Hydrothermal Synthesis and Characterization of a Metal–Organic Framework by Thermogravimetric Analysis, Powder X-ray Diffraction, and Infrared Spectroscopy: An Integrative Inorganic Chemistry Experiment

2014 ◽  
Vol 92 (2) ◽  
pp. 373-377 ◽  
Author(s):  
Johanna L. Crane ◽  
Kelly E. Anderson ◽  
Samantha G. Conway
2021 ◽  
Vol 12 (1) ◽  
pp. 52
Author(s):  
Arslan Munir ◽  
Ali Ahmad ◽  
Muhammad Tahseen Sadiq ◽  
Ali Sarosh ◽  
Ghulam Abbas ◽  
...  

Recent development shows that carbon-based composites are proving to be the most promising materials in hydrogen energy production, storage and conversion applications. In this study, composites of the copper-based metal-organic framework with different ratios of graphite oxide have been prepared for hydrogen storage application. The developed materials are characterized by X-ray diffraction (XRD), gravimetric thermal analysis (TGA), scanning electron microscopy (SEM) and BET. The newly developed composites have an improved crystalline structure and an increased surface area. The results of the experiment showed that the composite material MOF/GO 20% can store 6.12% of hydrogen at −40 °C.


2014 ◽  
Vol 976 ◽  
pp. 164-168 ◽  
Author(s):  
Nayely Torres-Gomez ◽  
Alfredo R. Vilchis-Nestor ◽  
Rosa Maria Gomez-Espinosa ◽  
Ivan Garcia-Orozco

Copper complexes of dithiocarbamates ligands were obtained from RNH2 (R = C6H13-, C12H25- y C18H37-) and an excess of CS2 in the presence of NaOH. Sodium hexyldithiocarbamate is not possible to isolate from solution but the other two were obtained and characterizedby infrared spectroscopy, UV-vis and powder X-ray diffraction. Copper complexes were obtained in situ from ligand solution as greenish powders. All the complexes were characterized by infrared spectroscopy, UV-vis, powder X-ray diffraction and Scanning Electron Microscopy. The complexes show an amorphous phase in the case of DCu12 and nanocrystalline structure for DCu18, as observed in XRD.


2019 ◽  
Author(s):  
Christopher A. O’Keefe ◽  
Cristina Mottillo ◽  
László Fábián ◽  
Tomislav Friscic ◽  
Robert W. Schurko

NMR-enhanced crystallography enables the characterization of a novel cadmium-based, open metal-organic framework (MOF) from a solvent-free "accelerated aging" process. Whereas accelerated aging was devised as a clean, mild route for making MOFs, these results highlight how it application in materials discovery and characterization is aided by a combination of X-ray diffraction and solid-state NMR spectroscopy.<br>


Crystals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 466
Author(s):  
Loisangela Álvarez ◽  
Blanca Rojas de Gascue ◽  
Rolando J. Tremont ◽  
Edgar Márquez ◽  
Euclides J. Velazco

A new compound, Bi2O2CO3:Al, was synthesized by the coprecipitation method. The characterization was done by X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), electronic scanning microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX). The characterization methods allowed to identify the Bi2O2CO3:Al compound, such as the Al-doped Bi2O2CO3 by XRD, the anionic part (CO32−) by FTIR, and the presence of aluminum in the compound by XPS and EDX. It was confirmed to have a nanostructure like a nanosheet and a microstructure that resembles a type sponge by SEM.


2012 ◽  
Vol 217-219 ◽  
pp. 551-554
Author(s):  
Ting Xi Li ◽  
Yu Hua Zhao ◽  
Qian Li ◽  
Cheng Qian Yuan ◽  
Quan Liang Chen ◽  
...  

Abstract. Polyaniline (PANI) and p-phenylenediamine (p-PDA)-aniline copolymer were prepared via a same microemulsion method. The structures of the PANI and p-PDA-aniline copolymer were characterized by infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis(TGA). The results revealed the difference of synthesis and characterization between PANI and p-PDA-aniline copolymer. It was shown that structure of the copolymer is almost similar to that of PANI, but the p-PDA-aniline copolymer has a better crystallization than PANI, and the thermal stability of the copolymer is higher than that of pure PANI.


Author(s):  
Naomi Biggins ◽  
Michael Ziebel ◽  
Miguel Gonzalez ◽  
Jeffrey R. Long

<div><p>Precisely locating extra-framework cations in anionic metal–organic framework compounds remains a long-standing, yet crucial, challenge for elucidating structure-performance relationships in functional materials. Single-crystal X-ray diffraction is one of the most powerful approaches for this task, but single crystals of frameworks often degrade when subjected to post-synthetic metalation or reduction. Here, we demonstrate the growth of sizable single crystals of the robust metal–organic framework Fe<sub>2</sub>(bdp)<sub>3</sub> (bdp<sup>2−</sup> = benzene-1,4-dipyrazolate) and employ single-crystal-to-single-crystal chemical reductions to access the solvated framework materials A<sub>2</sub>Fe<sub>2</sub>(bdp)<sub>3</sub>∙<i>y</i>THF<sub> </sub>(A = Li<sup>+</sup>, Na<sup>+</sup>, K<sup>+</sup>). X-ray diffraction analysis of the sodium and potassium congeners reveals that the cations are located near the center of the triangular framework channels and are stabilized by weak cation–π interactions with the framework ligands. Freeze-drying with benzene enables isolation of activated single crystals of Na<sub>0.5</sub>Fe<sub>2</sub>(bdp)<sub>3 </sub>and Li<sub>2</sub>Fe<sub>2</sub>(bdp)<sub>3</sub> and the first structural characterization of activated metal–organic frameworks wherein extra-framework alkali metal cations are also structurally located. Comparison of the solvated and activated sodium-containing structures reveals that the cation positions differ in the two materials, likely due to cation migration that occurs upon solvent removal to maximize stabilizing cation­–π interactions. Hydrogen adsorption data indicate that these cation-framework interactions are sufficient to diminish the effective cationic charge, leading to little or no enhancement in gas uptake relative to Fe<sub>2</sub>(bdp)<sub>3</sub>. In contrast, Mg<sub>0.85</sub>Fe<sub>2</sub>(bdp)<sub>3</sub> exhibits enhanced H<sub>2</sub> affinity and capacity over the non-reduced parent material. This observation shows that increasing the charge density of the pore-residing cation serves to compensate for charge dampening effects resulting from cation–framework interactions and thereby promotes stronger cation–H<sub>2</sub> interactions.</p></div>


2019 ◽  
Author(s):  
Christopher A. O’Keefe ◽  
Cristina Mottillo ◽  
László Fábián ◽  
Tomislav Friscic ◽  
Robert W. Schurko

NMR-enhanced crystallography enables the characterization of a novel cadmium-based, open metal-organic framework (MOF) from a solvent-free "accelerated aging" process. Whereas accelerated aging was devised as a clean, mild route for making MOFs, these results highlight how it application in materials discovery and characterization is aided by a combination of X-ray diffraction and solid-state NMR spectroscopy.<br>


2020 ◽  
Author(s):  
Naomi Biggins ◽  
Michael Ziebel ◽  
Miguel Gonzalez ◽  
Jeffrey R. Long

<div><p>Precisely locating extra-framework cations in anionic metal–organic framework compounds remains a long-standing, yet crucial, challenge for elucidating structure-performance relationships in functional materials. Single-crystal X-ray diffraction is one of the most powerful approaches for this task, but single crystals of frameworks often degrade when subjected to post-synthetic metalation or reduction. Here, we demonstrate the growth of sizable single crystals of the robust metal–organic framework Fe<sub>2</sub>(bdp)<sub>3</sub> (bdp<sup>2−</sup> = benzene-1,4-dipyrazolate) and employ single-crystal-to-single-crystal chemical reductions to access the solvated framework materials A<sub>2</sub>Fe<sub>2</sub>(bdp)<sub>3</sub>∙<i>y</i>THF<sub> </sub>(A = Li<sup>+</sup>, Na<sup>+</sup>, K<sup>+</sup>). X-ray diffraction analysis of the sodium and potassium congeners reveals that the cations are located near the center of the triangular framework channels and are stabilized by weak cation–π interactions with the framework ligands. Freeze-drying with benzene enables isolation of activated single crystals of Na<sub>0.5</sub>Fe<sub>2</sub>(bdp)<sub>3 </sub>and Li<sub>2</sub>Fe<sub>2</sub>(bdp)<sub>3</sub> and the first structural characterization of activated metal–organic frameworks wherein extra-framework alkali metal cations are also structurally located. Comparison of the solvated and activated sodium-containing structures reveals that the cation positions differ in the two materials, likely due to cation migration that occurs upon solvent removal to maximize stabilizing cation­–π interactions. Hydrogen adsorption data indicate that these cation-framework interactions are sufficient to diminish the effective cationic charge, leading to little or no enhancement in gas uptake relative to Fe<sub>2</sub>(bdp)<sub>3</sub>. In contrast, Mg<sub>0.85</sub>Fe<sub>2</sub>(bdp)<sub>3</sub> exhibits enhanced H<sub>2</sub> affinity and capacity over the non-reduced parent material. This observation shows that increasing the charge density of the pore-residing cation serves to compensate for charge dampening effects resulting from cation–framework interactions and thereby promotes stronger cation–H<sub>2</sub> interactions.</p></div>


2013 ◽  
Vol 1576 ◽  
Author(s):  
Jacob Castilow ◽  
Timothy W Zens ◽  
J. Matthew Mann ◽  
Joseph W. Kolis ◽  
Colin D. McMillen ◽  
...  

ABSTRACTHydrothermal synthesis of ThO2, UxTh1-xO2, and UOx at temperatures between 670°C and 700°C has been demonstrated. Synthesis at these temperatures is 50-80°C below prior growth studies and represents a new lower bound of successful growth. ThO2 single crystals of dimensions 6.49mm x 4.89mm x 3.89 mm and weighing 0.633g have been synthesized at average growth rates near 0.125mm/week. Single crystal UxTh1-xO2 crystals with mole fractions up to x≈0.30 have also been grown. The largest alloyed crystal with mole fraction x≈0.23 has dimensions of 2.97mm x 3.23mm x ∼3mm and recorded average growth rates near 0.2mm/week. Four structures were solved from X-ray diffraction data and their crystallographic data reported here. Rocking curve analysis determined a dislocation density of 1.2×109 cm-2.


2017 ◽  
Vol 72 (9) ◽  
pp. 677-685
Author(s):  
Teresa S. Ortner ◽  
Hubert Huppertz

AbstractThe praseodymium borate-nitrate Pr[B5O8(OH)(H2O)0.87]NO3·2H2O was obtained in a hydrothermal synthesis. It crystallizes monoclinically in the space groupP21/n(no. 14) with four formula units (Z=4) and unit cell parameters ofa=641.9(3),b=1551.8(7),c=1068.4(5) pm, withβ=90.54(2)° yieldingV=1.0643(8) nm3. The defect variant constitutes the missing member in the series of isostructural, early rare earth borate-nitrates of the compositionRE[B5O8(OH)(H2O)x]NO3·2H2O [RE=La (x=0; 1), Ce (x=1), Nd (x=0.85), Sm (x=0)]. In addition to powder and single-crystal X-ray diffraction data, the novel borate-nitrate was characterized through IR and Raman spectroscopy.


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