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Agency: European Commission | Branch: H2020 | Program: IA | Phase: NMP-03-2015 | Award Amount: 7.94M | Year: 2016

The main idea of POROUS4APP project is based on the fabrication of functional nanoporous carbonaceous materials at pilot plant scale from natural resources (polysaccharide). The process for nanoporous carbon fabrication is already well known as one of the POROUS4APP partner has developed the STARBON technology at TRL5 which consist of swelling, drying and pyrolysis of natural resources and in this case Starch. What POROUS4APP project will bring to the European community is the development of new metal/metal-oxide doped-nanoporous carbonaceous materials based on a known technology. This technology needs to be upscaled and modified to enable a full flexibility of the material characteristics to be applied to various industrial applications. The use of abundant renewable resources like starch has been proven to be a low cost and reliable raw material source for industrial production of carbonaceous materials having porosity in the nanometer range. In POROUS4APP it will be intended to produce not only carbonaceous nanoporous materials but carbonaceous material with enhanced functionality by using impregnation and sol/gel strategy. This will allow POROUS4APP materials to reach the challenging requirements of state of the art high added value materials at lower cost for applications in energy storage such as lithium-ion battery and also in chemical catalysis process. These applications need materials with well defined porosity to reach high efficiency level of their functional systems.

Agency: European Commission | Branch: H2020 | Program: RIA | Phase: NMBP-03-2016 | Award Amount: 4.48M | Year: 2017

CREATE aims at developing innovative membrane electrode assemblies for low-temperature polymer-electrolyte fuel cell (FC) and electrolyzer (EL) with much reduced cost. This will be achieved via elimination or drastic reduction of critical raw materials in their catalysts, in particular platinum group metals (PGM). Key issues with present low-temperature FC & EL are the high contents of PGM in devices based on proton-exchange-membrane (PEM) and the need for liquid electrolytes in alkaline FC and EL. To overcome this, we will shift from PEM-based cells to 1) pure anion-conducting polymer-electrolytes and 2) to bipolar-membrane polymer electrolytes. The latter comprises anion and proton conducting ionomers and a junction. Bipolar membranes allow adapting the pH at each electrode, thereby opening the door to improved performance or PGM-free catalysts. Both strategies carry the potentiality to eliminate or drastically reduce the need for PGM while maintaining the advantages of PEM-based devices. In strategy 1, novel anion-exchange ionomers and membranes will be developed and interfaced with catalysts based on Earth-abundant metal oxides or metal-carbon composites for the oxygen reactions, and with ultralow PGM or PGM-free catalysts for the hydrogen reactions. In strategy 2, novel bipolar membrane designs, or designs unexplored for FC & EL, will be developed and interfaced with catalysts for the oxygen reactions (high pH side of the bipolar membrane) and with catalysts for the hydrogen reactions (low pH side). The ionomers and oxygen reaction catalysts developed in strategy 1 will be equally useful for strategy 2, while identified PGM-free and ultralow-PGM catalysts will be implemented for the hydrogen reactions on the acidic side. Polymer-electrolyte FC & EL based on those concepts will be evaluated for targeted applications, i.e. photovoltaic electricity storage, off-grid back-up power and H2 production. The targeted market is distributed small-scale systems.

Agency: European Commission | Branch: H2020 | Program: RIA | Phase: FETPROACT-01-2016 | Award Amount: 7.98M | Year: 2017

A novel concept for a photo-electro-catalytic (PEC) cell able to directly convert water and CO2 into fuels and chemicals (CO2 reduction) and oxygen (water oxidation) using exclusively solar energy will be designed, built, validated, and optimized. The cell will be constructed from cheap multifunction photo-electrodes able to transform sun irradiation into an electrochemical potential difference (expected efficiency > 12%); ultra-thin layers and nanoparticles of metal or metal oxide catalysts for both half-cell reactions (expected efficiency > 90%); and stateof- the-art membrane technology for gas/liquid/products separation to match a theoretical target solar to fuels efficiency above 10%. All parts will be assembled to maximize performance in pH > 7 solution and moderate temperatures (50-80 C) as to take advantage of the high stability and favorable kinetics of constituent materials in these conditions. Achieving this goal we will improve the state-of-the-art of all components for the sake of cell integration: 1) Surface sciences: metal and metal oxide catalysts (crystals or nanostructures grown on metals or silicon) will be characterized for water oxidation and CO2 reduction through atomically resolved experiments (scanning probe microscopy) and spatially-averaged surface techniques including surface analysis before, after and in operando electrochemical reactions. Activity and performance will be correlated to composition, thickness, structure and support as to determine the optimum parameters for device integration. 2) Photoelectrodes: This unique surface knowledge will be transferred to the processing of catalytic nanostructures deposited on semiconductors through different methods to match the surface chemistry results through viable up-scaling processes. Multiple thermodynamic and kinetic techniques will be used to characterize and optimize the performance of the interfaces with spectroscopy and photo-electrochemistry tools to identify best matching between light absorbers and chemical catalysts along optimum working conditions (pH, temperature, pressure). 3) Modeling: Materials, catalysts and processes will be modeled with computational methods as a pivotal tool to understand and to bring photo-catalytic-electrodes to their theoretical limits in terms of performance. The selected optimum materials and environmental conditions as defined from these parallel studies will be integrated into a PEC cell prototype. This design will include ion exchange membranes and gas diffusion electrodes for product separation. Performance will be validated in real working conditions under sun irradiation to assess the technological and industrial relevance of our A-LEAF cell.

Agency: European Commission | Branch: H2020 | Program: MSCA-ITN-ETN | Phase: MSCA-ITN-2016 | Award Amount: 3.63M | Year: 2016

The global need to move current human technologies into a sustainable future will have a great impact for the world of chemistry and related industries. In close concert with other disciplines, chemistry will be increasingly solicited to identify solutions that are practical, affordable and ultimately sustainable. To meet these objectives, not only research, but also chemical education will need profound reforms that have to be contextualized in the multidisciplinary and intersectoral picture of a sustainable development. It is propelled by these societal needs that, by educating and practising 14 ESRs, PHOTOTRAIN will ensure photo-triggered chemical process to play its central role in sustainability. By capitalising on the basic principles of supramolecular chemistry to program dynamic self-organized photoactive interfaces, it is intended to raise the creativity, knowledge, skills and capacity of the ESRs to conceive new ideas for reforming current industrial transformations into a new generation of light-triggered processes. The challenge of developing and transferring light-fuelled processes from a proof-of-principle to an exploitable process is to embark upon a dynamic configuration in which photoactive species are kept separated, act independently and are finally recycled. In particular, through the adoption of a microfluidic system in which programmed different phases allow the formation of photoactive interfaces, it is planned to implement photo-catalytic technologies at the industrial level for triggering stereoselective organocatalytic transformations (i.e., pharmaceutical applications) and/or solar fuels production. By the organisation of targeted individual projects and interdisciplinary secondements, ESRs will be guided toward attractive early-stage career opportunities as researchers, process chemists, chemical engineers and research managers in collective forms at various academic and research institutes, small and large enterprises, and NGOs.

Ballester P.,Institute of Chemical Research of Catalonia | Ballester P.,Catalan Institution for Research and Advanced Studies
Accounts of Chemical Research | Year: 2013

Chemical intuition suggests that anions and π-aromatic systems would repel each other. Typically, we think of cations as being attracted to electron-rich π-systems of aromatic rings, and the cation-π interaction, a well-established noncovalent interaction, plays an important role in nature. Therefore the anion-π interaction can be considered the opposite of the cation-π interaction. Computational studies of simple models of anion-π interactions have provided estimates of the factors that govern the binding geometry and the binding energy, leading to a general consensus about the nature of these interactions. In order to attract an anion, the charge distribution of the aromatic system has to be reversed, usually through the decoration of the aromatic systems with strongly electron-withdrawing groups. Researchers have little doubt about the existence of attractive anion-π interactions in the gas phase and in the solid state. The bonding energies assigned to anion-π interactions from quantum chemical calculations and gas phase experiments are significant and compare well with the values obtained for cation-π interactions. In solution, however, there are few examples of attractive anion-π interactions.In this Account, I describe several examples of neutral molecular receptors that bind anions in solution either solely through anion-π interactions or as a combination of anion-π interactions and hydrogen bonding. In the latter cases, the strength of the anion-π interaction is indirectly detected as a modulation of the stronger hydrogen bonding interaction (enforced proximity). The dissection of the energy contribution of the anion-π interaction to the overall binding is complex, which requires the use of appropriate reference systems.This Account gives an overview the experimental efforts to determine the binding energies that can be expected from anion-π interactions in solution with examples that center around the recognition of halides. The studies show that anion-π interactions also exist in solution, and the free energy of binding estimated for these attractive interactions is less than 1 kcal/mol for each substituted phenyl groups. The quantification of anion-π interactions in solution relies on the use of molecular recognition model systems; therefore researchers need to consider how the structure of the model system can alter the magnitude of the observed energy values. In addition, the recognition of anions in solution requires the use of salts (ion pairs) as precursors, which complicates the analysis of the titration data and the corresponding estimate of the binding strength. In solution, the weak binding energies suggest that anion-π interactions are not as significant for the selective or enhanced binding of anions but offer potential applications in catalysis and transport within functional synthetic and biological systems. © 2012 American Chemical Society.

Tomashenko O.A.,Institute of Chemical Research of Catalonia | Grushin V.V.,Institute of Chemical Research of Catalonia
Chemical Reviews | Year: 2011

Since the discovery of the McLoughlin-Thrower reaction in 1960s, considerable progress has been made in the important, demand-driven area of metal-promoted and metal-catalyzed aromatic trifluoromethylation. Important advancements have also been made in the development of Cu-catalyzed trifluoromethylations, and Ar-CF3 bond formation with well defined Cu(I) complexes. Although in some cases aryl bromides can be successfully used in Cu-mediated perfluoroalkylation reactions, iodoarenes are much more preferred due to their enhanced reactivity. Palladium is incomparably more costly than copper. Therefore, a utilizable nucleophilic aromatic trifluoromethylation process based on Pd must use catalytic, minimal quantities of this precious metal. Furthermore, many ligands employed in various Pd-catalyzed reactions often cost more than the metal itself. Another problem associated with the development of new ligands for Pd-catalyzed trifluoromethylation reactions is the facile transmetalation reaction.

Obradors C.,Institute of Chemical Research of Catalonia | Echavarren A.M.,Institute of Chemical Research of Catalonia
Accounts of Chemical Research | Year: 2014

Cycloisomerizations of enynes are probably the most representative carbon-carbon bond forming reactions catalyzed by electrophilic metal complexes. These transformations are synthetically useful because chemists can use them to build complex architectures under mild conditions from readily assembled starting materials. However, these transformations can have complex mechanisms. In general, gold(I) activates alkynes in the presence of any other unsaturated functional group by forming an (η2-alkyne)-gold complex. This species reacts readily with nucleophiles, including electron-rich alkenes. In this case, the reaction forms cyclopropyl gold(I) carbene-like intermediates. These can come from different pathways depending on the substitution pattern of the alkyne and the alkene. In the absence of external nucleophiles, 1,n-enynes can form products of skeletal rearrangement in fully intramolecular reactions, which are mechanistically very different from metathesis reactions initiated by the [2 + 2] cycloaddition of a Grubbs-type carbene or other related metal carbenes.In this Account, we discuss how cycloisomerization and addition reactions of substituted enynes, as well as intermolecular reactions between alkynes and alkenes, are best interpreted as proceeding through discrete cationic intermediates in which gold(I) plays a significant role in the stabilization of the positive charge. The most important intermediates are highly delocalized cationic species that some chemists describe as cyclopropyl gold(I) carbenes or gold(I)-stabilized cyclopropylmethyl/cyclobutyl/homoallyl carbocations. However, we prefer the cyclopropyl gold(I) carbene formulation for its simplicity and mnemonic value, highlighting the tendency of these intermediates to undergo cyclopropanation reactions with alkenes.We can add a variety of hetero- and carbonucleophiles to the enynes in the presence of gold(I) in intra- or intermolecular reactions, leading to the corresponding adducts with high stereoselectivity through stereospecific anti-additions. We have also developed stereospecific syn-additions, which probably occur through similar intermediates. The attack of carbonyl groups at the cyclopropyl carbons of the intermediate cyclopropyl gold(I) carbenes initiates a particularly interesting group of reactions. These trigger a cascade transformation that can lead to the formation of two C-C and one C-O bonds. In the fully intramolecular process, this stereospecific transformation has been applied for the synthesis of natural sesquiterpenoids such as (+)-orientalol F and (-)-englerin A.Intra- and intermolecular trapping of cyclopropyl gold(I) carbenes with alkenes leads to the formation of cyclopropanes with significant increase in the molecular complexity, particularly in cases in which this process combines with the migration of propargylic alkoxy and related OR groups. We have recently shown this in the stereoselective total synthesis of the antiviral sesquiterpene (+)-schisanwilsonene by a cyclization/1,5-acetoxy migration/intermolecular cyclopropanation. In this synthesis, the cyclization/1,5-acetoxy migration is faster than the alternative 1,2-acyloxy migration that would result in racemization. © 2013 American Chemical Society.

Ballester P.,Institute of Chemical Research of Catalonia
Chemical Society Reviews | Year: 2010

This critical review describes selected examples extracted from the extensive literature generated during the past 42 years on the topic of anion binding in molecular capsules. The goal of including anions in molecular capsules emerges from the idea of incorporating the traits exhibited by biological receptors into synthetic ones. At the outset of this research area the capsules were unimolecular. The scaffold of the receptor was designed to covalently link a series of functional groups that could converge into a cavity and to avoid its collapse. The initial examples involved the encapsulation of one monoatomic spherical anion. With time, the cavity size of the receptor was increased and encapsulation of polyatomic anions and co-encapsulation became a reality. Synthetic economy fueled the use of aggregates of self-complementary molecules rather than one large molecule as capsules. The main purpose of this review is to give a general overview of the topic which might be of interest to supramolecular or non supramolecular chemists alike (149 references). © 2010 The Royal Society of Chemistry.

Agency: European Commission | Branch: H2020 | Program: ERC-COG | Phase: ERC-CoG-2015 | Award Amount: 2.00M | Year: 2016

Visible light photocatalysis and metal-free organocatalytic processes are powerful strategies of modern chemical research with extraordinary potential for the sustainable preparation of organic molecules. However, these environmentally respectful approaches have to date remained largely unrelated. The proposed research seeks to merge these fields of molecule activation to redefine their synthetic potential. Light-driven processes considerably enrich the modern synthetic repertoire, offering a potent way to build complex organic frameworks. In contrast, it is extremely challenging to develop asymmetric catalytic photoreactions that can create chiral molecules with a well-defined three-dimensional arrangement. By developing innovative methodologies to effectively address this issue, I will provide a novel reactivity framework for conceiving light-driven enantioselective organocatalytic processes. I will translate the effective tools governing the success of ground state asymmetric organocatalysis into the realm of photochemical reactivity, exploiting the potential of key organocatalytic intermediates to directly participate in the photoexcitation of substrates. At the same time, the chiral organocatalyst will ensure effective stereochemical control. This single catalyst system, where stereoinduction and photoactivation merge in a sole organocatalyst, will serve for developing novel enantioselective photoreactions. In a complementary dual catalytic approach, the synergistic activities of an organocatalyst and a metal-free photosensitiser will combine to realise asymmetric variants of venerable photochemical processes, which have never before succumbed to a stereocontrolled approach. This proposal challenges the current perception that photochemistry is too unselective to parallel the impressive levels of efficiency reached by the asymmetric catalysis of thermal reactions, expanding the way chemists think about making chiral molecules.

Agency: European Commission | Branch: H2020 | Program: ERC-COG | Phase: ERC-CoG-2014 | Award Amount: 2.00M | Year: 2015

The development of alternative greener synthetic methods to transform renewable feedstocks into elaborated chemical structures mediated by solar light is a prerequisite for a future sustainable society. In this regard, this project entails the use of visible light as driving force and water as a source of hydrides for the synthesis of high-value chemicals. The project merges photoredox catalysis with 1st row transition coordination complexes catalysis to open a new avenue for greener selective catalytic reduction processes for organic substrates. The ground-breaking nature of the project is: A) Develop light-driven region- and/or enantioselective catalytic reductions using well-defined cobalt coordination complexes with aminopyridine ligands, initially developed for water reduction. Sterics, electronics and supramolecular interactions (apolar cavities and chiral pockets) will be studied to proper control of the selectivity in the reduction of i) C=E and C=C bonds and ii) in the C-C inter- and intramolecular reductive homo- or heterocouplings. B) Fundamental understanding of the light-driven cobalt catalysed reductions characterizing intermediates that are involved in the reactivity, kinetics and labelling studies as well as performing computational modelling of reaction mechanisms. The basic understanding of operative mechanisms will expedite a new methodology for electrophile-electrophile umpolung couplings. C) Enhance catalytic performance of the light-driven cobalt catalysed reductions by self-assembling of catalyst-photosensitizer into carbon based pi-conjugated materials through noncovalent supramolecular interactions. Likewise, it will allow electrode immobilization for electrocatalysed reductions using water as a source of protons and electrons. As a proof of concept, cobalt catalysts based on aminopyridine ligands have been shown highly active in the light-driven reduction of ketones and aldehydes to alcohols, using water as the source of hydrogen atom.

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