A5086372340- Polyoxometalates: Synthesis and Applications
- Metal-Organic Frameworks: Synthesis and Applications
- Carbon dioxide utilization in catalysis
- Crystallization and Solubility Studies
- CO2 Reduction Techniques and Catalysts
- X-ray Diffraction in Crystallography
- Advanced Photocatalysis Techniques
- Catalysis and Oxidation Reactions
- Organometallic Complex Synthesis and Catalysis
- Advanced Nanomaterials in Catalysis
- Vanadium and Halogenation Chemistry
- Chemical Synthesis and Characterization
- Crystallography and molecular interactions
- Catalytic Processes in Materials Science
- Chemical Synthesis and Reactions
- Nanocluster Synthesis and Applications
- Electrocatalysts for Energy Conversion
- Asymmetric Hydrogenation and Catalysis
- Supramolecular Self-Assembly in Materials
- Ammonia Synthesis and Nitrogen Reduction
- Inorganic Chemistry and Materials
- Lanthanide and Transition Metal Complexes
- Ionic liquids properties and applications
- Organoboron and organosilicon chemistry
- Dendrimers and Hyperbranched Polymers
Institut Català d'Investigació Química
2024-2025
Universitat Rovira i Virgili
2016-2024
Sorbonne Université
2021-2024
Centre National de la Recherche Scientifique
2021-2023
Université Paris Sciences et Lettres
2021-2023
Laboratoire de chimie des processus biologiques
2021-2023
Collège de France
2021-2023
Observatori de l'Ebre
2017-2018
Aqueous solutions of polyoxometalates (POMs) have been shown to potential as high-capacity energy storage materials due their for multi-electron redox processes, yet the mechanism reduction and practical limits are currently unknown. Herein, we explore processes that allow highly reduced POM clusters form {MO3}y absorb y electrons in aqueous solution, focusing mechanistically on Wells-Dawson structure X6[P2W18O62], which comprises 18 metal centers can uptake up reversibly (y = 18) per...
The immobilization of polyoxometalates (POMs) near catalytic centers metal–organic frameworks (MOFs) has been reported as an advantageous strategy to boost their photocatalytic activity toward strategic reactions such CO2 reduction (CO2RR) or hydrogen evolution (HER), although the reasons for enhancement are still poorly understood. Unveiling role POM guests in reaction mechanisms is therefore a key step development next generation multicomponent materials with optimal performances. Here, we...
Molecularly defined organometallic rhodium phosphine complexes were efficiently heterogenized within a MOF structure without affecting neither their molecular nature nor catalytic behavior. Phosphine-functionalized MOF-808 served as solid ligand in series of eight catalysts. These MOF-heterogenized catalysts showed activity up to 2100 h–1 for ethylene hydroformylation toward propionaldehyde the sole carbon-containing product. The combined experimental and computational methods applied this...
We report the use of Zr-based metal–organic frameworks (MOFs) MOF-545 and MOF-545(Cu) as supports to prepare catalysts with uniformly highly dispersed Ni nanoparticles (NPs) for CO2 hydrogenation into CH4. In first step, we studied MOF support under catalytic conditions using operando diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy, ex situ characterizations (PXRD, XPS, TEM, EDX-element mapping), DFT calculations. showed that high-temperature undoubtedly confer a...
Nb-monosubstituted Lindqvist-type polyoxometalates (POM), (Bu4N)4[(NbW5O18)2O] (1) and (Bu4N)3[Nb(O)W5O18] (2), catalyze epoxidation of alkenes with hydrogen peroxide mimic the catalytic performance heterogeneous Nb-silicate catalysts. Dimer 1 is more active than monomer 2, but activity latter increases in presence acid. Kinetic spectroscopic studies suggest a mechanism that involves generation (Bu4N)2[Nb(OH)W5O18] (3), interaction 3 H2O2 leading to protonated peroxo niobium species,...
The epoxidation of allylic alcohols with H2O2 catalyzed by the hybrid [α-B-SbW9O33(tBuSiO)3Ti(OiPr)]3– (1) anion as a molecular model heterogeneous Ti-silicalite TS-1 catalyst was analyzed means DFT to determine main factors that control catalytic process and, finally, improve value available catalysts. Our calculations revealed unlike other alkenes, can bind Ti center after activation precatalyst via hydrolysis give corresponding Ti-alcoholate, which is resting state. Next, dissociative...
Three crystalline heterometallic molybdenum(V) phosphates have been synthesized under hydrothermal conditions. They all contain {M[P4Mo6O28(OH)3]2}16– [M = Mn(II) or Co(II)] polyoxometalate (POM) units, with the M ions sandwiched between two {P4MoV6} rings. In presence of Fe(II) in reaction medium, a three-dimensional (3D) Fe–Mn compound built from connection Mn(P4Mo6)2 units to and Fe(III) centers by extra phosphate is obtained. Alternatively, introduction [Ru(bpy)3]2+ complexes synthetic...
A complete picture of the reaction mechanism driving photocatalytic reduction CO 2 into formate promoted by Zr-based porphyrinic MOF-545 in CH 3 CN/TEOA solutions is provided for first time combining experimental and computational approaches.
The decomposition of hydrogen peroxide (H2O2) is the main undesired side reaction in catalytic oxidation processes industrial interest that make use H2O2 as a terminal oxidant, such epoxidation alkenes. However, mechanism responsible for this still poorly understood, thus hindering development design rules to maximize efficiency oxidations terms product selectivity and oxidant utilization efficiency. Here, we thoroughly investigated using Zr-monosubstituted dimeric Lindqvist tungstate,...
The present paper reports a remote carbon-to-carbon boryl migration via an intramolecular 1,4-B/Cu shift, which establishes in situ stereospecific electrophilic trap on the alkene moiety. synthetic application is developed to prepare functionalized cyclopentenes by means of palladium-catalyzed regioselective coupling that completes strategic cyclopropanation and generates valuable structural bicyclic systems. mechanism characterized DFT (density functional theory) calculations showed...
The molecular interactions between the CeIV -substituted Keggin anion [PW11 O39 Ce(OH2 )4 ]3- (CeK) and hen egg-white lysozyme (HEWL) were investigated by dynamics simulations. analysis of CeK was compared with dimer [(PW11 )2 Ce]10- (CeK2 ) ZrIV Lindqvist [W5 O18 Zr(OH2 )(OH)]3- (ZrL) to understand how POM features such as shape, size, charge, or type incorporated metal ion influence POM⋅⋅⋅protein interactions. Simulations revealed two regions protein in which interacts strongly: cationic...
Ti- and Nb-monosubstituted tungstates of the Lindqvist structure, (Bu4N)3[(CH3O)TiW5O18] (TiW5) (Bu4N)2[(CH3O)NbW5O18] (NbW5), display catalytic reactivity analogous to that heterogeneous Nb-containing catalysts in alkene oxidation with aqueous hydrogen peroxide. In this work, we make an attempt rationalize differences observed performance Ti Nb single-site for epoxidation H2O2 using MW5 (M = Nb) as tractable molecular models. cyclohexene, NbW5 reveals higher activity heterolytic pathway...
The influence of the composition chaotropic polyoxometalate (POM) anions on their affinity to biological systems was studied by means atomistic molecular dynamics (MD) simulations. variations in hen egg-white lysozyme (HEWL) were analyzed along two series POMs whereby charge or size and shape metal cluster are modified systematically. Our simulations revealed a quadratic relationship between POM its HEWL as consequence parabolic growth POM⋅⋅⋅water interaction with charge. As increases,...
Zr-monosubstituted Lindqvist-type polyoxometalates (Zr-POMs), (Bu4N)2[W5O18Zr(H2O)3] (1) and (Bu4N)6[{W5O18Zr(μ-OH)}2] (2), have been employed as molecular models to unravel the mechanism of hydrogen peroxide activation over Zr(IV) sites. Compounds 1 2 are hydrolytically stable catalyze epoxidation C═C bonds in unfunctionalized alkenes α,β-unsaturated ketones, well sulfoxidation thioethers. Monomer is more active than dimer 2. Acid additives greatly accelerate oxygenation reactions increase...
Catalytic stability and overall performance enhancement for the methane dehydroaromatization process using a combination of hexamolybdate species as Mo precursors MCM-22 catalysts support.
The electrification of ammonia synthesis is a key target for its decentralization and lowering impact on atmospheric CO2 concentrations. lithium metal electrochemical reduction nitrogen to using alcohols as proton/electron donors an important advance, but requires rather negative potentials, anhydrous conditions. Organometallic electrocatalysts redox mediators have also been reported. Water proton electron donor has not demonstrated in these reactions. Here N2 NH3 electrocatalytic inorganic...
Here we report on the use of a silanol-decorated polyoxotungstate, [SbW9O33(tBuSiOH)3]3– (1), as molecular support to describe coordination vanadium atom at single-site silica surfaces. By reacting [V(Mes)3·thf] (Mes = 2,4,6-trimethylphenyl) with 1 in tetrahydrofuran, vanadium(III) derivative [SbW9O33(tBuSiO)3V(thf)]3– (2) was obtained. Compound 2 displays paramagnetic behavior expected for d2-VIII high spin complex (SQUID measurements) triplet electronic ground state (ca. 30 kcal·mol–1 more...
Polyoxometalate-amino acid hybrids (<bold>POM-F</bold>and<bold>POM-FF</bold>) self-assemble into spherical architectures with high reproducibility in several “good–bad” solvent mixtures.
Electrocatalytic CO
The understanding of the molecular state vanadium-oxo clusters (polyoxovanadates, POVs) in solution and on surface is a key to their target application catalysis as well electronics spintronics. We here report results combined experimental computational study behavior nucleophilic polyoxoanions [VIV10VV8O42(I)]5– charged balanced by Et4N+ water, one-phase organic N,N-dimethylformamid (DMF) or acetonitrile (MeCN), mixed MeCN–water, at hybrid liquid–surface interface. characteristics compound...
Light-dependent reduction of carbon dioxide (CO2) can be developed using nonexpensive and abundant molecular catalysts inorganic photosensitizers based on nonnoble metals. The photoreduction CO2 catalyzed by a series 11 metal-salophen complexes, variously functionalized salophen ligands, has been investigated Cu-based photosensitizer, [CuI(bathocupoine)(xantphos)], for light harvesting. This provides one the currently few fully earth-abundant systems efficient driven visible light. Using...
A series of stable reduction–oxidation states the cagelike [I@VIVxVV18–xO42]5–x polyoxovanadate (POV) with x = 8, 10, 12, 16, and 18 were studied density functional theory molecular dynamics to gain insight into structural electron distribution characteristics these metal–oxo clusters analyze charge/redox-dependent assemblage processes in water acetonitrile (MeCN) solutions. The calculations show that interplay between POV redox state (molecular charge) solvent polarity, countercation size,...