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[EN] Hybrid organic-inorganic catalysts have been extensively investigated by several research groups in the last decades, as they allow combining the structural robust-ness of inorganic solids with the versatility of organic chemistry. Within the field of hybrid catalysts, synthetic strategies based on silica are among the most exploitable, due to the convenience of sol-gel chemistry, to the array of silyl-derivative precursors that can be synthesized and to the number of post-synthetic functionalization strategies available, amongst others. This review proposes to highlight these advantages, firstly describing the most common synthetic tools and the chemistry behind sol-gel syntheses of hybrid catalysts, then presenting exemplificative studies involving mono- and multi-functional silica-based hybrid catalysts featuring different types of active sites (acid, base, redox). Materials obtained through different approaches are described and their properties, as well as their catalytic performances, are compared. The general scope of this review is to gather useful information for those approaching the synthesis of organic-inorganic hybrid materials, while providing an overview on the state-of-the art in the synthesis of such materials and highlighting their capacities. ; This research was funded by Spanish Government (MAT2017-82288-C2-1-P and Severo Ochoa Excellence Program SEV-2016-0683) and MULTY2HYCAT (EU-Horizon 2020 funded project under grant agreement no. 720783). ; Erigoni, A.; Díaz Morales, UM. (2021). Porous Silica-Based Organic-Inorganic Hybrid Catalysts: A Review. Catalysts. 11(1):1-39. https://doi.org/10.3390/catal11010079 ; S ; 1 ; 39 ; 11 ; 1

Hybrid organic-inorganic catalysts have been extensively investigated by several research groups in the last decades, as they allow combining the structural robust-ness of inorganic solids with the versatility of organic chemistry. Within the field of hybrid catalysts, synthetic strategies based on silica are among the most exploitable, due to the convenience of sol-gel chemistry, to the array of silylderivative precursors that can be synthesized and to the number of post-synthetic functionalization strategies available, amongst others. This review proposes to highlight these advantages, firstly describing the most common synthetic tools and the chemistry behind sol-gel syntheses of hybrid catalysts, then presenting exemplificative studies involving mono- and multi-functional silica-based hybrid catalysts featuring different types of active sites (acid, base, redox). Materials obtained through different approaches are described and their properties, as well as their catalytic performances, are compared. The general scope of this review is to gather useful information for those approaching the synthesis of organic-inorganic hybrid materials, while providing an overview on the state-of-the art in the synthesis of such materials and highlighting their capacities. ; This research was funded by Spanish Government (MAT2017-82288-C2-1-P and Severo Ochoa Excellence Program SEV-2016-0683) and MULTY2HYCAT (EU-Horizon 2020 funded project under grant agreement no. 720783). ; Peer reviewed

This document is the Accepted Manuscript version of a Published Work that appeared in final form in Chemistry of Materials, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://dx.doi.org/10.1021/cm070553+ ; [EN] Layered organic-inorganic hybrid materials were synthesized by pillaring with viologen and nitroaniline compounds which are intercalated between magadiite layers. The bridged silsesquioxanes, 4,4'-bis(trimethoxysilylpropyl)viologen and 4-nitro-N,N'-bis(3-trimethoxysilyl)propylaniline react with the surface silanol groups of the inorganic layers of silicate, bonding covalently with them. The preparation process was followed by DRX, and the pillarization was corroborated using chemical and thermogravimetrical analyses. The presence of viologen and nitroaniline organic linkers covalently bonded to inorganic layers was confirmed by C-13 and Si-29 NMR spectroscopy. UV-visible diffuse reflectance permitted to observe the high stabilization achieved by the intercalated organic fragments. Micro- and mesoporosity were also generated because of the existence of interlayer galleries conformed by homogenously distributed organic linkers into the interlayer space. The layered organic-inorganic hybrids exhibited a thermally stable network, and the organic spacers remained after elimination of the swelling agents by acid extraction. The resultant materials can be of interest as sensors and for nonlinear optics. ; Financial support by the Spanish Government (MAT-2006-14274-C02-01 and MAT2006-26599-E) and Universidad Polite´cnica de Valencia (PPI-06-05) is gratefully acknowledged. ; Díaz Morales, UM.; Cantin Sanz, A.; Corma Canós, A. (2007). Novel layered organic-inorganic hybrid materirals with bridged silsesquioxanes as Pillars. Chemistry of Materials. 19(15):3686-3693. https://doi.org/10.1021/cm070553+ ; S ; 3686 ; 3693 ; 19 ; 15

Light-emitting diodes (LEDs) based on organic-inorganic hybrid perovskites, in particular, 3D and quasi-2D ones, are in the fast development and their external quantum efficiencies (EQEs) have exceeded 10%, making them competitive candidates toward large-area and low-cost light-emitting applications allowing printing techniques. Similar to other LED categories, light out-coupling efficiency is an important parameter determining the EQE of perovskite LEDs (PeLEDs), which, however, is scarcely studied, limiting further efficiency improvement and understanding of PeLEDs. In this work, for the first time, optical energy losses in PeLEDs are investigated through systematic optical simulations, which reveal that the 3D and quasi-2D PeLEDs can achieve theoretically maximum EQEs of approximate to 25% and approximate to 20%, respectively, in spite of their high refractive indices. These results are consistent with the reported experimental data. This work presents primary understanding of the optical energy losses in PeLEDs and will spur new developments in the aspects of device engineering and light extraction techniques to boost the EQEs of PeLEDs. ; Funding Agencies|ERC [717026]; Carl Tryggers Stiftelse; European Commission [691210]; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [2009-00971]; National Basic Research Program of China [2016YFE0112000]; European Union [2016YFE0112000]; State Key Laboratory of Luminescent Materials and Devices at South China University of Technology [2017-skllmd-05]; State Key Lab of Silicon Materials at Zhejiang University [SKL2017-03]; China Scholarship Council [201506920047]; [2016-02051]

Abstract
In hybrid perovskite solar cells (PSCs), the reaction of hydrogens (H) located in the amino group of the organic A-site cations with their neighboring halides plays a central role in degradation. Inspired by the retarded biological activities of cells in heavy water, we replaced the light H atom with its abundant, twice-as-heavy, nonradioactive isotope, deuterium (D) to hamper the motion of H. This D substitution retarded the formation kinetics of the detrimental H halides in Pb-based PSCs, as well as the H bond-mediated oxidation of Sn2+ in Sn–Pb-based narrow-bandgap PSCs, evidenced by accelerated stability studies. A computational study indicated that the zero point energy of D-based formamidinium (FA) is lower than that of pristine FA. In addition, the smaller increase in entropy in D-based FA than in pristine FA accounts for the increased formation free energy of the Sn2+ vacancies, which leads to the retarded oxidation kinetics of Sn2+. In this study, we show that substituting active H with D in organic cations is an effective way to enhance the stability of PSCs without sacrificing photovoltaic (PV) performance. This approach is also adaptable to other stabilizing methods.

The design of new hybrid materials with tailored properties at the nano-, meso-, and macro-scale, with the use of structural functional nanobuilding units, is carried out to obtain specific multi-functional materials. Organization into controlled 1D, 2D, and 3D architectures with selected functionalities is key for developing advanced catalysts, but this is hardly accomplished using conventional synthesis procedures. The use of pre-formed nanostructures, derived either from known materials or made with specific innovative synthetic methodologies, has enormous potential in the generation of multi-site catalytic materials for one-pot processes. The present concept article introduces a new archetype wherein self-assembled nanostructured builder units are the base for the design of multifunctional catalysts, which combine catalytic efficiency with fast reactant and product diffusion. The article addresses a new generation of versatile hybrid organic-inorganic multi-site catalytic materials for their use in the production of (chiral) high-added-value products within the scope of chemicals and fine chemicals production. The use of those multi-reactive solids for more nanotechnological applications, such as sensors, due to the inclusion of electron donor-acceptor structural arrays is also considered, together with the adsorption-desorption capacities due to the combination of hydrophobic and hydrophilic sub-domains. The innovative structured hybrid materials for multipurpose processes here considered, can allow the development of multi-stage one-pot reactions with industrial applications, using the materials as one nanoreactor systems, favoring more sustainable production pathways with economic, environmental and energetic advantages. ; The authors are grateful for financial support from the Spanish Government by MAT2014‐52085‐C2‐1‐P and Severo Ochoa Excellence Program SEV‐2016‐0683. The European Union is also acknowledged by ERC‐AdG‐2014‐671093‐SynCatMatch.

Among the possible anti-corrosion preventive measures, galvanized steel reinforcement is usually employed to extend the service life of infrastructures in aggressive environments. Chromate conversion treatments have been employed as pre-treatments to reduce corrosion activity during the initial stages of contact of the reinforcing steel with the concrete alkaline environment, hindering the hydrogen evolution process during the formation of the protective layers on the surface of the galvanized steel. New environmentally friendly pre-treatments are however necessary since Cr(VI) is a carcinogen and its use is strongly restricted within the European Union [1]. The properties of organic-inorganic hybrid materials attracted significant attention over the past decades as a new class of materials through the novel properties that can arise from the combination of organic polymer and inorganic material and the production of hybrid protective thin coatings to apply on different metal substrates to prevent corrosion has been widely studied [2-4]. This class of materials could be easily obtained by sol-gel method at mild synthesis conditions and the large variety of available chemical precursors allows producing a diversity of coating materials with tuned mechanical and thermal properties. In this work a functionalized metal alkoxide (3-isocyanatopropyltriethoxysilane) and five oligopolymers (Jeffamine 130, 300, 600, 900 and 2000), identified as having potential to be used as an alternative pre-treatment to prevent the corrosion of galvanized steel in concrete, are tested as source of sol-gel precursors. Five hybrid matrix films were produced, doped with sodium dichromate acting as inhibitor. The coatings, doped and undoped with inhibitor, were applied using a single and a triple dip step. Dip-coating was done using a draw speed of 10 mm/min in both cases. Coatings resistance, with a minimum thickness, low permeability and high stability were evaluated by electrochemical studies, namely EIS (electrochemical impedance spectroscopy) and corrosion potential monitoring. The studies were carried out in Portland cement pastes and mortars. SEM/EDS analyses of the coatings were performed after 7, 14 and 28 days of exposure to the cement based materials ; FCT-PhD scholarship SFRH/BD/62601/2009 and Scholarships for Ph.D. students and young scientist - The GDCh Divisions of Applied Electrochemistry and Analytical Chemistry ; DM/NMM ; 2012 ; 17 a 19 de setembro