Suchergebnisse

[EN] Different metalorganic lamellar hybrid materials based on associated nanoribbons were synthesized by the use of alkyl-benzyl monocarboxylate spacers, containing alkyl tails with variable lengths, which acted like structural growing inhibitors. These molecular agents were perpendicularly located and coordinated to aluminium nodes in the interlayer space, controlling the separation between individual structure sub-units. The hybrid materials were studied by X-ray diffraction (XRD), chemical and thermogravimetrical analysis (TGA), nuclear magnetic resonance (NMR) and infrared spectroscopy (IR), and field emission scanning electron microscopy (FESEM)/transmission electron microscopy (TEM), showing their physicochemical properties. The specific capacity of the metalorganic materials to be exfoliated through post-synthesis treatments, using several solvents due to the presence of 1D structure sub-units and a marked hydrophobic nature, was also evidenced. ; The authors are grateful for financial support from the Spanish Government by MAT2017-82288-C2-1-P and Severo Ochoa Excellence Program SEV-2016-0683. J. M. M. acknowledges Predoctoral Fellowships from MINECO for economical support. The authors thank the MULTY2HYCAT EU-Horizon 2020 funded project under grant agreement no.720783. ; Moreno-Rodríguez, JM.; Velty, A.; Díaz Morales, UM. (2019). Expandable Layered Hybrid Materials Based on Individual 1D Metalorganic Nanoribbons. Materials. 12(12):1-13. https://doi.org/10.3390/ma12121953 ; S ; 1 ; 13 ; 12 ; 12 ; Nakagawa, K., Yamaguchi, K., Yamada, K., Sotowa, K.-I., Sugiyama, S., & Adachi, M. (2012). Synthesis and Characterization of Surface-Functionalized Layered Titanate Nanosheets Using Lamellar Self-Assembly as a Template. European Journal of Inorganic Chemistry, 2012(16), 2741-2748. doi:10.1002/ejic.201101136 ; Koene, B. E., Taylor, N. J., & Nazar, L. F. (1999). An Inorganic Tire-Tread Lattice: Hydrothermal Synthesis of the Layered Vanadate [N(CH3)4]5V18O46 with a Supercell Structure. Angewandte Chemie ...

[EN] Novel MOF-type materials with different morphologies based on assembled 1D organic-inorganic subdomains were prepared using specific monodentate benzylcarboxylate spacers with functional substituents in the para-position as structure modulating agents. The combination of electronwithdrawing or electron-donating functions in the organic spacers with suitable solvothermal synthesis conditions allowed modulating the structuration level (2D or 3D), vacancies, physico-chemical properties and Lewis acidity strength of the metal-organic structures. Furthermore, bimetallic (Al/ Fe) MOF-type materials were synthesized by a one-pot direct process without modification of the structural framework. The activity of these hybrid materials as Lewis acid catalysts was evaluated to prepare cyanohydrins as precursors for the synthesis of biologically active compounds, and for aerobic oxidation of thiols to disulfides. The catalytic results showed that the derived MOFs exhibited modulatable Lewis acid capacities which are a function of the morphology, functionality of monodentate substituents present in the networks and a cooperative effect between metallic nodes of different nature. ; The authors are grateful for financial support from the Spanish Government by MAT2014-52085-C2-1-P, MAT2017-82288-C2-1-P and Severo Ochoa Excellence Program SEV-2016-0683. J. M. M. acknowledges Predoctoral Fellowships from MINECO for economical support. The authors thank the MULTY2HYCAT (EU-Horizon 2020 funded project under grant agreement no. 720783). The European Union is also acknowledged by ERC-AdG-2014-671093-SynCatMatch. ; Moreno-Rodríguez, JM.; Velty, A.; Díaz Morales, UM.; Corma Canós, A. (2019). Synthesis of 2D and 3D MOFs with tuneable Lewis acidity from preformed 1D hybrid sub-domains. Chemical Science. 10(7):2053-2066. https://doi.org/10.1039/c8sc04372h ; S ; 2053 ; 2066 ; 10 ; 7 ; Furukawa, H., Cordova, K. E., O'Keeffe, M., & Yaghi, O. M. (2013). The Chemistry and Applications of Metal-Organic Frameworks. Science, 341(6149), ...

[EN] A new family of stable layered organic-inorganic materials has been prepared, in one-step solvothermal process. They are based on an ordered nickel cluster-type nanoribbons separated from each other by specific alkyl (heptyl- or dodecyl-) arylic mono-carboxylate moieties acting as molecular spacers, perpendicular to the 1D inorganic chains. These organic spacers contain hydrocarbon tails with different length which control the separation level between inorganic 1D sub-units, inhibiting the 3D growth of conventional DUT-8-type metal-organic frameworks (MOFs). The lamellar nature of the materials formed was studied and confirmed by different characterization techniques, showing the structural location of individual organic and inorganic building units. They have been successfully used as a long-lasting biodegradable and water-proof materials for controlled release of chemicals, such as pheromones for sustainable treatment of insect plagues. ; The support of the European Union (ERC-AdG-2014-671093—SynCatMatch) and the Spanish Government (MAT2014-52085-C2-1-P and Severo Ochoa program SEV2012-0267) is acknowledged. ; Moreno Rodríguez, JM.; Navarro Fuertes, I.; Díaz Morales, UM.; Primo Millo, J.; Corma Canós, A. (2016). Single-Layered Hybrid Materials Based on 1D Associated Metalorganic Nanoribbons for Controlled Release of Pheromones. Angewandte Chemie International Edition. 55(37):11026-11030. https://doi.org/10.1002/anie.201602215 ; S ; 11026 ; 11030 ; 55 ; 37

[EN] In the presented study, H-Beta zeolite and H-Beta/meso (mesoporous Beta zeolite obtained by a mesotemplate-free method) were modified with Fe-3, Fe2Cr, FeCr2 and Cr-3 triple-metallic aggregates (oligocations) by ion-exchange method (for comparison modification with isolated Fe cations was also done). Successful synthesis of mesoporous Beta zeolite was confirmed by several techniques such as N-2-sorption, PXRD, AAS or NH3-TPD. Modified porosity and acidity of the Beta zeolite, as well as the source of metals used, influenced the form (coordination and aggregation), content and reducibility of Fe- and Cr-species in the samples (UV-vis-DRS, AAS, H-2-TPR). The obtained samples were tested as catalysts in the process of selective catalytic oxidation of ammonia to dinitrogen (NH3-SCO). The highest activity and selectivity for nitrogen was obtained for the bimetallic Fe-Cr samples prepared by deposition of suitable oligocations. ; This work was carried out in the frame of project No. 0670/IP3/2016/74 from the Polish Ministry of Science and Higher Education in the years 2016-2019 and in the frame of project No. 2012/05/B/ST5/00269 from the National Science Centre (Poland). U. D. acknowledges to the Spanish Government for funding (MAT2017-82288-C2-1-P). ; Rutkowska, M.; Duda, M.; Macina, D.; Górecka, S.; Debek, R.; Moreno-Rodríguez, JM.; Díaz Morales, UM. (2019). Mesoporous Beta zeolite functionalisation with FexCry oligocations; catalytic activity in the NH3-SCO process. Microporous and Mesoporous Materials. 278:1-13. https://doi.org/10.1016/j.micromeso.2018.11.003 ; S ; 1 ; 13 ; 278 ; Chmielarz, L., & Jabłońska, M. (2015). Advances in selective catalytic oxidation of ammonia to dinitrogen: a review. RSC Advances, 5(54), 43408-43431. doi:10.1039/c5ra03218k ; Jabłońska, M., & Palkovits, R. (2016). Copper based catalysts for the selective ammonia oxidation into nitrogen and water vapour—Recent trends and open challenges. Applied Catalysis B: Environmental, 181, 332-351. doi:10.1016/j.apcatb.2015.07.017 ; QI, ...