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628 638 3 8 ; S ; [EN] Modulating the structures of subnanometric metal clusters at the atomic level is a great synthetic and characterization challenge in catalysis. Here, we show how the catalytic properties of subnanometric platinum clusters (0.5-0.6 nm) confined in the sinusoidal 10R channels of purely siliceous MFI zeolite are modulated upon introduction of partially reduced tin species that interact with the noble metal at the metal/support interface. The platinum-tin clusters are stable in H(2)over an extended period of time (>6 h), even at high temperatures (for example, 600 degrees C), which is determined by only a few additional tin atoms added to the platinum clusters. The structural features of platinum-tin clusters, which are not immediately visible by conventional characterization techniques but can be established after combination of in situ extended X-ray absorption fine structure, high-angle annular dark-field scanning transmission electron microscopy and CO infrared data, are key to providing a one-order of magnitude lower deactivation rate in the propane dehydrogenation reaction while maintaining high intrinsic (initial) catalytic activity This work was supported by the European Union through the European Research Council (grant ERC-AdG-2014-671093, SynCatMatch) and the Spanish government through the "Severo Ochoa Program" (SEV-2016-0683). L.L. thanks the ITQ for providing a contract. The authors also thank the Microscopy Service of the UPV for the TEM and STEM measurements. The XAS measurements were carried out in the CLAESS beamline of the ALBA synchrotron. We thank Giovanni Agostini for his kind support in the analysis of XAS data. HR-HAADF-STEM measurements were performed at DME-UCA at Cadiz University with financial support from FEDER/MINECO (MAT2017-87579-R and MAT2016-81118-P). C.W.L. thanks CAPES (Science without Frontiers -Process no. 13191/13-6) for a predoctoral fellowship. The financial support from ExxonMobil for this project is also greatly acknowledged. Liu, L.; Lopez-Haro, ...

[EN] Ruthenium nanoparticles with a core-shell structure formed by a core of metallic ruthenium and a shell of ruthenium carbide have been synthesized by a mild and easy hydrothermal treatment. The dual structure and composition of the nanoparticles have been determined by synchrotron X-ray photoelectron spectroscopy (XPS), near-edge X-ray absorption fine structure (NEXAFS) analysis, and transmission electron microscopy (TEM) imaging. According to depth profile synchrotron XPS and X-ray diffraction (XRD) analysis, metallic ruthenium species predominate in the inner layers of the material, ruthenium carbide species being located on the upper surface layers. The ruthenium carbon catalysts presented herein are able to activate both CO2 and H-2, exhibiting exceptional high activity for CO2 hydrogenation at low temperatures (160-200 degrees C) with 100% selectivity to methane, surpassing by far the most active Ru catalysts reported up to now. On the basis of catalytic studies and isotopic (CO)-C-13/(CO2)-C-12/H-2 experiments, the active sites responsible for this unprecedented activity can be associated with surface ruthenium carbide (RuC) species, which enable CO2 activation and transformation to methane via a direct CO2 hydrogenation mechanism. Both the high activity and the absence of CO in the gas effluent confer relevance to these catalysts for the Sabatier reaction, a chemical process with renewed interest for storing surplus renewable energy in the form of methane. ; The research leading to these results has received funding from the Spanish Ministry of Science, Innovation and Universities through "Severo Ochoa" Excellence Programme (SEV-2016-0683) and the PGC2018-097277-B-100 (MCIU/AEI/FEDER, UE) project. The authors also thank the Microscopy Service of UPV for kind help with measurements. A G.O. thanks "Severo Ochoa" Programme (SEV-2016-0683) for a predoctoral fellowship. C.-H.C. acknowledges financial support from MOST project 107-2112-M-032-005. J.C. thanks the Spanish Government (MINECO) for a "Severo ...

[EN] The synthesis of the ZSM-5 and beta zeolites in their nanosized form has been achieved by using simple alkyl-substituted mono-cationic cyclic ammonium cations as OSDA molecules. The particular combination of a cyclic fragment and a short linear alkyl-chain group (preferentially C4) within the monocationic OSDA molecules allows directing the crystallization of nanosized zeolites with excellent solid yields (above 90%). Interestingly, the formation of the nanosized ZSM-5 and beta zeolites mostly depends on the size and nature of the cyclic fragment of the OSDA molecule, resulting in all cases in nanocrystalline solids with homogeneous distributions of particle sizes (similar to 10-25 nm) and controlled Si/Al molar ratios (similar to 15-30). The achieved nanosized ZSM-5 and beta zeolites have been extensively characterized by different techniques to study their physico-chemical properties, such as chemical composition, pore accessibility or Bronsted acidity, among others. Moreover, the catalytic properties of the nanosized ZSM-5 and beta zeolites have been evaluated for different chemical reactions, including methanol-to-olefins (MTO) in the case of ZSM-5, and alkylation of benzene with propylene to obtain cumene and oligomerization of light olefins to liquid fuels in the case of beta, observing in all cases improved catalytic activity and product selectivity towards target products when compared to related catalysts. ; This work has been supported by the Spanish Government-MINECO through "Severo Ochoa" (SEV 2012-0267), MAT2015-71261-R and CTQ2015-70126-R, by the European Union through ERC-AdG-2014-671093 (SynCatMatch) and by the Fundacion Ramon Areces through a research contract of the "Life and Materials Science" program. E. M. G. and M. R. D-R. acknowledge "La Caixa - Severo Ochoa" International PhD Fellowships (call 2015). M. E. M-A. thanks MINECO for economical support through pre-doctoral fellowship (BES-2013-066800). The Electron Microscopy Service of the UPV is acknowledged for their help in sample ...

[EN] In this work a new ultrafast data collection strategy for electron diffraction tomography is presented that allows reducing data acquisition tithe by one order of Magnitude.,,This Methodology minimizes the radiation damage of, beam-sensitive materials, such as microporous materials. This method, combined with the precession of the electron beam, provides high quality data enabling the determination of very complex structures. Most importantly,, the implementation of this new, electron diffraction methodology is, easily affordable in any modem electron Microscope. As a proof of concept, we have solved a new highly complex zeolitic structure named ITQ-58, with a very low symmetry (triclinic) and a large unit cell volume (1874.61(3)), containing 16 silicon and 32 oxygen atoms in its asymmetric unit, which would be very difficult to solve with the state of the art techniques. ; The authors gratefully acknowledge financial support of European Research Council (ERC-2014-AdG ref 671093 "MATching zeolite SYNthesis with CATalytic activity"), Spanish Government (MAT2015-71842-P (MINECO/FEDER), MAT2012-38567-C02-01 and Severo Ochoa SEV-2012-0267), and Generalitat Valenciana (Project Prometeo). E.M. was also supported by the Italian project FIR2013 Exploring the Nanoworld. Authors thank beamline MSPD at Spanish Synchrotron ALBA for beam time allocation. We acknowledge JEOL Japan, JEOL Europe, and specially Junichi Morimoto from JEOL Europe for the assistance during the specific alignments of the microscope. Finally, authors specially thank the Electron Microscopy Service of the Universitat Politecnica de Valencia and, in particular, Manuel J. Planes and Jose L. Moya for their invaluable support for setting up the EDT data acquisition. Original data (collected EDT frames and integrated intensities) can be requested directly from corresponding authors. ; Simancas-Coloma, J.; Simancas Coloma, R.; Bereciartua-Pérez, PJ.; Jorda Moret, JL.; Rey Garcia, F.; Corma Canós, A.; Nicolopoulos ., S. (2016). Ultrafast Electron ...

2122 2125 54 17 ; S Ch. Baerlocher , A.Hepp and W. M.Meier , DLS-76. Distance least squares refinement program , ETH Zurich Institut fur Kristallographie , Zurich, Switzerland , 1977 ; Sun, J., Bonneau, C., Cantín, Á., Corma, A., Díaz-Cabañas, M. J., Moliner, M., … Zou, X. (2009). The ITQ-37 mesoporous chiral zeolite. Nature, 458(7242), 1154-1157. doi:10.1038/nature07957 ; [EN] Here, we present the synthesis and structure determination of the new zeolite ITQ-62. Its structure was determined via ultra-fast electron diffraction tomography and refined using powder XRD data of the calcined material. This new zeolite contains a tridirectional channel system of highly distorted 8-rings, as well as a monodirectional 12-ring channel system. The authors gratefully acknowledge financial support from the Spanish Government (MAT2015-71842-P and MAT2015-71261-R MINECO/FEDER and Severo Ochoa SEV-2016-0683). The authors thank ALBA Light Source for beam allocation at the beamline MSPD, and specially thank the Electron Microscopy Service of the Universitat Politecnica de Valencia. Finally, the authors thank Dr Alejandro Vidal and Dr Teresa Blasco for helping in the NMR data discussion. Bieseki, L.; Simancas Coloma, R.; Jorda Moret, JL.; Bereciartua-Pérez, PJ.; Cantin Sanz, A.; Simancas-Coloma, J.; Pergher, SB. (2018). Synthesis and structure determination via ultra-fast electron diffraction of the new microporous zeolitic germanosilicate ITQ-62. Chemical Communications. 54(17):2122-2125. https://doi.org/10.1039/c7cc09240g Barrer, R. M., & Denny, P. J. (1961). 201. Hydrothermal chemistry of the silicates. Part IX. Nitrogenous aluminosilicates. Journal of the Chemical Society (Resumed), 971. doi:10.1039/jr9610000971 Kerr, G. T. (1966). Chemistry of Crystalline Aluminosilicates. II. The Synthesis and Properties of Zeolite ZK-4. Inorganic Chemistry, 5(9), 1537-1539. doi:10.1021/ic50043a015 Burton, A. W., & Zones, S. I. (2007). Organic Molecules in Zeolite Synthesis: Their Preparation and Structure-Directing Effects. ...

[EN] Here, we present the synthesis and structure determination of the new zeolite ITQ-62. Its structure was determined via ultra-fast electron diffraction tomography and refined using powder XRD data of the calcined material. This new zeolite contains a tridirectional channel system of highly distorted 8-rings, as well as a monodirectional 12-ring channel system. ; The authors gratefully acknowledge financial support from the Spanish Government (MAT2015-71842-P and MAT2015-71261-R MINECO/FEDER and Severo Ochoa SEV-2016-0683). The authors thank ALBA Light Source for beam allocation at the beamline MSPD, and specially thank the Electron Microscopy Service of the Universitat Politecnica de Valencia. Finally, the authors thank Dr Alejandro Vidal and Dr Teresa Blasco for helping in the NMR data discussion. ; Bieseki, L.; Simancas Coloma, R.; Jorda Moret, JL.; Bereciartua-Pérez, PJ.; Cantin Sanz, A.; Simancas-Coloma, J.; Pergher, SB. (2018). Synthesis and structure determination via ultra-fast electron diffraction of the new microporous zeolitic germanosilicate ITQ-62. Chemical Communications. 54(17):2122-2125. https://doi.org/10.1039/c7cc09240g ; S ; 2122 ; 2125 ; 54 ; 17 ; Barrer, R. M., & Denny, P. J. (1961). 201. Hydrothermal chemistry of the silicates. Part IX. Nitrogenous aluminosilicates. Journal of the Chemical Society (Resumed), 971. doi:10.1039/jr9610000971 ; Kerr, G. T. (1966). Chemistry of Crystalline Aluminosilicates. II. The Synthesis and Properties of Zeolite ZK-4. Inorganic Chemistry, 5(9), 1537-1539. doi:10.1021/ic50043a015 ; Burton, A. W., & Zones, S. I. (2007). Organic Molecules in Zeolite Synthesis: Their Preparation and Structure-Directing Effects. Introduction to Zeolite Science and Practice, 137-179. doi:10.1016/s0167-2991(07)80793-2 ; Zones, S. I., Nakagawa, Y., Lee, G. S., Chen, C. Y., & Yuen, L. T. (1998). Searching for new high silica zeolites through a synergy of organic templates and novel inorganic conditions. Microporous and Mesoporous Materials, 21(4-6), 199-211. ...

[EN] Aluminosilicate boggsite (Si/Al-BOG) has been hydrothermally synthesized without adding org. structure-directing agents (OSDAs) in the synthesis gel using the borosilicogermanium ITQ-47 (Si/B-ITQ-47) zeolite as seeds. The introduction of the costly and environmentally less benign phosphazene org. structure-directing agent is not required to grow the zeolite. Physicochem. characterization expts. show that Si/Al-BOG has good crystallinity, high surface area, tetrahedral Al3+ species, and acid sites. In order to test the catalytic performance of the zeolite, the synthesis of L,L-lactide from L-lactic acid was performed. Si/Al-BOG exhibits 88.2% conversion of L-lactic acid and 83.8% L,L-lactide selectivity, which are better than those of other zeolites studied up to now. ; This work was supported by the National Natural Science Foundation of China 21971259 and 91645112, The Natural Science Foundation of Hubei Province of China (2014CFA043), and the Key Research Program of Frontier Sciences, CAS (No. QYZDB-SSW-SLH026). The European Union is also acknowledged by ERC-AdG-2014-671093 SynCatMatch, and the Spanish Government through "Severo Ochoa" (SEV-2016-0683, MINECO). Q. H. acknowledges the International Program Fund for doctoral students, Sun Yat-sen University, for scholarships in Spain. ; Huang, Q.; Chen, N.; Liu, L.; Arias-Carrascal, KS.; Iborra Chornet, S.; Yi, X.; Ma, C. (2020). Direct synthesis of the organic and Ge free Al containing BOG zeolite (ITQ-47) and its application for transformation of biomass derived molecules. Chemical Science. 11(44):12103-12108. https://doi.org/10.1039/d0sc04044d ; S ; 12103 ; 12108 ; 11 ; 44 ; Cundy, C. S., & Cox, P. A. (2003). The Hydrothermal Synthesis of Zeolites: History and Development from the Earliest Days to the Present Time. Chemical Reviews, 103(3), 663-702. doi:10.1021/cr020060i ; C. Baerlocher and L. B.McCusker , Database of Zeolite Structures , http://www.iza-structure.org/databases/ , accessed June 8, 2018 ; Lobo, R. F., Pan, M., Chan, I., Medrud, R. C., ...

12103 12108 11 44 ; S ; [EN] Aluminosilicate boggsite (Si/Al-BOG) has been hydrothermally synthesized without adding org. structure-directing agents (OSDAs) in the synthesis gel using the borosilicogermanium ITQ-47 (Si/B-ITQ-47) zeolite as seeds. The introduction of the costly and environmentally less benign phosphazene org. structure-directing agent is not required to grow the zeolite. Physicochem. characterization expts. show that Si/Al-BOG has good crystallinity, high surface area, tetrahedral Al3+ species, and acid sites. In order to test the catalytic performance of the zeolite, the synthesis of L,L-lactide from L-lactic acid was performed. Si/Al-BOG exhibits 88.2% conversion of L-lactic acid and 83.8% L,L-lactide selectivity, which are better than those of other zeolites studied up to now. This work was supported by the National Natural Science Foundation of China 21971259 and 91645112, The Natural Science Foundation of Hubei Province of China (2014CFA043), and the Key Research Program of Frontier Sciences, CAS (No. QYZDB-SSW-SLH026). The European Union is also acknowledged by ERC-AdG-2014-671093 SynCatMatch, and the Spanish Government through "Severo Ochoa" (SEV-2016-0683, MINECO). Q. H. acknowledges the International Program Fund for doctoral students, Sun Yat-sen University, for scholarships in Spain. Huang, Q.; Chen, N.; Liu, L.; Arias-Carrascal, KS.; Iborra Chornet, S.; Yi, X.; Ma, C. (2020). Direct synthesis of the organic and Ge free Al containing BOG zeolite (ITQ-47) and its application for transformation of biomass derived molecules. Chemical Science. 11(44):12103-12108. https://doi.org/10.1039/d0sc04044d Cundy, C. S., & Cox, P. A. (2003). The Hydrothermal Synthesis of Zeolites: History and Development from the Earliest Days to the Present Time. Chemical Reviews, 103(3), 663-702. doi:10.1021/cr020060i C. Baerlocher and L. B.McCusker , Database of Zeolite Structures , http://www.iza-structure.org/databases/ , accessed June 8, 2018 Lobo, R. F., Pan, M., Chan, I., Medrud, R. C., Zones, S. I., ...