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This is the peer reviewed version of the following article: Angew. Chem. Int. Ed. 2018, 57, 15330 15353, which has been published in final form at https://doi.org/10.1002/anie.201711422. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. ; [EN] Since the early reports by Barrer in the 1940s on converting natural minerals into synthetic zeolites, the use of precrystallized zeolites as crucial inorganic directing agents to synthesize other crystalline zeolites with improved physicochemical properties has become a very important research field, allowing the design, particularly in recent years, of new industrial catalysts. This Review highlights how the presence of some crystalline fragments in the synthesis media, such as small secondary building units (SBUs) or layered substructures, not only favors the crystallization of other zeolites with similar SBUs or layers, but also permits control over important parameters affecting their catalytic activity (chemical composition, crystal size, or porosity, etc.). Recent advances in the preparation of 3D and 2D zeolites through seeding and zeolite-to-zeolite transformation processes will be discussed extensively in this Review, including their preparation in the presence or absence of organic structure-directing agents (OSDAs). The aim is to introduce general guidelines for more efficient approaches for target zeolites. ; This work has been supported by the Spanish Government (MINECO through "Severo Ochoa" (SEV-2016-0683) and MAT2015-71261-R), by the European Union through ERC-AdG-2014-671093 (SynCatMatch), and by the Fundacion Ramon Areces (through the "Life and Materials Science" program). ; Li, C.; Moliner Marin, M.; Corma Canós, A. (2018). Building zeolites from precrystallized units: nanoscale architecture. Angewandte Chemie International Edition. 57(47):15330-15353. https://doi.org/10.1002/anie.201711422 ; S ; 15330 ; 15353 ; 57 ; 47 ; Cundy, C. S., & Cox, P. A. (2005). The hydrothermal ...

15330 15353 57 47 ; S Moliner, M., Martínez, C., & Corma, A. (2015). Multiporige Zeolithe: Synthese und Anwendungen bei der Katalyse. Angewandte Chemie, 127(12), 3630-3649. doi:10.1002/ange.201406344 Moliner, M., Rey, F., & Corma, A. (2013). Rationales Design von effizienten organischen strukturdirigierenden Reagentien für die Zeolithsynthese. Angewandte Chemie, 125(52), 14124-14134. doi:10.1002/ange.201304713 Jiang, J., Yu, J., & Corma, A. (2010). Zeolithe mit sehr großen Poren als Bindeglied zwischen mikro- und mesoporösen Strukturen. Angewandte Chemie, 122(18), 3186-3212. doi:10.1002/ange.200904016 C. T.Kresge W. J.Roth U.S. Patent 5266541 1993. S. I.Zones US 4544538 1985. T. V.Whittam US Pat 4397825 1983. Corma, A., Puche, M., Rey, F., Sankar, G., & Teat, S. J. (2003). Angewandte Chemie, 115(10), 1188-1191. doi:10.1002/ange.200390275 A. W.Burton WO2014/099261 2014; ; D.Xie WO2016/122724 2016. ; 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 ; S. I.Zones Y.Nakagawa S. T.Evans G. S.Lee US 5958370 1999; ; This is the peer reviewed version of the following article: Angew. Chem. Int. Ed. 2018, 57, 15330 15353, which has been published in final form at https://doi.org/10.1002/anie.201711422. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. [EN] Since the early reports by Barrer in the 1940s on converting natural minerals into synthetic zeolites, the use of precrystallized zeolites as crucial inorganic directing agents to synthesize other crystalline zeolites with improved physicochemical properties has become a very important research field, allowing the design, particularly in recent years, of new industrial catalysts. This Review highlights how the presence of some crystalline fragments in the synthesis media, such as small secondary building units (SBUs) or layered substructures, not ...

By combining kinetics and theoretical calculations, we show here the benefits of going beyond the concept of static localized and defined active sites on solid catalysts, into a system that globally and dynamically considers the active site located in an environment that involves a scaffold structure particularly suited for a target reaction. We demonstrate that such a system is able to direct the reaction through a preferred mechanism when two of them are competing. This is illustrated here for an industrially relevant reaction, the diethylbenzene-benzene transalkylation. The zeolite catalyst (ITQ-27) optimizes location, density, and environment of acid sites to drive the reaction through the preselected and preferred diaryl-mediated mechanism, instead of the alkyl transfer pathway. This is achieved by minimizing the activation energy of the selected pathway through weak interactions, much in the way that it occurs in enzymatic catalysts. We show that ITQ-27 outperforms previously reported zeolites for the DEB-Bz transalkylation and, more specifically, industrially relevant zeolites such as faujasite, beta, and mordenite. ; This work was supported by the European Union through ERC-AdG-2014-671093 (SynCatMatch), Spanish Government through "Severo Ochoa" (SEV-2016-0683, MINECO), MAT2017-82288-C2-1-P (AEI/FEDER, UE) and RTI2018-101033-B-I00 (MCIU/AEI/FEDER, UE), and by Generalitat Valenciana through AICO/2019/060. T

[EN] Controlling the location of acid sites in zeolites can have a great effect on catalysis. In this work we face the objective of directing the location of AI into the 10R channels of ZSM-5 by taking advantage of the structural preference of B to occupy certain positions at the channel intersections, as suggested by theoretical calculations. The synthesis of B-Al-ZSM-5 zeolites with variable Si/Al and Si/B ratios, followed by B removal in a postsynthesis treatment, produces ZSM-5 samples enriched in Al occupying positions at 10R channels. The location of the acid sites is determined on the basis of the product distribution of 1-hexene cracking as a test reaction. The higher selectivity to propene and lower C-4(=)/C-3(=) ratio in the samples synthesized with B and subsequently deboronated can be related to a larger concentration of acid sites in 10R channels, where monomolecular cracking occurs. Finally, several ZSM-5 samples have been tested in the methanol to propene reaction, and those synthesized through the B -assisted method show longer catalytic lifetime, higher propene yield, and lower yield of alkanes and aromatics. ; This work was supported by the European Union through ERC-AdG-2014-671093 (SynCatMatch) and the Spanish Government-MINECO through "Severo Ochoa" (SEV-2016-0683) and CTQ2015-70126-R. The Electron Microscopy Service of the UPV is acknowledged for their help in sample characterization. Red Espanola de Supercomputacion (RES) and Centre de Calcul de la Universitat de Valencia are gratefully acknowledged for computational resources and technical support. C.L. acknowledges the China Scholarship Council (CSC) for a Ph.D. fellowship ; Li, C.; Vidal Moya, JA.; Miguel, PJ.; Dedecek, J.; Boronat Zaragoza, M.; Corma Canós, A. (2018). Selective Introduction of Acid Sites in Different Confined Positions in ZSM-5 and Its Catalytic Implications. ACS Catalysis. 8(8):7688-7697. https://doi.org/10.1021/acscatal.8b02112 ; S ; 7688 ; 7697 ; 8 ; 8 ; Brand, H. V., Curtiss, L. A., & Iton, L. E. (1993). Ab ...

Subnanometric metal species (single atoms and clusters) have been demonstrated to be unique compared with their nanoparticulate counterparts. However, the poor stabilization of subnanometric metal species towards sintering at high temperature (>500 °C) under oxidative or reductive reaction conditions limits their catalytic application. Zeolites can serve as an ideal support to stabilize subnanometric metal catalysts, but it is challenging to localize subnanometric metal species on specific sites and modulate their reactivity. We have achieved a very high preference for localization of highly stable subnanometric Pt and PtSn clusters in the sinusoidal channels of purely siliceous MFI zeolite, as revealed by atomically resolved electron microscopy combining high-angle annular dark-field and integrated differential phase contrast imaging techniques. These catalysts show very high stability, selectivity and activity for the industrially important dehydrogenation of propane to form propylene. This stabilization strategy could be extended to other crystalline porous materials. ; This work has been supported by the European Union through the European Research Council (grant ERC-AdG-2014-671093, SynCatMatch) and the Spanish government through the Severo Ochoa Programme (SEV-2016-0683). L.L. thanks ITQ for providing a contract. The authors also thank the Microscopy Service of UPV for the TEM and STEM measurements. The XAS measurements were carried out in CLAESS beamline at the ALBA synchrotron. HR STEM measurements were performed at DME-UCA in Cadiz University with financial support from FEDER/MINECO (MAT2017-87579-R and MAT2016-81118-P). A relevant patent application (European patent application No. 19382024.8) has been presented. C.W.L. thanks CAPES (Science without Frontiers-Process no. 13191/13-6) for a predoctoral fellowship.

This is the peer reviewed version of the following article: P. Ferri, C. Li, C. Paris, A. Rodríguez-Fernández, M. Moliner, M. Boronat, A. Corma, ChemCatChem 2021, 13, 1578, which has been published in final form at https://doi.org/10.1002/cctc.202001760. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. ; [EN] The light olefin product distribution of the methanol-to-olefin (MTO) reaction catalyzed by acid zeolites and zeotypes depends on the nature of the entrapped hydrocarbon pool species that act as co-catalysts. The preferential stabilization by confinement effects of the cationic intermediates involved in the side-chain or paring pathways of the aromatics-based cycle of the MTO mechanism in small-pore cage-based zeolites is determined by the topology of the cavity, and can be quantitatively described through the E-int(7/5) parameter obtained from DFT calculations. In this work we extend the study of the E-int(7/5) parameter to a wide range of structures (ERI, LEV, AEI, CHA, DDR, AFX, RTH, ITE, SAV, UFI, RHO, KFI, and LTA) and discuss its applicability in small cages with steric constraints to host bulky intermediates, in zeolites with a tight fitting between the cavity and the hosted cations, and in large cages where confinement effects are lost in part and competitive processes occur. ; This work has been supported by the European Union through ERC-AdG-2014-671093 (SynCatMatch), Spanish Government through ''Severo Ochoa" (SEV-2016-0683, MINECO), MAT2017-82288-C2-1-P (AEI/FEDER, UE) and RTI2018-101033-B-I00 (MCIU/AEI/FEDER, UE), and by Generalitat Valenciana through AICO/2019/060. The Electron Microscopy Service of the UPV is acknowledged for their help in sample characterization. Red Espanola de Supercomputacion (RES) and Servei d'Informatica de la Universitat de Valencia (SIUV) are acknowledged for computational resources and technical support. P.F. and C.L. thank ITQ for their contracts. A.R.F. acknowledges the Spanish Government-MINECO ...

This is the peer reviewed version of the following article: P. Ferri, C. Li, R. Millán, J. Martínez-Triguero, M. Moliner, M. Boronat, A. Corma, Angew. Chem. Int. Ed. 2020, 59, 19708, which has been published in final form at https://doi.org/10.1002/anie.202007609. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. ; [EN] The methanol-to-olefins reaction catalyzed by small-pore cage-based acid zeolites and zeotypes produces a mixture of short chain olefins, whose selectivity to ethene, propene and butene varies with the cavity architecture and with the framework composition. The product distribution of aluminosilicates and silicoaluminophosphates with the CHA and AEI structures (H-SSZ-13, H-SAPO-34, H-SSZ-39 and H-SAPO-18) has been experimentally determined, and the impact of acidity and framework flexibility on the stability of the key cationic intermediates involved in the mechanism and on the diffusion of the olefin products through the8rwindows of the catalysts has been evaluated by means of periodic DFT calculations and ab initio molecular dynamics simulations. The preferential stabilization by confinement of fully methylated hydrocarbon pool intermediates favoring the paring pathway is the main factor controlling the final olefin product distribution. ; This work has been supported by the European Union through ERC-AdG-2014-671093 (SynCatMatch), Spanish Government through "Severo Ochoa" (SEV-2016-0683, MINECO), MAT2017-82288-C2-1-P (AEI/FEDER, UE) and RTI2018-101033-B-I00 (MCIU/AEI/FEDER, UE), and by Generalitat Valenciana through AICO/2019/060. The Electron Microscopy Service of the UPV is acknowledged for their help in sample characterization. Red Espanola de Supercomputacion (RES) and Servei d'Informatica de la Universitat de Valencia (SIUV) are acknowledged for computational resources and technical support. P.F. and R.M. thank ITQ for their contracts. C.L. acknowledges China Scholarship Council (CSC) for a Ph.D fellowship. ...

"This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Catalysis, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acscatal.9b04588" ; [EN] The catalysts used in the methanol-to-olefins (MTO) reaction are considered dual systems comprising an inorganic zeolite framework and organic compounds hosted inside that act as cocatalysts. The influence of zeolite cavity architecture on the preferential stabilization of cationic intermediates involved in the paring and side-chain routes of the hydrocarbon pool mechanism is analyzed by means of density functional theory (DFT) calculations, catalyst testing, and C-13 NMR spectroscopy for some small-pore cage-based zeolites. A correlation between the degree of methylation of the entrapped methylbenzenium (MB+) cations and the selectivity to ethene and propene is found experimentally and explained in terms of the electronic distribution of the first intermediate of the paring route. A deep understanding of the reaction mechanism and of the specific host guest interactions taking place inside zeolite catalysts allows establishing a quantitative parameter that is indicative for the contribution of the paring route and therefore the C-3(=)/C-2(=) ratio in the MTO reaction. ; This work has been supported by the European Union through ERC-AdG-2014-671093 (SynCatMatch), Spanish Government through "Severo Ochoa" (SEV-2016-0683, MINECO), MAT2017-82288-C2-1-P (AEI/FEDER, UE), and RTI2018-101033-B-100 (MCIU/AEI/FEDER, UE), and by the Fundacion Ramon Areces through a research contract (CIVP18A3908). The Electron Microscopy Service of the UPV is acknowledged for their help in sample characterization. Red Espanola de Supercomputacion (RES) and Servei d'Informatica de la Universitat de Valencia are acknowledged for computational resources and technical support. C.L. acknowledges the China Scholarship Council (CSC) for a ...

[EN] Subnanometric metal species (single atoms and clusters) have been demonstrated to be unique compared with their nanoparticulate counterparts. However, the poor stabilization of subnanometric metal species towards sintering at high temperature (>500 degrees C) under oxidative or reductive reaction conditions limits their catalytic application. Zeolites can serve as an ideal support to stabilize subnanometric metal catalysts, but it is challenging to localize subnanometric metal species on specific sites and modulate their reactivity. We have achieved a very high preference for localization of highly stable subnanometric Pt and PtSn clusters in the sinusoidal channels of purely siliceous MFI zeolite, as revealed by atomically resolved electron microscopy combining high-angle annular dark-field and integrated differential phase contrast imaging techniques. These catalysts show very high stability, selectivity and activity for the industrially important dehydrogenation of propane to form propylene. This stabilization strategy could be extended to other crystalline porous materials. ; This work has been supported by the European Union through the European Research Council (grant ERC-AdG-2014-671093, SynCatMatch) and the Spanish government through the Severo Ochoa Programme (SEV-2016-0683). L.L. thanks ITQ for providing a contract. The authors also thank the Microscopy Service of UPV for the TEM and STEM measurements. The XAS measurements were carried out in CLAESS beamline at the ALBA synchrotron. HR STEM measurements were performed at DME-UCA in Cadiz University with financial support from FEDER/MINECO (MAT2017-87579-R and MAT2016-81118-P). A relevant patent application (European patent application No. 19382024.8) has been presented. C.W.L. thanks CAPES (Science without Frontiers-Process no. 13191/13-6) for a predoctoral fellowship. ; Liu, L.; Lopez-Haro, M.; Lopes, CW.; Li, C.; Concepción Heydorn, P.; Simonelli, L.; Calvino, JJ. (2019). Regioselective generation and reactivity control of subnanometric ...

866 875 18 8 ; S ; [EN] Subnanometric metal species (single atoms and clusters) have been demonstrated to be unique compared with their nanoparticulate counterparts. However, the poor stabilization of subnanometric metal species towards sintering at high temperature (>500 degrees C) under oxidative or reductive reaction conditions limits their catalytic application. Zeolites can serve as an ideal support to stabilize subnanometric metal catalysts, but it is challenging to localize subnanometric metal species on specific sites and modulate their reactivity. We have achieved a very high preference for localization of highly stable subnanometric Pt and PtSn clusters in the sinusoidal channels of purely siliceous MFI zeolite, as revealed by atomically resolved electron microscopy combining high-angle annular dark-field and integrated differential phase contrast imaging techniques. These catalysts show very high stability, selectivity and activity for the industrially important dehydrogenation of propane to form propylene. This stabilization strategy could be extended to other crystalline porous materials. This work has been supported by the European Union through the European Research Council (grant ERC-AdG-2014-671093, SynCatMatch) and the Spanish government through the Severo Ochoa Programme (SEV-2016-0683). L.L. thanks ITQ for providing a contract. The authors also thank the Microscopy Service of UPV for the TEM and STEM measurements. The XAS measurements were carried out in CLAESS beamline at the ALBA synchrotron. HR STEM measurements were performed at DME-UCA in Cadiz University with financial support from FEDER/MINECO (MAT2017-87579-R and MAT2016-81118-P). A relevant patent application (European patent application No. 19382024.8) has been presented. C.W.L. thanks CAPES (Science without Frontiers-Process no. 13191/13-6) for a predoctoral fellowship. Liu, L.; Lopez-Haro, M.; Lopes, CW.; Li, C.; Concepción Heydorn, P.; Simonelli, L.; Calvino, JJ. (2019). Regioselective generation and reactivity control of ...

[EN] From theoretical calculations and a rational synthesis methodology, it has been possible to prepare nanocrystalline (60-80 nm) chabazite with an optimized framework Al distribution that has a positive impact on its catalytic properties. This is exemplified for the methanol-to-olefin (MTO) process. The nanosized material with the predicted Al distribution maximizes the formation of the required MTO hydrocarbon pool intermediates, while better precluding excessive diffusion pathways that favor the rapid catalyst deactivation by coke formation. ; This work has been supported by the EU through ERC-AdG-2014-671093, by the Spanish Government-MINECO through "Severo Ochoa" (SEV-2016-0683) and MAT2015-71261-R, and by the Fundacion Ramon Areces through a research contract of the "Life and Materials Science" program. E.M.G. acknowledges "La Caixa-Severo Ochoa" International PhD Fellowships (call 2015), C.L. acknowledges China Scholarship Council (CSC) for a Ph.D fellowship, and N.M. thanks MINECO for a pre-doctoral fellowship (BES-2013-064347). Red Espanola de Supercomputacion (RES) and Centre de Calcul de la Universitat de Valencia are gratefully acknowledged for computational resources. ; Gallego-Sánchez, EM.; Li, C.; Paris, C.; Martín-García, N.; Martínez-Triguero, J.; Boronat Zaragoza, M.; Moliner Marin, M. (2018). Making Nanosized CHA Zeolites with Controlled Al Distribution for Optimizing Methanol-to-Olefin Performance. Chemistry - A European Journal. 24(55):14631-14635. https://doi.org/10.1002/chem.201803637 ; S ; 14631 ; 14635 ; 24 ; 55 ; Tian, P., Wei, Y., Ye, M., & Liu, Z. (2015). Methanol to Olefins (MTO): From Fundamentals to Commercialization. ACS Catalysis, 5(3), 1922-1938. doi:10.1021/acscatal.5b00007 ; Olsbye, U., Svelle, S., Bjørgen, M., Beato, P., Janssens, T. V. W., Joensen, F., … Lillerud, K. P. (2012). Conversion of Methanol to Hydrocarbons: How Zeolite Cavity and Pore Size Controls Product Selectivity. Angewandte Chemie International Edition, 51(24), 5810-5831. doi:10.1002/anie.201103657 ...