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[EN] The preparation of continuous layers of highly hydrophobic pure silica ITQ-29 zeolite, potentially applicable as hydrophobic membranes for separation of molecules based on their polarity, has been investigated. Continuous layers of intergrown ITQ-29 zeolite crystals were successfully grown on porous alumina supports by optimization of the synthesis conditions, such as the appropriate selection of the seeds, the procedure for the gel preparation, and the calcination conditions. This resulted in the formation of all silica ITQ-29 zeolite layers without the presence of germanium required in previously reported ITQ-29 membranes, with the subsequent improvement in quality and stability, as verified by the absence of cracks after calcination. We have proved that the incorporation of aluminum from the support into the zeolite layer does not occur, neither during the secondary growth nor through migration of aluminum species during calcination. ; This research was funded by the European Research Council, grant ERC-AdG-2014-671093 (SynCatMatch) and the Spanish Government, through "Severo Ochoa" grant SEV-2016-0683 and RTI2018-101784-B-I00. ; Palomino Roca, M.; Ono, H.; Valencia Valencia, S.; Corma Canós, A. (2020). Preparation of Continuous Highly Hydrophobic Pure Silica ITQ-29 Zeolite Layers on Alumina Supports. Molecules. 25(18):1-13. https://doi.org/10.3390/molecules25184150 ; S ; 1 ; 13 ; 25 ; 18 ; Mascal, M. (2012). Chemicals from biobutanol: technologies and markets. Biofuels, Bioproducts and Biorefining, 6(4), 483-493. doi:10.1002/bbb.1328 ; Ndaba, B., Chiyanzu, I., & Marx, S. (2015). n-Butanol derived from biochemical and chemical routes: A review. Biotechnology Reports, 8, 1-9. doi:10.1016/j.btre.2015.08.001 ; Huang, H.-J., Ramaswamy, S., & Liu, Y. (2014). Separation and purification of biobutanol during bioconversion of biomass. Separation and Purification Technology, 132, 513-540. doi:10.1016/j.seppur.2014.06.013 ; Barton, W. E., & Daugulis, A. (1992). Evaluation of solvents for extractive ...

1 13 25 18 ; S ; [EN] The preparation of continuous layers of highly hydrophobic pure silica ITQ-29 zeolite, potentially applicable as hydrophobic membranes for separation of molecules based on their polarity, has been investigated. Continuous layers of intergrown ITQ-29 zeolite crystals were successfully grown on porous alumina supports by optimization of the synthesis conditions, such as the appropriate selection of the seeds, the procedure for the gel preparation, and the calcination conditions. This resulted in the formation of all silica ITQ-29 zeolite layers without the presence of germanium required in previously reported ITQ-29 membranes, with the subsequent improvement in quality and stability, as verified by the absence of cracks after calcination. We have proved that the incorporation of aluminum from the support into the zeolite layer does not occur, neither during the secondary growth nor through migration of aluminum species during calcination. This research was funded by the European Research Council, grant ERC-AdG-2014-671093 (SynCatMatch) and the Spanish Government, through "Severo Ochoa" grant SEV-2016-0683 and RTI2018-101784-B-I00. Palomino Roca, M.; Ono, H.; Valencia Valencia, S.; Corma Canós, A. (2020). Preparation of Continuous Highly Hydrophobic Pure Silica ITQ-29 Zeolite Layers on Alumina Supports. Molecules. 25(18):1-13. https://doi.org/10.3390/molecules25184150 Mascal, M. (2012). Chemicals from biobutanol: technologies and markets. Biofuels, Bioproducts and Biorefining, 6(4), 483-493. doi:10.1002/bbb.1328 Ndaba, B., Chiyanzu, I., & Marx, S. (2015). n-Butanol derived from biochemical and chemical routes: A review. Biotechnology Reports, 8, 1-9. doi:10.1016/j.btre.2015.08.001 Huang, H.-J., Ramaswamy, S., & Liu, Y. (2014). Separation and purification of biobutanol during bioconversion of biomass. Separation and Purification Technology, 132, 513-540. doi:10.1016/j.seppur.2014.06.013 Barton, W. E., & Daugulis, A. (1992). Evaluation of solvents for extractive butanol fermentation ...

[EN] Different bi-functional materials (Pd(Au)@TS-1) based on metallic nanoparticles supported onto active nanocrystalline titanium silicalite (TS-1) zeolites were synthesized, characterized and used as recyclable heterogeneous catalysts for direct propylene oxide production from hydrogen, oxygen and propylene through one-pot two-step consecutive process. These catalysts allowed carrying out the combined reaction where metallic nanoparticles catalyzed the formation of in situ H2O2 that was the necessary intermediate for propylene epoxidation catalyzed by active TS-1 nanocrystalline support. Several variables were considered such as use of supercritical CO2 conditions, modifiable content of metallic species, and presence of additional co-solvents, surface acidity inhibitors and H2O2 stabilizers. Reusability and stability of the bi-functional catalyst was showed through consecutive catalytic cycles. ; The research leading to these results has received funding from European Community's Seventh Framework Programme, through the Collaborative Project INCAS, Contract Nr. NMP2-LA-2010- 245988. Authors thank additional funds from Spanish Government (MAT2014-52085-C2-1-P and Severo Ochoa Excellence Program SEV-2012-0267). ; Prieto Arnal, A.; Palomino Roca, M.; Díaz Morales, UM.; Corma Canós, A. (2016). One-pot two-step process for direct propylene oxide production catalyzed by bi-functional Pd(Au)@TS-1 materials. Applied Catalysis A: General. 523:73-84. https://doi.org/10.1016/j.apcata.2016.05.019 ; S ; 73 ; 84 ; 523

[EN] Several bi-functional materials based on palladium nanoparticles supported onto nanocrystalline tita-nium silicalite zeolite (Pd@TS-1) were prepared and used as active and reusable catalysts to direct POproduction from hydrogen, oxygen and propylene through one-pot two-step combined process. Thistype of catalysts was able to carry out the consecutive process where palladium nanoparticles catalyzed the formation of H2O2that was used as intermediate reagent for propylene epoxidation catalyzed byTS-1 nanocrystals, used as supporting active matrix. Influence of supercritical CO2conditions in batch reactions was evaluated together with the associated effect due to the presence of platinum promoters (Pd(Pt)@TS-1). Other reaction parameters were also considered, such as palladium loading, use of acid-ity inhibitors and modification of H2/O2/C3ratio. Reusability studies showed the high stability of thec atalysts in consecutive catalytic cycles, their regeneration being possible. ; The research leading to these results has received funding from European Community's Seventh Framework Program, through the Collaborative Project INCAS, Contract Nr. NMP2-LA-2010-245988. AP and UD thank additional funds from Spanish Government (MAT2011-29020-C02-01, Consolider-Ingenio MULTICAT C5D2009-00050 ; Prieto Arnal, A.; Palomino Roca, M.; Díaz Morales, UM.; Corma Canós, A. (2014). Propylene epoxidation with in situ generated H2O2 in supercritical conditions. Catalysis Today. 227:87-95. https://doi.org/10.1016/j.cattod.2013.10.004 ; S ; 87 ; 95 ; 227

Mixed-matrix membranes (MMM) consisting of poly(1-trimethylsilyl-1-propyne) (PTMSP) as continuous matrix and small-pore LTA-framework zeolites with Si/Al ratios from 1 (commercial zeolite A) to ¥ (ITQ-29) as dispersed phase were prepared by solution casting. The thermal stability of the MMM is as high as that of glassy PTMSP polymer, whose high permeability is maintained even at increasing temperature. The effect of the Si/Al ratio in the zeolite fillers on the membrane performance is observed by the increasing CO2/N2 permselectivity of low-Si/Al ratio zeolite A-based membranes, in comparison with pure silica ITQ-29. The performance of the LTA-type zeolite-PTMSP MMM was adjusted to the modified Maxwell model by estimating the chain immobilization factor and the interphase thickness as a function of temperature, Si/Al ratio, and zeolite loading ; Financial support from the Spanish Ministry of Economy and Competitiveness (MINECO) under project CTQ2012-31229 at the Universidad de Cantabria is gratefully acknowledged. A.F.B. and C.C.C. also thank the MINECO for the Early Stage Researcher (BES2013-064266) and "Ramon y Cajal" (RYC2011-0855) grants, respectively. M.P. and S.V. also gratefully acknowledge the financial support from the Spanish Government (MAT2012-38567-C02-01, Consolider Ingenio 2010-Multicat CSD-2009-00050 and Severo Ochoa SEV-2012-0267). ; Fernández-Barquín, A.; Casado-Coterillo, C.; Palomino Roca, M.; Valencia Valencia, S.; Irabien, Á. (2015). LTA/Poly(1-trimethylsilyl-1-propyne) Mixed-Matrix Membranes for High-Temperature CO2/N2 Separation. Chemical Engineering and Technology. 38(4):658-666. https://doi.org/10.1002/ceat.201400641 ; S ; 658 ; 666 ; 38 ; 4

Mixed-matrix membranes (MMM) consisting of poly(1-trimethylsilyl-1-propyne) (PTMSP) as continuous matrix and small-pore LTA-framework zeolites with Si/Al ratios from 1 (commercial zeolite A) to ¥ (ITQ-29) as dispersed phase were prepared by solution casting. The thermal stability of the MMM is as high as that of glassy PTMSP polymer, whose high permeability is maintained even at increasing temperature. The effect of the Si/Al ratio in the zeolite fillers on the membrane performance is observed by the increasing CO2/N2 permselectivity of low-Si/Al ratio zeolite A-based membranes, in comparison with pure silica ITQ-29. The performance of the LTA-type zeolite-PTMSP MMM was adjusted to the modified Maxwell model by estimating the chain immobilization factor and the interphase thickness as a function of temperature, Si/Al ratio, and zeolite loading. ; Financial support from the Spanish Ministry of Economy and Competitiveness (MINECO) under project CTQ2012-31229 at the Universidad de Cantabria is gratefully acknowledged. A.F.B. and C.C.C. also thank the MINECO for the Early Stage Researcher (BES2013-064266) and "Ramón y Cajal" (RYC2011-0855) grants, respectively. M.P. and S.V. also gratefully acknowledge the financial support from the Spanish Government (MAT2012-38567-C02-01, Consolider Ingenio 2010-Multicat CSD-2009-00050 and Severo Ochoa SEV-2012-0267).

[EN] Here we present two FeII coordination polymers that possess discrete compartments suitable for CO2 physisorption despite the lack of permanent channels. The two crystalline materials, of general formula [Fe(btzbp)3](X)2 (X = ClO4 or BF4), present voids of ca. 250 Å3, which each can accommodate up to two CO2 molecules. The abrupt spin transition can be modified upon CO2 sorption, and different magnetic behaviour is observed depending on the number of molecules sorbed. ; Financial support from the Spanish MINECO (CTQ2014-59209-P, MAT2014-56143-R and MAT2012-38567-C02-01), the Generalitat Valenciana (Prometeo and ISIC-Nano programs) and the VLC/Campus Program is gratefully acknowledged. We thank the Spanish government for the provision of a Severo Ochoa project (SEV-2012-0267) and a Maria de Maeztu project (MDM-2015-0538). G.M.E. acknowledges the Blaise Pascal International Chair for financial support. M.G.-M. thanks MICINN for a predoctoral FPU grant and the EU for a Marie Sklodowska-Curie postdoctoral fellowship (H2020-MSCA-IF-EF-658224). N.C.G. thanks the Generalitat Valenciana for a Val-i+d predoctoral fellowship. J. M. Martinez-Agudo and G. Agusti from the University of Valencia are gratefully acknowledged for magnetic measurements. ; Calvo Galve, N.; Giménez-Marqués, M.; Palomino Roca, M.; Valencia Valencia, S.; Rey Garcia, F.; Mínguez Espallargas, G.; Coronado, E. (2016). Isostructural compartmentalized spin-crossover coordination polymers for gas confinement. Inorganic Chemistry Frontiers. 3(6):808-813. https://doi.org/10.1039/C5QI00277J ; S ; 808 ; 813 ; 3 ; 6 ; Hoskins, B. F., & Robson, R. (1989). Infinite polymeric frameworks consisting of three dimensionally linked rod-like segments. Journal of the American Chemical Society, 111(15), 5962-5964. doi:10.1021/ja00197a079 ; Hoskins, B. F., & Robson, R. (1990). Design and construction of a new class of scaffolding-like materials comprising infinite polymeric frameworks of 3D-linked molecular rods. A reappraisal of the zinc cyanide and cadmium ...

[EN] Herein we report the synthesis of an elusive metal-organic framework, the iron(II) analogue of ZIF-8 with the formula Fe(2-methylimidazolate)(2), here denoted as MUV-3. The preparation of this highly interesting porous material, inaccessible by common synthetic procedures, occurs in a solvent-free reaction upon addition of an easily detachable template molecule, yielding single crystals of MUV-3. This methodology can be extended to other metals and imidazolate derivatives, allowing the preparation of ZIF-8, ZIF-67, and the unprecedented iron(II) ZIFs Fe(2-ethylimidazolate)(2) and Fe(2-methylbenzimidazolate)(2). The different performance of MUV-3 toward NO sorption, in comparison to ZIF-8, results from the chemisorption of NO molecules, which also causes a gate-opening behavior. Finally, the controlled pyrolysis of MUV-3 results in a N-doped graphitic nanocomposite that exhibits extraordinary performance for the oxygen evolution reaction (OER), with low overpotential at different current densities (316 mV at 10 mA cm(-2)), low Tafel slope (37 mV per decade), high maximum current density (710 mA cm(-2) at 2.0 V vs RHE), and great durability (15 h). ; The work has been supported by the European Union (ERC-2016-CoG 724681-S-CAGE and ERC-2018-StG 804110-2D-PnictoChem) and the Spanish MINECO (Structures of Excellence Maria de Maeztu MDM-2015-0538 and Severo Ochoa SEV-2016-0683; projects CTQ2014-59209-P, CTQ2017-89528-P, and MAT2015-71842-P). G.M.E. and M.G.-M. thank the MICINN for "Ramon y Cajal" and "Juan de la Cierva - Incorporacion" fellowships, respectively. J.L.-C. acknowledges the Universitat de Valencia for an "Atraccio de Talent" grant. G.A. acknowledges support by the Generalitat Valenciana (CIDEGENT/2018/001) and the Deutsche Forschungsgemeinschaft (DFG; FLAG-ERA AB694/2-1). Dr. F. Hauke and Prof. A. Hirsch are acknowledged for their kind support with the Raman equipment. ; Lopez-Cabrelles, J.; Romero, J.; Abellán Sáez, G.; Gimenez-Marques, M.; Palomino Roca, M.; Valencia Valencia, S.; Rey Garcia, F. ...

[EN] The synthesis of a new microporous metal-organic framework (MOF) based on two secondary building units, with dinuclear cobalt centers, has been developed. The employment of a well-defined cobalt cluster results in an unusual topology of the Co-2-MOF, where one of the cobalt centers has three open coordination positions, which has no precedent in MOF materials based on cobalt. Adsorption isotherms have revealed that Co-2-MOF is in the range of best CO2 adsorbents among the carbon materials, with very high CO2/CH4 selectivity. On the other hand, dispersion of Co-2-MOF in an alcoholic solution of Nafion gives rise to a composite (Co-2-MOF@Nafion) with great resistance to hydrolysis in aqueous media and good adherence to graphite electrodes. In fact, it exhibits high electrocatalytic activity and robustness for the oxygen evolution reaction (OER), with a turnover frequency number value superior to those reported for similar electrocatalysts. Overall, this work has provided the basis for the rational design of new cobalt OER catalysts and related materials employing well-defined metal clusters as directing agents of the MOF structure. ; The authors thank Prof. Avelino Corma for discussion and support, and J. Mazario for XPS analysis and discussion. Program Severo Ochoa SEV-2016-0683 is gratefully acknowledged. S.G.-T. thanks MINECO for a FPU Ph.D. fellowship FPU16/02117. P.O.-B. thanks MEC for his Ramon y Cajal contract RYC-2014-16620. The authors thank the financial support by the Spanish Government (RTI2018-096399-A-I00, RTI2018-101784-B-I00, and CTQ2014-52641-P). In addition, P.O.-B. thanks UPV for his grant PAID-06-18/SP20180172. The Electron Microscopy Service of the UPV is acknowledged for their help in sample characterization. ; Gutiérrez-Tarriño, S.; Olloqui Sariego, JL.; Calvente, JJ.; Palomino Roca, M.; Mínguez Espallargas, G.; Jorda Moret, JL.; Rey Garcia, F. (2019). Cobalt Metal Organic Framework Based on Two Dinuclear Secondary Building Units for Electrocatalytic Oxygen Evolution. ACS Applied ...

10036 10043 22 29 ; S ; Incorporation of germanium in zeolites is well known to confer static flexibility to their framework, by stabilizing the formation of small rings. In this work, we show that the flexibility associated to Ge atoms in zeolites goes beyond this static effect, manifesting also a clear dynamic nature, in the sense that it leads to enhanced molecular diffusion. Our study combines experimental and theoretical methods providing evidence for this effect, which has not been described previously, as well as a rationalization for it, based on atomistic grounds. We have used both pure-silica and silico-germanate ITQ-29 (LTA topology) zeolites as a case study. Based on our simulations, we identify the flexibility associated to the pore breathing-like behavior induced by the Ge atoms, as the key factor leading to the enhanced diffusion observed experimentally in Ge-containing zeolites. We thank the contribution from the European Research Council through an ERC Starting Grant (ERC2011-StG-279520-RASPA), the MINECO (CTQ2013-48396-P), the Andalucia Region (FQM-1851) and the Royal Society (International Exchange Scheme grant REA004). We thank Centro Informatico Cientifico de Andalucia (CICA) for providing computing resources. M.P., F.R. and S.V. thank the financial support by the Spanish Government (MAT2015-71842-P, Consolider Ingenio 2010-Multicat CSD-2009-00050 and Severo Ochoa SEV-2012-0267). Gutierrez-Sevillano, JJ.; Calero, S.; Hamad, S.; Grau-Crespo, R.; Rey Garcia, F.; Valencia Valencia, S.; Palomino Roca, M. (2016). Critical Role of Dynamic Flexibility in Ge-Containing Zeolites: Impact on Diffusion. Chemistry - A European Journal. 22(29):10036-10043. https://doi.org/10.1002/chem.201600983

Incorporation of germanium in zeolites is well known to confer static flexibility to their framework, by stabilizing the formation of small rings. In this work, we show that the flexibility associated to Ge atoms in zeolites goes beyond this static effect, manifesting also a clear dynamic nature, in the sense that it leads to enhanced molecular diffusion. Our study combines experimental and theoretical methods providing evidence for this effect, which has not been described previously, as well as a rationalization for it, based on atomistic grounds. We have used both pure-silica and silico-germanate ITQ-29 (LTA topology) zeolites as a case study. Based on our simulations, we identify the flexibility associated to the pore breathing-like behavior induced by the Ge atoms, as the key factor leading to the enhanced diffusion observed experimentally in Ge-containing zeolites. ; We thank the contribution from the European Research Council through an ERC Starting Grant (ERC2011-StG-279520-RASPA), the MINECO (CTQ2013-48396-P), the Andalucia Region (FQM-1851) and the Royal Society (International Exchange Scheme grant REA004). We thank Centro Informatico Cientifico de Andalucia (CICA) for providing computing resources. M.P., F.R. and S.V. thank the financial support by the Spanish Government (MAT2015-71842-P, Consolider Ingenio 2010-Multicat CSD-2009-00050 and Severo Ochoa SEV-2012-0267). ; Gutierrez-Sevillano, JJ.; Calero, S.; Hamad, S.; Grau-Crespo, R.; Rey Garcia, F.; Valencia Valencia, S.; Palomino Roca, M. (2016). Critical Role of Dynamic Flexibility in Ge-Containing Zeolites: Impact on Diffusion. Chemistry - A European Journal. 22(29):10036-10043. https://doi.org/10.1002/chem.201600983 ; S ; 10036 ; 10043 ; 22 ; 29

[EN] Herein we report the synthesis of a tetrathiafulvalene (TTF)-based MOF, namely MUV-2, which shows a non-interpenetrated hierarchical crystal structure with mesoporous one-dimensional channels of ca. 3 nm and orthogonal microporous channels of ca. 1 nm. This highly stable MOF (aqueous solution with pH values ranging from 2 to 11 and different organic solvents), which possesses the well-known [Fe3(¿3-O)(COO)6] secondary building unit, has proven to be an efficient catalyst for the aerobic oxidation of dibenzothiophenes. ; The work has been supported by the European Union (ERC-2016-CoG 724681-S-CAGE) and the Spanish MINECO (CTQ 2014-59209-P, CTQ2017-89528-P and MAT2015-71842-P). We also thank the Spanish government for the provision of a Severo Ochoa project (SEV-2016-0683) and a Maria de Maeztu project (MDM-2015-0538). G.M.E. and M.S. thank MINECO for a Ramon y Cajal and a Juan de la Cierva-Formacion fellowships, respectively. We thank J. M. Martinez-Agudo, G. Agusti and J. Romero from the University of Valencia for their magnetic and cyclic voltammetry measurements. We thank the Diamond Light Source (UK) for the synchrotron beamtime. C2TN/IST authors acknowledge the Portuguese Foundation for Science and Technology (FCT), contract UID/Multi/04349/2013. ; Souto, M.; Santiago-Portillo, A.; Palomino Roca, M.; Vitorica-Yrezabal, IJ.; Vieira, BJC.; Waerenborgh, JC.; Valencia Valencia, S. (2018). A highly stable and hierarchical tetrathiafulvalene-based metal organic framework with improved performance as a solid catalyst. Chemical Science. 9(9):2413-2418. https://doi.org/10.1039/c7sc04829g ; S ; 2413 ; 2418 ; 9 ; 9 ; Furukawa, H., Cordova, K. E., O'Keeffe, M., & Yaghi, O. M. (2013). The Chemistry and Applications of Metal-Organic Frameworks. Science, 341(6149), 1230444-1230444. doi:10.1126/science.1230444 ; Zhou, H.-C. «Joe», & Kitagawa, S. (2014). Metal–Organic Frameworks (MOFs). Chem. Soc. Rev., 43(16), 5415-5418. doi:10.1039/c4cs90059f ; Maurin, G., Serre, C., Cooper, A., & Férey, G. (2017). The new ...

[EN] Discrimination between different gases is an essential aspect for industrial and environmental applications involving sensing and separation. Several classes of porous materials have been used in this context, including zeolites and more recently MOFs. However, to reach high selectivities for the separation of gas mixtures is a challenging task that often requires the understanding of the specific interactions established between the porous framework and the gases. Here we propose an approach to obtain an enhanced selectivity based on the use of compartmentalized coordination polymers, named CCP-1 and CCP-2, which are crystalline materials comprising isolated discrete cavities. These compartmentalized materials are excellent candidates for the selective separation of CO2 from methane and nitrogen. A complete understanding of the sorption process is accomplished with the use of complementary experimental techniques including X-ray diffraction, adsorption studies, inelastic- and quasi-elastic neutron scattering, magnetic measurements and molecular dynamics calculations. ; Financial support from the Spanish MINECO (CTQ2014-59209-P, MAT2014-56143-R and MAT2015-71842-P), the Generalitat Valenciana (Prometeo and ISIC-Nano programs), the EU (ERC-2016-CoG 724681-S-CAGE) and the VLC/Campus Program is gratefully acknowledged. We thank the Spanish government for the provision of a Severo Ochoa project (SEV-2012-0267) and a Maria de Maeztu project (MDM-2015-0538). M. G.-M. thanks MICINN for a predoctoral FPU grant and the EU for a Marie Sklodowska-Curie postdoctoral fellowship (H2020-MSCA-IF-EF-658224). N. C. G. thanks the Generalitat Valenciana for a VALi+d predoctoral fellowship. J. A. R. -V. acknowledges CSIC for a JAE-doc contract. G. S. thanks SGAI-CSIC for computing time. G. M. E. acknowledges the Blaise Pascal International Chair for financial support and the Ramon y Cajal Programme. J. M. Martinez-Agudo and G. Agusti from the University of Valencia are gratefully acknowledged for magnetic measurements. We are ...