Orderly Porous Covalent Organic Frameworks-based Materials: Superior Adsorbents for Pollutants Removal from Aqueous Solutions

The Innovation, Journal Year: 2021, Volume and Issue: 2(1), P. 100076 - 100076

Published: Jan. 10, 2021

Covalent organic frameworks (COFs) are a new type of crystalline porous polymers known for chemical stability, excellent structural regularity, robust framework, and inherent porosity, making them promising materials capturing various types pollutants from aqueous solutions. This review thoroughly presents the recent progress advances COFs COF-based as superior adsorbents efficient removal toxic heavy metal ions, radionuclides, pollutants. Information about interaction mechanisms between summarized macroscopic microscopic standpoints, including batch experiments, theoretical calculations, advanced spectroscopy analysis. The adsorption properties assessed compared with other widely used adsorbents. Several commonly strategies to enhance materials' performance relationship property sorption ability also discussed. Finally, summary perspective on opportunities challenges proposed provide some inspiring information designing fabricating environmental pollution management.

Language: Английский

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Application of MOFs and COFs for photocatalysis in CO2 reduction, H2 generation, and environmental treatment

EnergyChem, Journal Year: 2022, Volume and Issue: 4(4), P. 100078 - 100078

Published: June 25, 2022

Language: Английский

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Porphyrin-based frameworks for oxygen electrocatalysis and catalytic reduction of carbon dioxide

Chemical Society Reviews, Journal Year: 2021, Volume and Issue: 50(4), P. 2540 - 2581

Published: Jan. 1, 2021

The recent progress made on porphyrin-based frameworks and their applications in energy-related conversion technologies (e.g., ORR, OER CO₂RR) storage Zn–air batteries).

Language: Английский

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Photochemical and Electrochemical Applications of Proton-Coupled Electron Transfer in Organic Synthesis

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(2), P. 2017 - 2291

Published: Nov. 23, 2021

We present here a review of the photochemical and electrochemical applications multi-site proton-coupled electron transfer (MS-PCET) in organic synthesis. MS-PCETs are redox mechanisms which both an proton exchanged together, often concerted elementary step. As such, MS-PCET can function as non-classical mechanism for homolytic bond activation, providing opportunities to generate synthetically useful free radical intermediates directly from wide variety common functional groups. introduction practitioner’s guide reaction design, with emphasis on unique energetic selectivity features that characteristic this class. then chapters oxidative N–H, O–H, S–H, C–H homolysis methods, generation corresponding neutral species. Then, reductive PCET activations involving carbonyl, imine, other X═Y π-systems, heteroarenes, where ketyl, α-amino, heteroarene-derived radicals be generated. Finally, we asymmetric catalysis materials device applications. Within each chapter, subdivide by group undergoing homolysis, thereafter type transformation being promoted. Methods published prior end December 2020 presented.

Language: Английский

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Strategies and Challenges on Selectivity of Photocatalytic Oxidation of Organic Substances

Advanced Energy Materials, Journal Year: 2021, Volume and Issue: 11(8)

Published: Jan. 20, 2021

Abstract Most organic compounds are conventionally synthesized under high temperature and elevated pressure, resulting in significant energy consumption wastage. Heterogeneous photocatalytic oxidation has the potential to provide a green route for synthesis of majority industrially important chemicals. The major limiting factor affecting efficiency is lack selectivity; therefore, substantial effort been devoted solving this problem. Responding fast‐moving progress, review gives an overview fundamental understanding reactive oxygen species involved oxidations furthermore, general mechanisms few crucial reactions. focus critical on discussion diverse strategies improve selectivity value chemicals, including band engineering, metal loading, hybrid materials, defect with primary aim highlighting catalyst design protocols based reaction mechanism. Finally, difficulties challenges developing highly selective photocatalysts comprehensively discussed order help direct future research.

Language: Английский

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Covalent organic framework-based materials for energy applications

Energy & Environmental Science, Journal Year: 2020, Volume and Issue: 14(2), P. 688 - 728

Published: Nov. 11, 2020

The recent progress in the synthesis and energy applications of covalent organic frameworks has been elaborated this review article.

Language: Английский

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Tuning excited state electronic structure and charge transport in covalent organic frameworks for enhanced photocatalytic performance

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Feb. 27, 2023

Covalent organic frameworks (COFs) represent an emerging class of photocatalysts. However, their complicated structures lead to indeterminacy about photocatalytic active sites and reaction mechanisms. Herein, we use reticular chemistry construct a family isoreticular crystalline hydrazide-based COF photocatalysts, with the optoelectronic properties local pore characteristics COFs modulated using different linkers. The excited state electronic distribution transport pathways in are probed host experimental methods theoretical calculations at molecular level. One our developed (denoted as COF-4) exhibits remarkable electron utilization efficiency charge transfer properties, achieving record-high uranium extraction performance ~6.84 mg/g/day natural seawater among all techniques reported so far. This study brings new understanding operation COF-based guiding design improved photocatalysts for many applications.

Language: Английский

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A Crystalline Partially Fluorinated Triazine Covalent Organic Framework for Efficient Photosynthesis of Hydrogen Peroxide

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(19)

Published: March 1, 2022

A partially fluorinated, metal-free, imine-linked two-dimensional triazine covalent organic framework (TF50 -COF) photocatalyst was developed. Fluorine (F)-substituted and nonsubstituted units were integrated in equimolar amounts on the edge aromatic units, where they mediated two-electron O2 photoreduction. F-substitution created an abundance of Lewis acid sites, which regulated electronic distribution adjacent carbon atoms provided highly active sites for adsorption, widened visible-light-responsive range catalyst, while enhancing charge separation. Varying proportion F maximized interlayer interactions TF50 -COF, resulting improved crystallinity with faster carrier transfer robust photostability. The -COF catalyst demonstrates high selectivity stability photoreduction into H2 , a yield rate 1739 μmol h-1 g-1 remarkable apparent quantum efficiency 5.1 % at 400 nm, exceeding performance previously reported nonmetal COF-based photocatalysts.

Language: Английский

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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

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Photoinduced Borylation for the Synthesis of Organoboron Compounds

Chemical Reviews, Journal Year: 2021, Volume and Issue: 121(7), P. 3561 - 3597

Published: Feb. 17, 2021

Organoboron compounds have important synthetic value and can be applied in numerous transformations. The development of practical convenient ways to synthesize boronate esters has thus attracted significant interest. Photoinduced borylations originated from stoichiometric reactions alkanes arenes with well-defined metal–boryl complexes. Now, photoredox-initiated borylations, catalyzed by either transition metal or organic photocatalysts, photochemical high efficiency become a burgeoning area research. In this Focus Review, we summarize research on photoinduced especially emphasizing recent developments trends. This includes the borylation arenes, alkanes, aryl/alkyl halides, activated carboxylic acids, amines, alcohols, so based catalysis, metal-free organocatalysis, direct activation. We focus reaction mechanisms involving single-electron transfer, triplet-energy other radical processes.

Language: Английский

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