Thiol-functionalized magnetic covalent organic frameworks by a cutting strategy for efficient removal of Hg2+ from water

Two imine-based covalent organic frameworks with different pore sizes were synthesized, and can be used as adsorbents for the removal of bisphenol pollutants, showing high affinity toward bisphenol S and bisphenol A.

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Rational construction of covalent organic frameworks with multi-site functional groups for highly efficient removal of low-concentration U(vi) from water

Environmental Science Nano ◽

10.1039/d1en00059d ◽

2021 ◽

Author(s):

Tingting Yang ◽

Chen Tian ◽

Xu Yan ◽

Ruiyang Xiao ◽

Zhang Lin

Keyword(s):

Functional Groups ◽

Covalent Organic Frameworks ◽

Efficient Removal ◽

Low Concentration ◽

Highly Efficient ◽

Rational Construction

The multi-site chelation effect has successfully improved the affinity of COF-TpDd-AO2 towards low-concentration uranium.

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Covalent organic frameworks: an ideal platform for designing ordered materials and advanced applications

Chemical Society Reviews ◽

10.1039/d0cs00620c ◽

2021 ◽

Author(s):

Ruoyang Liu ◽

Ke Tian Tan ◽

Yifan Gong ◽

Yongzhi Chen ◽

Zhuoer Li ◽

...

Keyword(s):

Covalent Organic Frameworks ◽

2D And 3D ◽

Advanced Applications

Covalent organic frameworks offer a molecular platform for integrating organic units into periodically ordered yet extended 2D and 3D polymers to create topologically well-defined polygonal lattices and built-in discrete micropores and/or mesopores.

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EFFICIENT REMOVAL OF ANIONIC DYE POLLUTANT BY NIMGAL LAYERED DOUBLE HYDROXIDES OF VARIABLE COMPOSITION

Catalysis in Green Chemistry and Engineering ◽

10.1615/catalgreenchemeng.2018028634 ◽

2018 ◽

Vol 1 (4) ◽

pp. 307-323

Author(s):

Dipshikha Bharali ◽

Pankaj Bharali ◽

Ramesh Ch. Deka

Keyword(s):

Layered Double Hydroxides ◽

Variable Composition ◽

Efficient Removal ◽

Anionic Dye ◽

Double Hydroxides

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Intercalation of First Row Transition Metals inside Covalent-Organic Frameworks (COF): a Strategy to Fine Tune the Electronic Properties of Porous Crystalline Materials

10.26434/chemrxiv.6712826 ◽

2018 ◽

Author(s):

Srimanta Pakhira ◽

Jose Mendoza-Cortes

Keyword(s):

Transition Metal ◽

Transition Metals ◽

Electronic Properties ◽

High Surface ◽

Electronic Devices ◽

High Surface Area ◽

Main Role ◽

Covalent Organic Frameworks ◽

Porous Network ◽

Crystalline Materials

<div>Covalent organic frameworks (COFs) have emerged as an important class of nano-porous crystalline materials with many potential applications. They are intriguing platforms for the design of porous skeletons with special functionality at the molecular level. However, despite their extraordinary properties, it is difficult to control their electronic properties, thus hindering the potential implementation in electronic devices. A new form of nanoporous material, COFs intercalated with first row transition metal is proposed to address this fundamental drawback - the lack of electronic tunability. Using first-principles calculations, we have designed 31 new COF materials <i>in-silico</i> by intercalating all of the first row transition metals (TMs) with boroxine-linked and triazine-linked COFs: COF-TM-x (where TM=Sc-Zn and x=3-5). This is a significant addition considering that only 187 experimentally COFs structures has been reported and characterized so far. We have investigated their structure and electronic properties. Specifically, we predict that COF's band gap and density of states (DOSs) can be controlled by intercalating first row transition metal atoms (TM: Sc - Zn) and fine tuned by the concentration of TMs. We also found that the $d$-subshell electron density of the TMs plays the main role in determining the electronic properties of the COFs. Thus intercalated-COFs provide a new strategy to control the electronic properties of materials within a porous network. This work opens up new avenues for the design of TM-intercalated materials with promising future applications in nanoporous electronic devices, where a high surface area coupled with fine-tuned electronic properties are desired.</div>

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Seeded Growth of Single-Crystal Two-Dimensional Covalent Organic Frameworks

10.26434/chemrxiv.5702437.v2 ◽

2017 ◽

Cited By ~ 1

Author(s):

Austin M. Evans ◽

Lucas R. Parent ◽

Nathan C. Flanders ◽

Ryan P. Bisbey ◽

Edon Vitaku ◽

...

Keyword(s):

Molecular Transport ◽

Controlled Synthesis ◽

Two Dimensional ◽

Covalent Organic Frameworks ◽

Seeded Growth ◽

Covalent Bonds ◽

Crystalline Materials ◽

Step Procedure ◽

Structures And Properties ◽

2D Polymer

<div> <div> <div> <p>Polymerizing monomers into periodic two-dimensional (2D) networks provides structurally precise, atomically thin macromolecular sheets linked by robust, covalent bonds. These materials exhibit desirable mechanical, optoelectrotronic, and molecular transport properties derived from their designed structure and permanent porosity. 2D covalent organic frameworks (COFs) offer broad monomer scope, but are generally isolated as polycrystalline, insoluble powders with limited processability. Here we overcome this limitation by controlling 2D COF formation using a two- step procedure. In the first step, 2D COF nanoparticle seeds are prepared with approximate diameters of 30 nm. Next, monomers are slowly added to suppress new nucleation while promoting epitaxial growth on the existing seeds to sizes of several microns. The resulting COF nanoparticles are of exceptional and unprecedented quality, isolated as single crystalline materials with micron-scale domain sizes. These findings advance the controlled synthesis of 2D layered COFs and will enable a broad exploration of synthetic 2D polymer structures and properties. </p> </div> </div> </div>

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