Mechanochemical Synthesis of a Mercury(II) Metal-Organic Framework Reveals a Two-Dimensional Polymorph Stabilized by Weak Interactions

Solid-state mechanochemistry revealed a novel polymorph of the mercury(II) imidazolate framework, based on square-grid (sql) topology layers. Reaction monitoring and periodic density functional theory calculations show that the sql-structure is of higher stability than the previously reported three-dimensional structure, with the unexpected stabilization of a lower dimensionality structure explained by contributions of weak interactions, which include short C-H···Hg contacts.

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Exposing unsaturated Cu1-O2 sites in nanoscale Cu-MOF for efficient electrocatalytic hydrogen evolution

Science Advances ◽

10.1126/sciadv.abg2580 ◽

2021 ◽

Vol 7 (18) ◽

pp. eabg2580

Author(s):

Weiren Cheng ◽

Huabin Zhang ◽

Deyan Luan ◽

Xiong Wen (David) Lou

Keyword(s):

Hydrogen Evolution ◽

Density Functional ◽

Metal Organic Framework ◽

Density Functional Theory Calculations ◽

Active Centers ◽

Functional Theory ◽

Hollow Nanostructure ◽

Metal Organic ◽

X Ray Absorption ◽

A Current

Conductive metal-organic framework (MOF) materials have been recently considered as effective electrocatalysts. However, they usually suffer from two major drawbacks, poor electrochemical stability and low electrocatalytic activity in bulk form. Here, we have developed a rational strategy to fabricate a promising electrocatalyst composed of a nanoscale conductive copper-based MOF (Cu-MOF) layer fully supported over synergetic iron hydr(oxy)oxide [Fe(OH)x] nanoboxes. Owing to the highly exposed active centers, enhanced charge transfer, and robust hollow nanostructure, the obtained Fe(OH)x@Cu-MOF nanoboxes exhibit superior activity and stability for the electrocatalytic hydrogen evolution reaction (HER). Specifically, it needs an overpotential of 112 mV to reach a current density of 10 mA cm−2 with a small Tafel slope of 76 mV dec−1. X-ray absorption fine structure spectroscopy combined with density functional theory calculations unravels that the highly exposed coordinatively unsaturated Cu1-O2 centers could effectively accelerate the formation of key *H intermediates toward fast HER kinetics.

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Two-dimensional metal-organic frameworks Mo3(C2O)12 as promising single-atom catalysts for selective nitrogen-to-ammonia

Journal of Materials Chemistry A ◽

10.1039/d1ta07613b ◽

2022 ◽

Author(s):

Zhen Feng ◽

Zelin Yang ◽

Xiaowen Meng ◽

Fachuang Li ◽

Zhanyong Guo ◽

...

Keyword(s):

Density Functional Theory ◽

Density Functional ◽

Metal Organic Frameworks ◽

Density Functional Theory Calculations ◽

Reduction Reaction ◽

Single Atom ◽

Two Dimensional ◽

Functional Theory ◽

New Family ◽

Metal Organic

The development of single-atom catalysts (SACs) for electrocatalytic nitrogen reduction reaction (NRR) remains a great challenge. Using density functional theory calculations, we design a new family of two-dimensional metal-organic frameworks...

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Characterization and gas adsorption of a novel three-dimensional metal–organic framework (MOF) generated from a new polydentate fluorene-bridged ligand

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229618000815 ◽

2018 ◽

Vol 74 (2) ◽

pp. 212-217 ◽

Cited By ~ 1

Author(s):

Shu-Ying Han ◽

Xue Niu ◽

Jia Wang ◽

Guo-Xia Jin ◽

Ai Liu ◽

...

Keyword(s):

Gas Adsorption ◽

Metal Organic Framework ◽

Three Dimensional ◽

Dimensional Structure ◽

Solvothermal Reaction ◽

Two Dimensional ◽

Polydentate Ligand ◽

Dimensional Network ◽

Metal Organic ◽

Organic Framework

A polydentate ligand bridged by a fluorene group, namely 9,9-bis(2-hydroxyethyl)-2,7-bis(pyridin-4-yl)fluorene (L), has been prepared under solvothermal conditions in acetonitrile. Crystals of the three-dimensional metal–organic framework (MOF) poly[[[μ3-9,9-bis(2-hydroxyethyl)-2,7-bis(pyridin-4-yl)fluorene-κ3 N:N′:O]bis(methanol-κO)(μ-sulfato-κ2 O:O′)nickel(II)] methanol disolvate], {[Ni(SO4)(C27H24N2O2)(CH3OH)]·2CH3OH} n , (I), were obtained by the solvothermal reaction of L and NiSO4 in methanol. The ligand L forms a two-dimensional network in the crystallographic bc plane via two groups of O—H...N hydrogen bonds and neighbouring two-dimensional planes are completely parallel and stack to form a three-dimensional structure. In (I), the NiII ions are linked by sulfate ions through Ni—O bonds to form inorganic chains and these Ni-containing chains are linked into a three-dimensional framework via Ni—O and Ni—N bonds involving the polydentate ligand L. With one of the hydroxy groups of L coordinating to the NiII atom, the torsion angle of the hydroxyethyl group changes from that of the uncoordinated molecule. In addition, the adsorption properties of (I) with carbon dioxide were investigated.

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Molecular Rh(III) and Ir(III) Catalysts Immobilized on Bipyridine-Based Covalent Triazine Frameworks for the Hydrogenation of CO2 to Formate

Catalysts ◽

10.3390/catal8070295 ◽

2018 ◽

Vol 8 (7) ◽

pp. 295 ◽

Cited By ~ 13

Author(s):

Gunniya Gunasekar ◽

Kwangho Park ◽

Hyeonseok Jeong ◽

Kwang-Deog Jung ◽

Kiyoung Park ◽

...

Keyword(s):

Density Functional ◽

Three Dimensional ◽

Catalytic Efficiency ◽

Density Functional Theory Calculations ◽

Catalyst Design ◽

Two Dimensional ◽

Functional Theory ◽

Hydrogenation Of Co2 ◽

Catalytic Reactivity ◽

Reduced Activity

The catalytic reactivity of molecular Rh(III)/Ir(III) catalysts immobilized on two- and three-dimensional Bipyridine-based Covalent Triazine Frameworks (bpy-CTF) for the hydrogenation of CO2 to formate has been described. The heterogenized Ir complex demonstrated superior catalytic efficiency over its Rh counterpart. The Ir catalyst immobilized on two-dimensional bpy-CTF showed an improved turnover frequency and turnover number compared to its three-dimensional counterpart. The two-dimensional Ir catalyst produced a maximum formate concentration of 1.8 M and maintained its catalytic efficiency over five consecutive runs with an average of 92% in each cycle. The reduced activity after recycling was studied by density functional theory calculations, and a plausible leaching pathway along with a rational catalyst design guidance have been proposed.

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Density-functional theory models of Fe(iv)O reactivity in metal–organic frameworks: self-interaction error, spin delocalisation and the role of hybrid exchange

Physical Chemistry Chemical Physics ◽

10.1039/d0cp01285h ◽

2020 ◽

Vol 22 (22) ◽

pp. 12821-12830

Author(s):

Fernan Saiz ◽

Leonardo Bernasconi

Keyword(s):

Density Functional Theory ◽

Oxidation Reaction ◽

Density Functional ◽

Metal Organic Framework ◽

Metal Organic Frameworks ◽

Density Functional Theory Calculations ◽

Functional Theory ◽

Metal Organic ◽

Organic Framework

We study the reactivity of Fe(iv)O moieties supported by a metal–organic framework (MOF-74) in the oxidation reaction of methane to methanol using all-electron, periodic density-functional theory calculations.

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Investigation of Charge-Transfer Interactions Induced by Encapsulating Fullerene in a Mesoporous Tetrathiafulvalene-Based Metal-Organic Framework

10.26434/chemrxiv.8427047.v1 ◽

2019 ◽

Cited By ~ 1

Author(s):

Manuel Souto ◽

Joaquín Calbo ◽

Samuel Mañas-Valero ◽

Aron Walsh ◽

Guillermo Minguez Espallargas

Keyword(s):

Electrical Conductivity ◽

Charge Transfer ◽

Density Functional ◽

Metal Organic Framework ◽

Metal Organic Frameworks ◽

Density Functional Theory Calculations ◽

Spectroscopic Techniques ◽

Functional Theory ◽

Guest Molecules ◽

Metal Organic

The design of Metal-Organic Frameworks (MOFs) incorporating electroactive guest molecules in the pores has become a subject of great interest in order to install additional electrical functionalities within the framework while maintaining porosity. In this direction, understanding the charge-transfer (CT) process between the framework and the guest molecules is crucial towards the design of new electroactive MOFs. Herein, we present the encapsulation of fullerenes (C60) in a mesoporous tetrathiafulvalene(TTF)-based MOF. The CT process between the electron-acceptor C60 guest and the electron-donor TTF ligand is studied in detail by means of different spectroscopic techniques and density functional theory calculations. Importantly, gas sorption measurements demonstrate that sorption capacity is maintained after encapsulation of fullerenes, whereas the electrical conductivity is increased by two orders of magnitude due to the CT interactions between C60and the TTF-based framework.

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Understanding the origins of metal–organic framework/polymer compatibility

Chemical Science ◽

10.1039/c7sc04152g ◽

2018 ◽

Vol 9 (2) ◽

pp. 315-324 ◽

Cited By ~ 78

Author(s):

R. Semino ◽

J. C. Moreton ◽

N. A. Ramsahye ◽

S. M. Cohen ◽

G. Maurin

Keyword(s):

Density Functional ◽

Metal Organic Framework ◽

Metal Organic Frameworks ◽

Density Functional Theory Calculations ◽

Functional Theory ◽

Interfacial Structures ◽

Metal Organic ◽

Polymer Compatibility ◽

Computational Methodology ◽

Dynamics Simulations

The microscopic interfacial structures for a series of metal–organic frameworks (MOFs)/polymer composites consisting of the Zr-based UiO-66 coupled with different polymers are systematically explored by applying a computational methodology that integrates density functional theory calculations and force field-based molecular dynamics simulations.

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Investigation of Charge-Transfer Interactions Induced by Encapsulating Fullerene in a Mesoporous Tetrathiafulvalene-Based Metal-Organic Framework

10.26434/chemrxiv.8427047 ◽

2019 ◽

Author(s):

Manuel Souto ◽

Joaquín Calbo ◽

Samuel Mañas-Valero ◽

Aron Walsh ◽

Guillermo Minguez Espallargas

Keyword(s):

Electrical Conductivity ◽

Charge Transfer ◽

Density Functional ◽

Metal Organic Framework ◽

Metal Organic Frameworks ◽

Density Functional Theory Calculations ◽

Spectroscopic Techniques ◽

Functional Theory ◽

Guest Molecules ◽

Metal Organic

The design of Metal-Organic Frameworks (MOFs) incorporating electroactive guest molecules in the pores has become a subject of great interest in order to install additional electrical functionalities within the framework while maintaining porosity. In this direction, understanding the charge-transfer (CT) process between the framework and the guest molecules is crucial towards the design of new electroactive MOFs. Herein, we present the encapsulation of fullerenes (C60) in a mesoporous tetrathiafulvalene(TTF)-based MOF. The CT process between the electron-acceptor C60 guest and the electron-donor TTF ligand is studied in detail by means of different spectroscopic techniques and density functional theory calculations. Importantly, gas sorption measurements demonstrate that sorption capacity is maintained after encapsulation of fullerenes, whereas the electrical conductivity is increased by two orders of magnitude due to the CT interactions between C60and the TTF-based framework.

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Conductive two-dimensional M3(C6S3O3)2 monolayers as effective electrocatalysts for oxygen reduction reaction

Journal of Materials Chemistry A ◽

10.1039/d1ta07442c ◽

2021 ◽

Author(s):

Tianchun Li ◽

Manman Li ◽

Xinyue Zhu ◽

Juan Zhang ◽

Yu Jing

Keyword(s):

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Density Functional ◽

Metal Organic Frameworks ◽

Density Functional Theory Calculations ◽

Reduction Reaction ◽

Single Atom ◽

Two Dimensional ◽

Functional Theory ◽

Metal Organic

Two dimensional (2D) conjugated metal organic frameworks (MOFs) which feature single atom catalysts are promising electrocatalysts to promote oxygen reduction reaction (ORR). Here, by means of density functional theory calculations...

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