate design preparation strategies integrate substances their biomedical applications imaging-guided drug delivery, intelligent sensing In end, summarize main challenges provide outlook future directions work is expected attract inspire researchers from different communities advance creation practical application a broad horizon.

Language: Английский

---

The order–disorder conundrum: a trade-off between crystalline and amorphous porous organic polymers for task-specific applications

Journal of Materials Chemistry A, Journal Year: 2022, Volume and Issue: 10(33), P. 17077 - 17121

Published: Jan. 1, 2022

The review unravels the order–disorder conundrum in porous organic polymers view of task-specific applications through a comparative deliberation.

Language: Английский

---

Monolayer-Assisted Surface-Initiated Schiff-Base-Mediated Aldol Polycondensation for the Synthesis of Crystalline sp² Carbon-Conjugated Covalent Organic Framework Thin Films

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(9), P. 5203 - 5210

Published: Feb. 13, 2023

sp2 carbon-conjugated covalent organic frameworks (sp2c-COFs) with superb in-plane π-conjugations, high chemical stability, and robust framework structure are expected to be ideal films/membranes for a wide range of applications including energy-related devices optoelectronics. However, so far, sp2c-COFs have been mainly limited microcrystalline powders, this consequently hampered their performances in devices. Herein, we report simple methodology fabricate large-area, free-standing, crystalline sp2c-COF films (TFPT–TMT TB–TMT) on various solid substrates (e.g., fluorine-doped tin oxide, aluminum sheet, polyacrylonitrile membrane) by self-assembly monolayer-assisted surface-initiated Schiff-base-mediated aldol polycondensation (namely, SI-SBMAP). The resultant show lateral sizes up 120 cm2 tunable thickness from tens nanometers few micrometers. Owing the highly ordered quasi-1D channels, membrane-based osmotic power generator presents an output density 14.1 W m–2 under harsh conditions, outperforming most reported COF membranes as well commercialized benchmark (5 m–2). This work demonstrates interfacial fabrication green energy potential

Language: Английский

---

A Fully Conjugated Covalent Organic Framework with Oxidative and Reductive Sites for Photocatalytic Carbon Dioxide Reduction with Water

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(36)

Published: June 28, 2023

Constructing a powerful photocatalytic system that can achieve the carbon dioxide (CO2 ) reduction half-reaction and water (H2 O) oxidation simultaneously is very challenging but meaningful task. Herein, porous material with crystalline topological network, named viCOF-bpy-Re, was rationally synthesized by incorporating rhenium complexes as reductive sites triazine ring structures oxidative via robust -C=C- bond linkages. The charge-separation ability of viCOF-bpy-Re promoted low polarized π-bridges between units, efficient enables photogenerated electron-hole pairs, followed an intramolecular charge-transfer process, to form electrons involved in CO2 holes participate H2 O simultaneously. shows highest catalytic monoxide (CO) production rate (190.6 μmol g-1 h-1 about 100 % selectivity) oxygen (O2 evolution (90.2 among all catalysts sacrificial agents. Therefore, successfully achieved, this exhibited excellent stability catalysis process for 50 hours. structure-function relationship confirmed femtosecond transient absorption spectroscopy density functional theory calculations.

Language: Английский

---

Linkages Make a Difference in the Photoluminescence of Covalent Organic Frameworks

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(42)

Published: Aug. 19, 2023

Covalent organic frameworks (COFs) with structural designability and tunability of photophysical properties enable them to be a promising class luminescent materials by incorporating well-designed fluorescent units directly into the periodic skeletons. The COFs are mainly affected features, which determine conjugation degree, charge delocalization ability, exciton dynamics COFs. To understand relationship between COF structures their properties, two same pyrene chromophore but different linkages (imine or vinylene) were designed synthesized. Interestingly, endow huge differences in solid-state photoluminescence quantum yield (PLQY) for imine- vinylene-linked pyrene-based COFs, possess PLQY values 0.34 % 15.43 %, respectively. femtosecond-transient absorption spectra time-dependent density functional theory reveal charge-transfer pathways influence relaxation way fluorescence intensity. In addition, an effective white-light device was obtained coating on light-emitting diode strip.

Language: Английский

---

Efficient overall photosynthesis of H2O2 by the [email protected] S-scheme heterojunction

Science China Chemistry, Journal Year: 2024, Volume and Issue: 67(6), P. 1953 - 1960

Published: March 25, 2024

Language: Английский

---

A critical review of COFs-based photocatalysis for environmental remediation

Environmental Research, Journal Year: 2025, Volume and Issue: unknown, P. 121166 - 121166

Published: Feb. 1, 2025

Language: Английский

---

Facile Construction of Covalent Organic Framework Nanozyme for Colorimetric Detection of Uranium

Small, Journal Year: 2021, Volume and Issue: 17(44)

Published: Sept. 27, 2021

2D covalent organic frameworks (2D COFs) have been recognized as a novel class of photoactive materials owing to their extended π-electron conjugation and high chemical stabilities. Herein, new framework (Tph-BDP) is facilely synthesized by using porphyrin derivative an dye BODIPY (5,5-difluoro-2,8-diformyl-1,3,7,9-tetramethyl-10-phenyl-5H-dipyrrolo[1,2-c:2',1'-f][1,3,2]diazabori-nin-4-ium-5-uide) monomers for the first time, unique photosensitive properties endow them excellent simulated oxidase activity under 635 nm laser irradiation that can catalyze oxidation 3,3',5,5'-tetramethylbenzidine (TMB). Further findings demonstrate presence uranium (UO22+ ) coordinate with imines products TMB, thus modulating charge transfer process colored accompanied intensive aggregation remarkable color fading. This research provides preparation strategy COFs photocatalytic nanozyme activity, broadens applications simple colorimetric methods sensitive selective radionuclide detection.

Language: Английский

---