Stable Covalent Organic Frameworks for Exceptional Mercury Removal from Aqueous Solutions

Journal of the American Chemical Society, Год журнала: 2017, Номер 139(6), С. 2428 - 2434

Опубликована: Янв. 25, 2017

The pre-designable porous structures found in covalent organic frameworks (COFs) render them attractive as a molecular platform for addressing environmental issues such removal of toxic heavy metal ions from water. However, rational structural design COFs this aspect has not been explored. Here we report the stable Hg(II) through elaborate and control over skeleton, pore size, walls. resulting framework is under strong acid base conditions, possesses high surface area, large mesopores, contains dense sulfide functional termini on These features work together removing water achieve benchmark system that combines capacity, efficiency, effectivity, applicability, selectivity, reusability. results suggest offer powerful tailor-made to cope with various types pollution.

Язык: Английский

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Designed Synthesis of a 2D Porphyrin‐Based sp²Carbon‐Conjugated Covalent Organic Framework for Heterogeneous Photocatalysis

Angewandte Chemie International Edition, Год журнала: 2019, Номер 58(19), С. 6430 - 6434

Опубликована: Март 19, 2019

The construction of stable covalent organic frameworks (COFs) for various applications is highly desirable. Herein, we report the synthesis a novel two-dimensional (2D) porphyrin-based sp2 carbon-conjugated COF (Por-sp2 c-COF), which adopts an eclipsed AA stacking structure with Brunauer-Emmett-Teller surface area 689 m2 g-1 . Owing to C=C linkages, Por-sp2 c-COF shows high chemical stability under conditions, even harsh conditions such as 9 m HCl and NaOH solutions. Interestingly, can be used metal-free heterogeneous photocatalyst visible-light-induced aerobic oxidation amines imines. More importantly, in comparison imine-linked Por-COF, inherent equips it several advantages photocatalyst, including reusability photocatalytic performance. This clearly demonstrates that carbon-linked 2D COFs provide interesting platform photocatalysis.

Язык: Английский

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Synthesis of Ultrafine and Highly Dispersed Metal Nanoparticles Confined in a Thioether-Containing Covalent Organic Framework and Their Catalytic Applications

Journal of the American Chemical Society, Год журнала: 2017, Номер 139(47), С. 17082 - 17088

Опубликована: Ноя. 3, 2017

Covalent organic frameworks (COFs) with well-defined and customizable pore structures are promising templates for the synthesis of nanomaterials controllable sizes dispersity. Herein, a thioether-containing COF has been rationally designed used confined growth ultrafine metal nanoparticles (NPs). Pt or Pd (Pt NPs NPs) immobilized inside cavity material have successfully prepared at high loading narrow size distribution (1.7 ± 0.2 nm). We found crystallinity support presence thioether groups cavities critical size-controlled NPs. The as-prepared COF-supported show excellent catalytic activity respectively in nitrophenol reduction Suzuki-Miyaura coupling reaction under mild conditions low catalyst loading. More importantly, they highly stable easily recycled reused without loss their activities. Such will open new frontier on design preparation NP@COF composite materials various potential applications, such as catalysis development optical electronic materials.

Язык: Английский

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2D Covalent Organic Frameworks as Intrinsic Photocatalysts for Visible Light-Driven CO₂ Reduction

Journal of the American Chemical Society, Год журнала: 2018, Номер 140(44), С. 14614 - 14618

Опубликована: Окт. 24, 2018

Covalent organic framework (COF) represents an emerging class of porous materials that have exhibited great potential in various applications, particularly catalysis. In this work, we report a newly designed 2D COF with incorporated Re complex, which exhibits intrinsic light absorption and charge separation (CS) properties. We show hybrid catalyst can efficiently reduce CO2 to form CO under visible illumination high electivity (98%) better activity than its homogeneous counterpart. More importantly, using advanced transient optical X-ray spectroscopy situ diffuse reflectance spectroscopy, unraveled three key intermediates are responsible for CS, the induction period, rate limiting step This work not only demonstrates COFs as next generation photocatalysts solar fuel conversion but also provide unprecedented insight into mechanistic origins light-driven reduction.

Язык: Английский

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

The Innovation, Год журнала: 2021, Номер 2(1), С. 100076 - 100076

Опубликована: Янв. 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.

Язык: Английский

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Regenerable and stable sp2 carbon-conjugated covalent organic frameworks for selective detection and extraction of uranium

Nature Communications, Год журнала: 2020, Номер 11(1)

Опубликована: Янв. 23, 2020

Abstract Uranium is a key element in the nuclear industry, but its unintended leakage has caused health and environmental concerns. Here we report sp 2 carbon-conjugated fluorescent covalent organic framework (COF) named TFPT-BTAN-AO with excellent chemical, thermal radiation stability synthesized by integrating triazine-based building blocks amidoxime-substituted linkers. shows an exceptional UO 2+ adsorption capacity of 427 mg g −1 attributable to abundant selective uranium-binding groups on highly accessible pore walls open 1D channels. In addition, it ultra-fast response time (2 s) ultra-low detection limit 6.7 nM suitable for on-site real-time monitoring , allowing not only extraction also quality extracted water. This study demonstrates great potential COFs radionuclide extraction. By rational designing target ligands, this strategy can be extended other contaminants.

Язык: Английский

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Covalent organic frameworks (COFs) for environmental applications

Coordination Chemistry Reviews, Год журнала: 2019, Номер 400, С. 213046 - 213046

Опубликована: Сен. 11, 2019

Язык: Английский

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Opportunities of Covalent Organic Frameworks for Advanced Applications

Advanced Science, Год журнала: 2018, Номер 6(2)

Опубликована: Ноя. 12, 2018

Abstract Covalent organic frameworks (COFs) are an emerging class of functional nanostructures with intriguing properties, due to their unprecedented combination high crystallinity, tunable pore size, large surface area, and unique molecular architecture. The range properties characterized in COFs has rapidly expanded include those interest for numerous applications ranging from energy environment. Here, a background overview is provided, consisting brief introduction porous materials the design feature COFs. Then, recent advancements as designer platform plethora emphasized together discussions about strategies principles involved. Finally, challenges remaining this type material real outlined.

Язык: Английский

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Covalent Organic Frameworks: Chemical Approaches to Designer Structures and Built‐In Functions

Angewandte Chemie International Edition, Год журнала: 2019, Номер 59(13), С. 5050 - 5091

Опубликована: Май 30, 2019

Abstract A new approach has been developed to design organic polymers using topology diagrams. This strategy enables covalent integration of units into ordered topologies and creates a polymer form, that is, frameworks. is breakthrough in chemistry because it sets molecular platform for synthesizing with predesignable primary high‐order structures, which central aim over century but unattainable traditional principles. field its own features are distinct from conventional polymers. Review summarizes the fundamentals as well major progress by focusing on used including principles, synthetic strategies, control methods. We scrutinize built‐in functions specific structures revealing various interplays mechanisms involved expression function. propose fundamental issues be addressed future directions physics, materials, application perspectives.

Язык: Английский

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Covalent Organic Frameworks and Cage Compounds: Design and Applications of Polymeric and Discrete Organic Scaffolds

Angewandte Chemie International Edition, Год журнала: 2017, Номер 57(18), С. 4850 - 4878

Опубликована: Дек. 5, 2017

Porous organic materials are an emerging class of functional nanostructures with unprecedented properties. Dynamic covalent assembly small building blocks under thermodynamic control is utilized for the intriguingly simple formation complex molecular architectures in one-pot procedures. In this Review, we aim to analyze basic design principles that govern either frameworks as crystalline porous polymers or cage compounds shape-persistent objects. Common synthetic procedures and characterization techniques will be discussed well more advanced strategies such postsynthetic modification self-sorting. When appropriate, comparisons drawn between polymeric discrete cages terms their underlying Furthermore, highlight potential these applications ranging from gas storage catalysis electronics.

Язык: Английский

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