Synthesis and in situ Investigation of Inorganic Organic Hybrid Compounds Based on Metalphosponates and Bismuthcarboxylates

Die hier vorliegende Arbeit beschäftigt sich mit der Synthese und Charakterisierung von neuen anorganisch-organischen Hybridverbindungen und den in situ Untersuchungen ihrer Kristallisation. Den Hauptteil dieser Arbeit machten dabei die Untersuchung polyfunktionalisierter Metallphosphonate und Bismutcarboxylate aus. Die Kristallisationsprozesse wurden mittels energiedispersiver Röntgenbeugung (EDXRD) untersucht. Die Produktbildung von Cu2(O3P-C2H4-SO3(OH)(H2O)2]*3H2O und [Cu2(O3P-C2H4-SO3(OH)(H2O)] verläuft über das metastabile hydratisierte Intermediat [Cu2(O3P-C2H4-SO3(OH)(H2O)2] *4H2O, während bei der Kristallisation von Ca(O3P-C2H4-NH2) das Intermediat [Ca(OH) (O3P-C2H4-NH3)]*2H2O beobachtet wird. Die Kristallstrukturen beider Intermediate und von Ca(O3P-C2H4-NH2) wurden hierbei aus Röntgenpulverdaten bestimmt. EDXRD Untersuchungen der Bildung von M(HO3P-CH2)2-NHCH2-C6H4-COOH (M = Mn2+, Co2+, Fe2+, Ni2+), zeigten verschiedene Reaktionszeiten und Intermediate in Abhängigkeit des Metallions. Die Kristallisation von Sm(O3P-C4H8-SO3)(H2O), Co-CPO-27 und Ni-CPO-27 wurden in situ untersucht und unter Verwendung des Avrami bzw. Gualtieri Modells war es möglich die Geschwindigkeitskonstanten und Arrhenius-Akti\-vierung\-senergien der Reaktionen sowohl unter mikrowellenunterstützten als auch konventionellen Synthesebedingungen zu bestimmen. Mikrowellenunterstütze Synthesemethoden konnten ebenfalls genutzt werden um die Verbindungen [Ni(m-[(HO3PCH2)2NHCH2]2C6H4)] *H2O, [Cd(p-[(HO3PCH2)2NHCH2]2C6H4)] und [Zn(p-[(HO3PCH2)2NHCH2]2C6H4)H2O] zu synthetisieren und ihre Kristallstrukturen konnten mittels Röntgenpulverbeugung bestimmt bzw. aus kristallographischen Zusammenhängen hergeleitet werden. Unter Verwendung von H3BTB und Bi(NO3)3*5H2O war es möglich das erste hoch poröse Bismutcarboxylat Bi(BTB) (H3BTB=1,3,5-Benzoltrisbenzoesäure) herzustellen, welches eine scheinbare spezifische Oberfläche von 1150 m2/g aufweist. Die Verbindung ist für die Hydroxymethylierung von Furan katalytisch aktiv. Die Kristallstruktur wurde aus einer Kombination von Elektronenbeugungsdaten, Rietveld-Verfeinerung und DFT Rechnungen bestimmt. Ebenso wurde zum ersten Mal die Kristallisation von Bismutcarboxylaten in situ untersucht. Es wurde gezeigt, dass in Abhängigkeit der verwendeten Linkermoleküle Pyromellitsäure (H4Pyr), Trimellitsäure (H3Tri) und Trimesinsäure (H3BDC) unter ansonsten ähnlichen Reaktionsbedingungen isolierbare, nicht isolierbare oder gar keine Intermediate bei der Bildung von Bi(HPyr), Bi(Tri)(H2O) und (Bi2(O)(OH)(HBTC)(NO3)) entstehen.This thesis deals with the synthesis and characterization of new inorganic-organic hybrid compounds and the in situ investigations of their crystallization. The main part of this work deals with metalphosphonates and bismuthcarboxylates. The crystallization was investigated by in situ energy dispersive X-ray diffraction (EDXRD). The product formation of [Cu2(O3P-C2H4-SO3(OH)(H2O)2]*3H2O and [Cu2(O3P-C2H4-SO3(OH)(H2O)] proceeds through the metastable hydrated intermediate [Cu2(O3P-C2H4-SO3(OH)(H2O)2]*4H2O, while in the crystallization of Ca(O3P-C2H4-NH2) the intermediate [Ca(OH)(O3P-C2H4-NH3)]*2H2O is observed. The crystal structure of both intermediates and Ca(O3P-C2H4-NH2) were determined from X-ray powder diffraction data. In situ EDXRD investigations of the formation of M(HO3P-CH2)2NHCH2-C6H4-COOH (M = Mn2+, Co2+, Fe2+, Ni2+), Ca(O3P-C2H4-NH2) revealed different reaction times and intermediates depending on the metal ion used. The in situ investigation of the crystallization of Sm(O3P-C4H8-SO3)(H2O), Co-CPO-27 and Ni-CPO-27 allowed the extraction of rate constants and Arrhenius activation energies for the crystallization under microwave-assisted as well as conventional syntheses methods using the model of Avrami and Gualtieri. Microwave-assisted heating was also used to synthetize the compounds [Ni(m-[(HO3PCH2)2NHCH2]2C6H4)] *H2O, [Cd(p-[(HO3PCH2)2NHCH2]2C6H4)] and [Zn(p-[(HO3PCH2)2NH-CH2]2C6H4)H2O]. Their crystal structures were determined from X-ray powder diffraction or derived from crystallographic relations. The use of H3BTB (1,3,5-benzenetrisbenzoicacid) and Bi(NO3)3*5H2O allowed the synthesis of the first highly porous bismuth carboxylate Bi(BTB) with a specific surface area of 1150 m^2/g (BET). The compound is catalytic active in the hydroxymethylation of furan. The crystal structure was determined by a combination of electron diffraction, Rietveld refinement and DFT calculations. In addition in situ EDXRD was employed to investigate the crystallization of bismuth carboxylates for the first time. Depending on the linkermolecule pyromellitic acid (H4Pyr), trimellitic acid (H3Tri) and trimesic acid (H3BDC) under similar reaction intermediates occur that were isolated and fully characterized

A novel bismuth-based metal-organic framework for high volumetric methane and carbon dioxide adsorption

Solvothermal reaction of H4L (L = biphenyl-3,3’,5,5’-tetracarboxylate) and Bi(NO3)3·(H2O)5 in a mixture of DMF/MeCN/H2O in the presence of piperazine and nitric acid at 100 oC for 10 h affords the solvated metal-organic polymer [Bi2(L)1.5(H2O)2]·(DMF)3.5·(H2O)3 (NOTT-220-solv). A single crystal X-ray structure determination confirms that it crystallises in space group P2/c and has a neutral and non-interpenetrated structure comprising binuclear {Bi2} centres bridged by tetracarboxylate ligands. NOTT-220-solv shows a 3,6-connected network having a new framework topology with a {4·62}2{42·65·88}{62·8} point symbol. The desolvated material NOTT-220a shows exceptionally high adsorption uptakes for CH4 and CO2 on a volumetric basis at moderate pressures and temperatures with a CO2 uptake of 553 gL-1 (20 bar, 293 K) with a saturation uptake of 688 gL-1 (1 bar, 195 K). The corresponding CH4 uptake of 165 V(STP)/V (20 bar, 293 K) and 189 V(STP/V) (35 bar, 293 K) is within the top three MOF materials under the same conditions, surpassed only by PCN-14 and Ni-MOF-74 (230 and 190 V(STP)/V 35 Bar, 298 K). The maximum CH4 uptake for NOTT-220a was recorded at 20 bar and 195 K to be 287 V(STP)/V, while H2 uptake of NOTT-220a at 20 bar, 77 K is 42 gL-1. These gas uptakes have been modelled by Grand Canonical Monte Carlo (GCMC) and Density Functional Theory (DFT) calculations, which confirm the experimental data and give insights into the nature of the binding sites of CH4 and CO2 in this porous hybrid material

Fuel purification, Lewis acid and aerobic oxidation catalysis performed by a microporous Co-BTT (BTT3-=1,3,5-benzenetristetrazolate) framework having coordinatively unsaturated sites

[EN] Two isostructural microporous metal-organic frameworks [Co(DMA)(6)](3)[(Co4Cl)(3-)(BTT)(8)(H2O)(12)](2)center dot 12H2O (BTT3- = 1,3,5-benzenetristetrazolate; DMA N,N'-dimethylacetamide) (1) and [Cd(DMF)(6)](3)[(Cd4Cl)(3)(BTT)(8)(H2O)(12)](2)center dot 14H(2)O center dot 4DMF (DMF = N,N'-dimethylformamide) (2) were synthesized under solvothermal conditions. The structures of both compounds were determined by single-crystal X-ray diffraction data. Each compound adopts a porous three-dimensional framework consisting of square-planar [M4Cl](7+) (M2+ = Co, 1; Cd, 2) units interconnected by triangular tritopic BTT3- bridging ligands to give an anionic (3,8)-connected "Moravia" net. Phase purity of the compounds was confirmed by X-ray powder diffraction (XRPD), IR spectroscopy, thermogravimetric (TG) and elemental analysis. TGA and temperature-dependent XRPD (TDXRPD) experiments indicate a moderate thermal stability up to 350 and 300 degrees C, respectively. Guest exchange followed by heating led to microporous solids with coordinatively unsaturated metal sites. These unsaturated metal sites create opportunities in adsorptive and catalytic applications. These have been probed by the selective removal of sulfur compounds from fuel feeds as well as the catalytic ring opening of styrene oxide and the oxidation of several cycloalkanes and benzyl compounds.The Deutsche Forschungsgemeinschaft (DFG, SPP 1362 "Porous Metal-Organic Frameworks" under the grant STO 643/5-2) is gratefully acknowledged for the financial support. The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 228862.Biswas, S.; Maes, M.; Amarajothi, D.; Feyand, M.; De Vos, DE.; García Gómez, H.; Stock, N. (2012). Fuel purification, Lewis acid and aerobic oxidation catalysis performed by a microporous Co-BTT (BTT3-=1,3,5-benzenetristetrazolate) framework having coordinatively unsaturated sites. Journal of Materials Chemistry. 22(20):10200-10209. https://doi.org/10.1039/c2jm15592cS1020010209222

Unravelling surface and interfacial structures of a metal–organic framework by transmission electron microscopy

Metal-organic frameworks (MOFs) are crystalline porous materials with designable topology, porosity and functionality, having promising applications in gas storage and separation, ion conduction and catalysis. It is challenging to observe MOFs with transmission electron microscopy (TEM) due to the extreme instability of MOFs upon electron beam irradiation. Here, we use a direct-detection electron-counting camera to acquire TEM images of the MOF ZIF-8 with an ultralow dose of 4.1 electrons per square ångström to retain the structural integrity. The obtained image involves structural information transferred up to 2.1 Å, allowing the resolution of individual atomic columns of Zn and organic linkers in the framework. Furthermore, TEM reveals important local structural features of ZIF-8 crystals that cannot be identified by diffraction techniques, including armchair-type surface terminations and coherent interfaces between assembled crystals. These observations allow us to understand how ZIF-8 crystals self-assemble and the subsequent influence of interfacial cavities on mass transport of guest molecules

Systematic and In Situ Energy Dispersive X-ray Diffraction Investigations on the Formation of Lanthanide Phosphonatobutanesulfonates: Ln(O3P−C4H8−SO3)(H2O)\mathrm{Ln(O_3P-C_4H_8-SO_3)(H_2O)} (Ln = La-Gd)

Using the flexible linker H(2)O(3)P-C(4)H(8)-SO(3)H (H(3)L) and rare earth ions Ln(3+) (Ln = La, Ce, Pr, Nd, Sm, Eu, Gd) we were able to synthesize the new isostructural inorganic organic hybrid compounds Ln(O(3)P-C(4)H(8)-SO(3))(H(2)O). High-throughput experiments were employed to study the influence of the molar ratios Ln:H(3)L and pH on the product formation. The crystal structure of the compounds Sm(O(3)P-C(4)H(8)-SO(3))(H(2)O) (1) and Pr(O(3)P-C(4)H(8)-SO(3))(H(2)O) (2) were determined by single crystal diffraction. The structures are built up from chains of edge-sharing LnO(8)-polyhedra that are connected by the phosphonate and sulfonate groups into layers. These layers are linked by the -(CH(2))(4)- group to form a three-dimensional framework. The synthesis of compound 1 was scaled up in a conventional oven as well as in a microwave reactor system. A modification of a microwave reactor system allowed its integration into the beamline F3 at HASYLAB, DESY, Hamburg. The crystallization was investigated in situ by means of energy dispersive X-ray diffraction using conventional as well as microwave heating methods applying temperatures varying from 110 to 150 °C. The formation of Sm(O(3)P-C(4)H(8)-SO(3))(H(2)O) takes place in two steps. In the first step a crystalline intermediate was observed, which transforms completely into compound 1. The method by Sharp and Hancock was used to determine the rate constants, reaction exponents, and the Arrhenius activation energy for both reaction steps. Comparing both heating methods, microwave heating leads to fully crystallized reaction product after shorter reaction times, but neither the temperature nor the heating method has significant influence on the induction time