Detailed total scattering analysis of disorder in ZIF-8

2021 ◽  
Vol 54 (3) ◽  
Author(s):  
Peter C. Metz ◽  
Stephen C. Purdy ◽  
Matthew R. Ryder ◽  
Arvind Ganesan ◽  
Sankar Nair ◽  
...  
Keyword(s):  
Density Functional ◽  
Elastic Anisotropy ◽  
Metal Organic Framework ◽  
Rietveld Analysis ◽  
Zeolitic Imidazolate Framework ◽  
Cubic Lattice ◽  
Framework Materials ◽  
Metal Organic ◽  
Experimental Pair ◽  
Metal Sublattices

This work investigates the X-ray scattering signatures of disorder in the zeolitic imidazolate framework ZIF-8. Two layer disorder models are examined in reciprocal space and compared with conventional Rietveld analysis. Stacking faults along the [001] direction of the cubic lattice are in poor agreement with experimental powder diffraction data, consistent with previously reported density functional theory studies showing that these defects are energetically unfavorable compared with amorphization. Meanwhile, fluctuation of layer position along the [110] direction of the cubic lattice shows a significant agreement with experimental data. This result is interpreted analogously to an anisotropic strain mechanism, suggesting links between elastic anisotropy and crystallographic imperfections found in metal–organic framework materials. In direct space, it is demonstrated that models accounting for the static position disorder amongst the linker and metal sublattices are required to fit the experimental pair distribution function data.

Novel metal–organic framework materials: blends, liquids, glasses and crystal–glass composites

2019 ◽  
Vol 55 (60) ◽  
pp. 8705-8715 ◽  
Author(s):  
Joshua M. Tuffnell ◽  
Christopher W. Ashling ◽  
Jingwei Hou ◽  
Shichun Li ◽  
Louis Longley ◽  
...  
Keyword(s):  
Metal Organic Framework ◽  
Metal Organic Frameworks ◽  
Crystal Glass ◽  
Zeolitic Imidazolate Framework ◽  
Feature Article ◽  
Glass Composites ◽  
Framework Materials ◽  
Recent Advances ◽  
Metal Organic ◽  
Organic Framework

This Feature Article reviews a range of amorphisation mechanisms of Metal–Organic Frameworks (MOFs) and presents recent advances to produce novel MOF materials including porous MOF glasses, MOF crystal–glass composites, flux melted MOF glasses and blended zeolitic imidazolate framework glasses.

Two methods for constructing ZIF-8 nanomaterials with good bio compatibility and robust antibacterial applied to biomedical

2021 ◽  
pp. 088532822110336
Author(s):  
Ying Zhang ◽  
Ting-Ting Li ◽  
Bing-Chiuan Shiu ◽  
Jia-Horng Lin ◽  
Ching-Wen Lou
Keyword(s):  
Metal Organic Framework ◽  
Antibacterial Properties ◽  
Functional Materials ◽  
Hexagonal Structure ◽  
Practical Significance ◽  
Zeolitic Imidazolate Framework ◽  
Solvent Method ◽  
Framework Materials ◽  
Metal Organic ◽  
Organic Framework

Metal-organic framework materials not only possess porous structures, but also have excellent antibacterial properties. It is of great practical significance to prepare new antibacterial materials with excellent antibacterial effect by metal-organic framework materials. In our study, Zeolitic Imidazolate Framework-8 (ZIF-8) nanomaterials with antibacterial properties were prepared via the solvent method and diethanolamine template method. The materials were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), cold field-emission scanning electron microscope (SEM), transmission electron microscopy (TEM), N2 adsorption-desorption experiment, antibacterial experiment, and biocompatibility experiment. Results showed that ZIF-8 prepared by solvent method has a more typical hexagonal structure, larger specific surface area, and smaller pore size, and the values are 1812.07 m2g−1 and 2.2412 nm, respectively. At the same time, the materials prepared by the two methods have excellent antibacterial properties, and exhibit good biocompatibility at low concentrations, the antibacterial activity against Escherichia coli and Staphylococcus aureus are higher than 95%, and the cell viabilities of the selected five material concentrations of 12.5 µg mL−1, 25 µg mL−1, 50 µg mL−1, 100 µg mL−1 and 200 µg mL−1 are more than 70%. Therefore, this study provides a feasible method for preparing Nano-scale antibacterial functional particles, and it is of great significance to broaden the application field of ZIF-8 materials and prepare ZIF-8 drug-delivery functional materials.

scholarly journals Three-step nucleation of metal–organic framework nanocrystals

2021 ◽  
Vol 118 (10) ◽  
pp. e2008880118
Author(s):  
Xiangwen Liu ◽  
See Wee Chee ◽  
Sanoj Raj ◽  
Michal Sawczyk ◽  
Petr Král ◽  
...  
Keyword(s):  
Liquid Phase ◽  
Metal Organic Framework ◽  
Precursor Solution ◽  
Industrial Applications ◽  
Growth Stages ◽  
Zeolitic Imidazolate Framework ◽  
Framework Materials ◽  
Design And Synthesis ◽  
Wide Range ◽  
Metal Organic

Metal–organic frameworks (MOFs) are crystalline nanoporous materials with great potential for a wide range of industrial applications. Understanding the nucleation and early growth stages of these materials from a solution is critical for their design and synthesis. Despite their importance, the pathways through which MOFs nucleate are largely unknown. Using a combination of in situ liquid-phase and cryogenic transmission electron microscopy, we show that zeolitic imidazolate framework-8 MOF nanocrystals nucleate from precursor solution via three distinct steps: 1) liquid–liquid phase separation into solute-rich and solute-poor regions, followed by 2) direct condensation of the solute-rich region into an amorphous aggregate and 3) crystallization of the aggregate into a MOF. The three-step pathway for MOF nucleation shown here cannot be accounted for by conventional nucleation models and provides direct evidence for the nonclassical nucleation pathways in open-framework materials, suggesting that a solute-rich phase is a common precursor for crystallization from a solution.

scholarly journals Size-Controllable Synthesis of Zeolitic Imidazolate Framework/Carbon Nanotube Composites

Crystals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 367 ◽  
Author(s):  
Fang Fu ◽  
Bin Zheng ◽  
Lin-Hua Xie ◽  
Huiling Du ◽  
Shuangming Du ◽  
...  
Keyword(s):  
Composite Materials ◽  
Density Functional ◽  
Metal Organic Framework ◽  
Zeolitic Imidazolate Frameworks ◽  
Controllable Synthesis ◽  
Zeolitic Imidazolate Framework ◽  
Nanotube Composites ◽  
Metal Organic ◽  
Micrometer Size ◽  
Novel Applications

Composite materials that combine the unique properties of zeolitic imidazolate frameworks (ZIFs) and carbon nanotubes (CNTs) can give rise to novel applications. Here, ZIF-8/CNT composites were successfully prepared with and without the addition of an agent template. The size of the ZIF-8 crystals in the composite materials was controlled by varying the template, feeding order, and concentration of reactants. Thus, ZIF-8 crystals with a wide variety of sizes (from nano- to micrometer size, which is range that differs by a factor of 10) were obtained, depending on the conditions. This size-controllable synthesis of ZIF-8 was achieved by modifying the number of nucleation sites on the CNTs, as revealed by density functional theory (DFT) calculations. This work provides an efficient method for preparing ZIF-8/CNT composites with controllable size and can pave the way for the synthesis of other metal-organic framework (MOF)/CNT composite materials.

scholarly journals Selective capture of carbon dioxide from hydrocarbons using a metal-organic framework

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Omid T. Qazvini ◽  
Ravichandar Babarao ◽  
Shane G. Telfer
Keyword(s):  
Carbon Dioxide ◽  
Density Functional ◽  
Metal Organic Framework ◽  
Density Functional Theory Calculations ◽  
Time Lags ◽  
X Ray Crystallography ◽  
Metal Organic ◽  
Adsorption Of Co ◽  
Short Time ◽  
Organic Framework

AbstractEfficient and sustainable methods for carbon dioxide capture are highly sought after. Mature technologies involve chemical reactions that absorb CO2, but they have many drawbacks. Energy-efficient alternatives may be realised by porous physisorbents with void spaces that are complementary in size and electrostatic potential to molecular CO2. Here, we present a robust, recyclable and inexpensive adsorbent termed MUF-16. This metal-organic framework captures CO2 with a high affinity in its one-dimensional channels, as determined by adsorption isotherms, X-ray crystallography and density-functional theory calculations. Its low affinity for other competing gases delivers high selectivity for the adsorption of CO2 over methane, acetylene, ethylene, ethane, propylene and propane. For equimolar mixtures of CO2/CH4 and CO2/C2H2, the selectivity is 6690 and 510, respectively. Breakthrough gas separations under dynamic conditions benefit from short time lags in the elution of the weakly-adsorbed component to deliver high-purity hydrocarbon products, including pure methane and acetylene.

scholarly journals Templated interfacial synthesis of metal-organic framework (MOF) nano- and micro-structures with precisely controlled shapes and sizes

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Lingyao Meng ◽  
Binyu Yu ◽  
Yang Qin
Keyword(s):  
Crystal Growth ◽  
Metal Organic Framework ◽  
Reaction Conditions ◽  
Zeolitic Imidazolate Framework ◽  
Crystallographic Preferred Orientation ◽  
Metal Organic ◽  
Interfacial Synthesis ◽  
Oil Water ◽  
Synthesis Methodology ◽  
Micro Structures

AbstractMetal-organic frameworks (MOF) are an emerging class of microporous materials with promising applications. MOF nanocrystals, and their assembled super-structures, can display unique properties and reactivities when compared with their bulk analogues. MOF nanostructures of 0-D, 2-D, and 3-D dimensions can be routinely obtained by controlling reaction conditions and ligand additives, while formation of 1-D MOF nanocrystals (nanowires and nanorods) and super-structures has been relatively rare. We report here a facile templated interfacial synthesis methodology for the preparation of a series of 1-D MOF nano- and micro-structures with precisely controlled shapes and sizes. Specifically, by applying track-etched polycarbonate (PCTE) membranes as the templates and at the oil/water interface, we rapidly and reproducibly synthesize zeolitic imidazolate framework-8 (ZIF-8) and ZIF-67 nano- and micro structures of sizes ranging from 10 nm to 20 μm. We also identify a size confinement effect on MOF crystal growth, which leads to single crystals under the most restricted conditions and inter-grown polycrystals at larger template pore sizes, as well as surface directing effects that influence the crystallographic preferred orientation. Our findings provide a potentially generalizable method for controlling the size, morphology, and crystal orientations of MOF nanomaterials, as well as offering fundamental understanding into MOF crystal growth mechanisms.

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