Les ordres de charges et d\u2019orbitales comme moteur de la supraconductivit\u00e9 dans les oxydes complexes<\/strong><\/h2>\n\n\n\nLa supraconductivit\u00e9, caract\u00e9ris\u00e9e par une r\u00e9sistance \u00e9lectrique nulle et l\u2019expulsion du champ magn\u00e9tique, reste limit\u00e9e par des temp\u00e9ratures critiques Tc relativement modestes, atteignant au mieux 135 K dans les cuprates \u00e0 pression ambiante. Dans les oxydes complexes, comprendre les m\u00e9canismes permettant d\u2019augmenter Tc constitue un enjeu majeur, en particulier du point de vue de la chimie \u00e9lectronique et structurale.<\/p>\n\n\n\n
Les oxydes d\u00e9riv\u00e9s des phases de type Ruddlesden-Popper An+1BnO3n+1 jouent un r\u00f4le central dans cette probl\u00e9matique. Dans ces syst\u00e8mes, la supraconductivit\u00e9 appara\u00eet fr\u00e9quemment \u00e0 proximit\u00e9 d\u2019une transition entre une phase isolante et une phase m\u00e9tallique. Cette transition est souvent associ\u00e9e \u00e0 la disparition d\u2019ordres \u00e9lectroniques tels que les ordres de charges (dismutation cationique) ou d\u2019orbitales, fr\u00e9quemment li\u00e9s \u00e0 des instabilit\u00e9s structurales de type Jahn-Teller.<\/p>\n\n\n\n
Dans ce s\u00e9minaire, je montre, \u00e0 partir de simulations de premiers principes bas\u00e9es sur la th\u00e9orie de la fonctionnelle de la densit\u00e9 (DFT), que la supraconductivit\u00e9 \u00e9merge syst\u00e9matiquement \u00e0 proximit\u00e9 de ces phases ordonn\u00e9es. M\u00eame si ces ordres disparaissent dans la phase m\u00e9tallique, leurs fluctuations persistent et g\u00e9n\u00e8rent un couplage \u00e9lectron-phonon suffisant pour initier la supraconductivit\u00e9.<\/p>\n\n\n\n
Ces r\u00e9sultats sugg\u00e8rent ainsi que les phases isolantes ordonn\u00e9es et supraconductrices partagent une origine commune1,2<\/sup>. Enfin, je mets en \u00e9vidence que les distorsions structurales des r\u00e9seaux d\u2019octa\u00e8dres O\u2086, comme les rotations, permettent de moduler ce couplage \u00e9lectron-phonon. Ceci ouvre la voie \u00e0 une strat\u00e9gie d\u2019ing\u00e9nierie structurale des oxydes pour optimiser Tc.<\/p>\n\n\n\n1. J. Varignon, M. Bibes, and A. Zunger, Nat. Comm. 10, 1658 (2019)<\/p>\n\n\n\n
2. A. A. Carrasco-Alvarez, S. Petit, W. Prellier, M. Bibes, and J. Varignon, Nat. Comm. 16, 1458 (2025)<\/p>\n\n\n\n
\n
\n
\n
Yann Le Godec<\/strong><\/strong><\/strong><\/strong><\/strong><\/h2>\n\n\n\nInstitut de Min\u00e9ralogie, de Physique des Mat\u00e9riaux et de Cosmochimie (IMPMC)<\/p>\n\n\n\n
Jeudi 12 mars 2026<\/p>\n<\/div>\n<\/div>\n\n\n\n
Synth\u00e8se sous conditions extr\u00eames de nouveaux mat\u00e9riaux l\u00e9gers aux propri\u00e9t\u00e9s remarquables<\/strong><\/h2>\n\n\n\nLa chimie moderne sous hautes pressions constitue aujourd\u2019hui un vaste et dynamique champ de recherche, offrant des perspectives prometteuses pour le d\u00e9veloppement de nouveaux mat\u00e9riaux d\u2019int\u00e9r\u00eat industriel. Bien que cette discipline reste relativement jeune compar\u00e9e \u00e0 la chimie conventionnelle, elle r\u00e9v\u00e8le d\u00e9j\u00e0 un potentiel exceptionnel, encore largement inexplor\u00e9. Son caract\u00e8re pionnier et ses perspectives r\u00e9volutionnaires en font une v\u00e9ritable terra incognita scientifique, justifiant ainsi l\u2019engouement croissant qu\u2019elle suscite.<\/p>\n\n\n\n
Dans ce contexte, les avanc\u00e9es r\u00e9centes en diffraction des rayons X sous conditions extr\u00eames ont boulevers\u00e9 les m\u00e9thodes d\u2019exploration de ces nouveaux territoires, ouvrant la voie \u00e0 des d\u00e9couvertes sans pr\u00e9c\u00e9dent. Au cours de la derni\u00e8re d\u00e9cennie, l\u2019utilisation intensive du rayonnement synchrotron in situ a permis l\u2019observation directe des voies de synth\u00e8se de nouveaux mat\u00e9riaux, qu\u2019ils soient stables ou m\u00e9tastables, sous conditions extr\u00eames. Ces mat\u00e9riaux, souvent inaccessibles par les m\u00e9thodes conventionnelles, pr\u00e9sentent des propri\u00e9t\u00e9s remarquables, telles que la supraconductivit\u00e9 \u00e0 haute temp\u00e9rature, une duret\u00e9 exceptionnelle ou encore un photovolta\u00efsme optimis\u00e9.<\/p>\n\n\n\n
L\u2019observation in situ des processus de synth\u00e8se autorise aujourd\u2019hui une d\u00e9termination beaucoup plus pr\u00e9cise des conditions thermodynamiques n\u00e9cessaires \u00e0 l\u2019acc\u00e8s aux \u00e9tats m\u00e9tastables. Dans cette pr\u00e9sentation, je montrerai que la combinaison de tr\u00e8s hautes pressions et temp\u00e9ratures avec des sondes in situ par diffraction des rayons X utilisant le rayonnement synchrotron constitue une cl\u00e9 m\u00e9thodologique essentielle pour contr\u00f4ler la composition et la microstructure (nanostructuration) de nouveaux mat\u00e9riaux (borures, carbures, compos\u00e9s du silicium, etc.) pr\u00e9sentant des propri\u00e9t\u00e9s exceptionnelles.<\/p>\n\n\n\n
\n
\n
\n
Camila Dalben<\/strong><\/strong><\/strong><\/strong><\/strong><\/strong><\/h2>\n\n\n\nIMEC, Leuven, Belgium<\/p>\n\n\n\n
Jeudi 12 f\u00e9vrier 2026<\/p>\n\n\n\n
Joint webinar Division de Chimie du Solide \u2013 SCF \/ Division of Solid State and Materials Chemistry \u2013 EuChemS<\/strong><\/p>\n<\/div>\n<\/div>\n\n\n\nExploiting the electric response of materials for improved analytical performance<\/strong><\/h2>\n\n\n\nWe introduce a new method for solid-phase reversible immobilization of biomolecules based on internal, electric control of surface charge of the solid phase. Unlike traditional solid-phase extraction (SPE) approaches, that use solvent composition to select for affinity and often require multiple solvent changes and time-consuming protocols, our system leverage materials whose surface charge and electric double layer can be dynamically adjusted by applying an external voltage. This allows direct, online control of biomolecule adsorption and desorption rates. Furthermore, our results show that other properties of the material, beyond surface charge can be manipulated to obtain significant gains in the selectivity and yield of the reaction. We will discuss how the degree of cross-linking and the specific functional groups present on the surface significantly enhance the selectivity and yield of the extraction process. This electrically driven strategy enables rapid, selective, and high-yield biomolecule separation without the need for complex solvent gradients, allowing more streamlined and effective workflows in bioanalytical and preparative applications.<\/p>\n\n\n\n
\n
\n
\n
Vincent Maisonneuve<\/strong><\/strong><\/strong><\/strong><\/strong><\/strong><\/strong><\/h2>\n\n\n\nInstitut des Mol\u00e9cules et Mat\u00e9riaux du Mans (IMMM)<\/p>\n\n\n\n
Jeudi 15 janvier 2026<\/p>\n<\/div>\n<\/div>\n\n\n\n
Apport des mat\u00e9riaux fluor\u00e9s inorganiques : de la synth\u00e8se aux applications<\/strong><\/h2>\n\n\n\nAu fil des ann\u00e9es, les mat\u00e9riaux fluor\u00e9s se sont impos\u00e9s au c\u0153ur de nombreuses applications. De par ses propri\u00e9t\u00e9s singuli\u00e8res, le fluor conf\u00e8re aux solides des fonctionnalit\u00e9s sp\u00e9cifiques qui leur valent une place strat\u00e9gique dans de multiples domaines allant de l\u2019optique \u00e0 l\u2019\u00e9nergie (nucl\u00e9aire, batteries, \u2026), en passant par la catalyse ou la m\u00e9dicine. Son introduction dans les mat\u00e9riaux inorganiques constitue un levier essentiel pour moduler les propri\u00e9t\u00e9s \u00e9lectroniques, optiques, magn\u00e9tiques ou \u00e9lectrochimiques.<\/p>\n\n\n\n
Cette pr\u00e9sentation montrera comment les choix de composition, de structure, de m\u00e9thode de pr\u00e9paration jusqu\u2019\u00e0 l\u2019\u00e9chelle nanocristalline permettent d\u2019ajuster des propri\u00e9t\u00e9s cibl\u00e9es et d\u2019ouvrir des perspectives applicatives. Mon propos sera illustr\u00e9 par des exemples issus des \u00e9tudes r\u00e9centes r\u00e9alis\u00e9es \u00e0 l\u2019IMMM, afin de d\u00e9montrer qu\u2019au-del\u00e0 des r\u00e9sultats obtenus, le fluor restera probablement l\u2019un des acteurs cl\u00e9s des mat\u00e9riaux du futur, en particulier au service de la transition \u00e9nerg\u00e9tique et des technologies \u00e9mergentes n\u00e9cessaires pour atteindre la neutralit\u00e9 carbone.<\/p>\n<\/div>\n<\/div>\n\n\n\n
\n
2025<\/span>+<\/span><\/button><\/h3>\n\n\n\n\n
\n
\n
\n
Thomas Devic<\/strong><\/strong><\/h2>\n\n\n\nInstitut des Mat\u00e9riaux de Nantes Jean Rouxel<\/p>\n\n\n\n
Jeudi 11 d\u00e9cembre 2025<\/p>\n<\/div>\n<\/div>\n\n\n\n
Polym\u00e8res de coordination poreux (Metal Organic Frameworks, MOFs) : pourquoi se tourner vers des fonctions complexantes alternatives aux carboxylates ?<\/strong><\/h2>\n\n\n\nLes polym\u00e8res de coordination poreux cristallis\u00e9s, ou Metal Organic Frameworks (MOFs), sont construits \u00e0 partir de d\u2019oxoclusters inorganiques connect\u00e9s entre eux par des ligands organiques polytopiques pour d\u00e9finir des pores de tailles et formes vari\u00e9es. Bien que le domaine soit largement domin\u00e9 par les ligands carboxylates (par exemple mat\u00e9riaux HKUST-1, MIL-100, UiO-66) et azolates (ZIF-8, CALF-20), l\u2019utilisation de fonctions complexantes alternatives est un moyen d\u2019\u00e9largir la gamme de composition et de propri\u00e9t\u00e9s accessibles. Nous nous int\u00e9ressons en particulier aux ligands poly-ph\u00e9nolates (cat\u00e9cholate, gallate), \u00e9ventuellement bio-sourc\u00e9s, et leurs analogues soufr\u00e9s.<\/p>\n\n\n\n
Nous discuterons tout d\u2019abord comment les caract\u00e9ristiques physico-chimiques de ces familles de ligands (charge, pKa, caract\u00e8re dur\/mou) affecte \u00e0 la foi la synth\u00e8se et la cristallochimie des MOFs d\u00e9riv\u00e9s, puis pr\u00e9senterons les relations entre composition, structure et propri\u00e9t\u00e9s de ces MOFs, notamment \u00e9lectrochimiques,[1] d\u2019adsorption de gaz,[2] ou encore de r\u00e9activit\u00e9 chimique.[3]<\/p>\n\n\n\n
[1] N. Gedikoglu et al., J. Mater. Chem. A<\/em> 2023<\/strong>, 11, 23909; S. De et al., J. Mater. Chem. A<\/em> 2023<\/strong>, 11, 25465; L.H.B. Nguyen et al., Chem. Commun.<\/em> 2025<\/strong>, 61, 9614.<\/p>\n\n\n\n[2] L. Cooper et al. Chem. Commun.<\/em> 2015<\/strong>, 51, 5848; N. Heymans et al. J. Phys. Chem C.<\/em> 2020<\/strong>, 124, 3188; N. Gedikoglu et al., Micro. Meso. Mater.<\/em> 2024<\/strong>, 367, 112968.<\/p>\n\n\n\n[3] G. Mouchaham et al., Chem. Commun.<\/em> 2017<\/strong>, 53, 7661; S. De et al. Inorg. Chem.<\/em> 2020<\/strong>, 59, 10129.<\/p>\n\n\n\n\n
\n
\n
Otto Mustonen<\/strong><\/strong><\/strong><\/h2>\n\n\n\nDepartment of Chemistry and Materials Science, Aalto University<\/p>\n\n\n\n
Jeudi 13 novembre 2025<\/p>\n\n\n\n
Joint webinar Division de Chimie du Solide \u2013 SCF \/ Division of Solid State and Materials Chemistry \u2013 EuChemS<\/strong><\/p>\n<\/div>\n<\/div>\n\n\n\nTuning quantum magnetism in double perovskites using non-magnetic cations<\/strong><\/h2>\n\n\n\nQuantum materials have magnetic or electronic properties arising from a non-trivial quantum mechanic origin and potential applications from energy to quantum computing [1]. Similarly, quantum magnets are magnetic materials with strong quantum effects and often unusual or exotic ground states. These typically arise in materials with low-dimensional interactions and low (\u201cquantum\u201d) spin on the magnetic cation such as S = 1\/2 Cu2+<\/sup> and V4+<\/sup> or S = 1 Ni2+<\/sup>.<\/p>\n\n\n\nIn this talk, I will show how non-magnetic d10 and d0 cation be used to tune magnetic interactions and ground states in double perovskites and related structures [2]. This is especially useful in quantum magnets, where new and exotic ground states can arise. The most exciting example of this is the Cu2+<\/sup> double perovskite Sr2<\/sub>CuTe1-x<\/sub>Wx<\/sub>O6<\/sub>, where magnetic ordering is fully suppressed in a large composition range [3]. This represents the first observation of a spin-liquid-like state in a square-lattice antiferromagnet.<\/p>\n\n\n\n[1] R. Cava, N. de Leon, and W. Xie, Chem. Rev.<\/em> 121<\/strong>, 2777 (2021).<\/p>\n\n\n\n[2] O. Mustonen et al., Chem. Mater.<\/em> 32, 7070 (2020).<\/p>\n\n\n\n[3] O. Mustonen et al., Chem. Mater. 36<\/strong>, 501 (2024).<\/p>\n\n\n\n\n
\n
\n
Ania Conchi<\/strong><\/strong><\/strong><\/strong><\/h2>\n\n\n\nConditions Extr\u00eames et Mat\u00e9riaux : Haute Temp\u00e9rature et Irradiation (CEMHTI), Orl\u00e9ans<\/p>\n\n\n\n
Jeudi 9 octobre 2025<\/p>\n<\/div>\n<\/div>\n\n\n\n
Photo(electro)catalysis based on carbon materials: novel directions in energy conversion and environmental remediation<\/strong><\/h2>\n\n\n\nMetal-based catalysis is ruling the world\u2019s most important industrial processes in the fields of energy conversion\/storage and environmental protection (e.g., fuel cells, batteries, supercapacitors, water splitting, carbon dioxide conversion into fuels, nitrogen fixation). However, it faces multiple disadvantages related to the high cost of precious metals (very often most active ones), the uneven geographical distribution of their reserves, and the limited durability due to poisoning during operation. Replacing metallic catalysts with noble metal-free abundant materials has become a priority of most research programs to boost sustainable and renewable solutions towards current energetic and environmental challenges. The use of materials as alternatives to metallic catalysts in photo- and electrocatalytic applications has become an active research area, with many different forms of carbon having shown high catalytic activity and better performance and durability than some state-of-the-art non-precious metal catalysts for energy conversion\/storage and environmental protection.<\/p>\n\n\n\n
In photocatalysis, the efficient and selective conversion of solar light is the key to redress the balance of energy derived from fossil fuels, with most research efforts in non-biological applications such as synthetic chemistry, cleaning surfaces, solar to electricity, fuels and valuable chemicals or environmental remediation. While heterogeneous photocatalysis has been mainly associated to metal-based semiconductors, recent evidences have shown the performance of metal-free carbon materials in this area, owing to their capacity to stabilize photogenerated charge carriers through charge transfer reactions in nanopores and defective sites, enabling molecular transformations of interest. The challenge is yet the switching photocurrent control in carbon materials at the molecular level, which would open new possibilities for the design of photovoltaic and optoelectronic devices.<\/p>\n\n\n\n
At the same time, carbon materials are efficient electrocatalysts owing to the combination of an adequate architecture of interconnected pore channels to boost electrode-probe interactions, and a balanced composition with surface functional groups capable of activating the probe molecules, while preserving wettability and\/or electrical conductivity. Unravelling the practical feasibility of carbon-based electrocatalysts in strategic electrochemical reactions must aim to discriminate the roles of porosity and surface chemistry, enhance conversions efficiencies, and selectivity.<\/p>\n\n\n\n
The purpose of this communication is to perform a rational analysis of the photo-electrocatalytic activity of carbons, providing a comprehensive interpretation of the origin, reactivity and stabilization pathways of the charge carriers. The perspectives of utilization in various applications will be discussed, with examples of performance in advanced oxidation processes for the degradation of pollutants, photonic conversion layers to improve the performance of solar cells, or the conversion of strategic energetic vectors (reduction of CO2, fixation of N-compounds, hydrogen peroxide).<\/p>\n\n\n\n
\n
\n
\n
Ovidiu Ersen<\/strong><\/strong><\/strong><\/strong><\/strong><\/h2>\n\n\n\nInstitut de Physique et Chimie des Mat\u00e9riaux de Strasbourg (IPCMS)<\/p>\n\n\n\n
Jeudi 11 septembre 2025<\/p>\n<\/div>\n<\/div>\n\n\n\n
Microscopie \u00e9lectronique in situ pour l\u2019\u00e9tude de la formation et de l\u2019\u00e9volution des nanomat\u00e9riaux<\/strong><\/h2>\n\n\n\nL\u2019\u00e9tude \u00e0 haute r\u00e9solution spatiale des propri\u00e9t\u00e9s et de l\u2019\u00e9volution des nanomat\u00e9riaux dans des environnements repr\u00e9sentatifs de leur formation ou usage dans des applications est indispensable pour comprendre les processus physiques et chimiques qui gouvernent leurs propri\u00e9t\u00e9s d\u2019int\u00e9r\u00eat. Dans ce contexte, gr\u00e2ce \u00e0 ses multiples atouts, la microscopie \u00e9lectronique en transmission in situ, en combinaison avec d\u2019autres techniques compl\u00e9mentaires, est particuli\u00e8rement adapt\u00e9e pour le suivi en temps r\u00e9el de la croissance des nanomat\u00e9riaux, de leurs transformations structurales en fonction de la contrainte appliqu\u00e9e ou de leur \u00e9volution dans des conditions \u00ab operando \u00bb. Les domaines concern\u00e9s sont nombreux, la synth\u00e8se des mat\u00e9riaux par voie chimique [1], la catalyse h\u00e9t\u00e9rog\u00e8ne [2], l\u2019\u00e9lectrochimie [3], les processus de biomin\u00e9ralisation [4] etc., et plus g\u00e9n\u00e9ralement tous les processus qui impliquent des r\u00e9actions \u00e0 l\u2019interface \u00ab gaz-solide \u00bb ou \u00ab liquide-solide \u00bb. Les nouveaux d\u00e9veloppements en microscopie \u00e9lectronique, concernant l\u2019instrumentation ou les m\u00e9thodologies \u00e0 utiliser, sont tout aussi nombreux et ouvrent des nouvelles perspectives pour l\u2019\u00e9tude \u00e0 hautes r\u00e9solutions spatiale et temporelle de l\u2019ensemble des syst\u00e8mes d\u2019int\u00e9r\u00eat, y compris ceux qui sont sensibles \u00e0 l\u2019irradiation \u00e9lectronique.<\/p>\n\n\n\n
[1] C. Sidhoum, D. Constantin, D. Ihiawakrim, M. Lenertz, T. Bizien, C. Sanchez, O. Ersen, Chem Mater<\/strong> 35 (19), p. 7943 (2023<\/strong>).<\/p>\n\n\n\n[2] S. Sharna, M. Bahri, C. Bouillet, V. Rouchon, A. Lambert, A.-S. Gay, D. Chiche, O. Ersen, Nanoscale<\/strong> 13, p. 9747 (2021<\/strong>).<\/p>\n\n\n\n[3] N. Ortiz-Pena, D. Ihiawakrim, M. Han, B. Lassalle-Kaiser, S. Carenco, C. Sanchez, C. Laberty-Robert, D. Portehault, O. Ersen, ACS Nano<\/strong> 13, 10, p. 11372 (2019<\/strong>).<\/p>\n\n\n\n[4] V. Ramnarain, T. Georges, N. Ortiz Pe\u00f1a, D. Ihiawakrim, M. Longuinho, H. Bulou, C. Gervais, C. Sanchez, T. Aza\u00efs, O. Ersen, JACS<\/strong> 44, p. 15236 (2022<\/strong>).<\/p>\n\n\n\n\n
\n
\n
Ladislav Kavan<\/strong><\/strong><\/strong><\/strong><\/strong><\/strong><\/h2>\n\n\n\nJ. Heyrovsky Institute of Physical Chemistry, Prague, CZ<\/p>\n\n\n\n
Jeudi 12 juin 2025<\/p>\n\n\n\n
Joint webinar Division de Chimie du Solide \u2013 SCF \/ Division of Solid State and Materials Chemistry \u2013 EuChemS<\/strong><\/p>\n<\/div>\n<\/div>\n\n\n\nPhotoelectrochemistry of TiO2, SnO2, ZnO: Fundamentals, Pitfalls, Applications<\/strong><\/h2>\n\n\n\nMaterials based on TiO2, SnO2 and ZnO triggered the rise of semiconductor photoelec-trochemistry in the last century, with pivotal advances in photocatalysis, photovoltaics, and solar fuel generation from, e.g., H2O. N2, CO2. These three materials are currently producing ca. 130 scientific publications daily! This deluge of information causes, how-ever, conflicting interpretations, oversimplifications, and misconceptions, too [1]. Exam-ples are: (i) Determination of flatband potentials and donor concentrations by Mott-Schottky analysis, e.g., for nanotextured materials; (ii) Calculation of work functions and band edges by DFT ignoring the effects of crystal environment and\/or imperfections; (iii) Measurement of work functions and band edges by photoelectron spectroscopy (XPS\/UPS\/NAP) and Kelvin probe; (iv) Application of the classical G\u00e4rtner-Butler model for carrier dynamics in semiconductor photoanodes, discounting the gradient of electro-chemical potentials for the e-\/h+ separation; (v) The \u201csuperhydrophilicity\u201d in UV-irradiated titania is caused by selective adsorption\/photodegradation of airborne carbox-ylic acids, rather than by structural modifications of the TiO2 surface.<\/p>\n\n\n\n
[1] L. Kavan, Electrochemistry and band structure of semiconductors (TiO\u00ac2, SnO2, ZnO): Avoiding pitfalls and textbook errors, J. Solid State Electrochem. 28 (2024) 829-845.<\/p>\n\n\n\n
\n
\n
\n
Marco Faustini<\/strong><\/strong><\/strong><\/strong><\/strong><\/strong><\/strong><\/h2>\n\n\n\nLaboratoire de Chimie de la Mati\u00e8re Condens\u00e9e de Paris<\/p>\n\n\n\n
Jeudi 10 avril 2025<\/p>\n<\/div>\n<\/div>\n\n\n\n
From Nanostructured Oxides to Porous High Entropy Alloys: Bridging Sol-Gel Processing and Metallurgy<\/strong><\/h2>\n\n\n\nThe sol-gel process is traditionally used to shape oxides; it offers a versatile and well-established route to synthesize nanostructured materials from solutions with controlled composition, porosity, and morphology. Our research aims to push the boundaries of sol-gel processing beyond oxides, extending its applicability to the shaping of metallic materials, which presents additional challenges related to reduction processes, phase control, and structural integrity. To introduce this chemistry, we will start by discussing the case of noble metal oxides, particularly porous Ir-based and mixed oxides, which are key materials for the oxygen evolution reaction in proton exchange membrane water electrolyzers. In particular, we unveil that the spontaneous formation of hollow structures can be achieved thanks to the pseudo-Kirkendall process on metallic salts. Building on this foundation, we then tackle the more complex and challenging case of metallic high entropy alloys (HEAs), a class of materials composed of five or more homogeneously mixed elements in nearly equimolar ratios. HEAs have rapidly gained importance in the field of catalysis and electrocatalysis, due to their high chemical and thermal stability and to the virtually unlimited types of active sites accessible, stemming from the high configurational entropy. [1] However, fabrication of these materials usually requires harsh conditions. By using the brute force of spray-drying, we developed a low temperature sol-gel approach to shape HEA nanoparticles into macro- and mesoporous architectures. [2] Porous, fully reduced HEA-based particles are obtained by annealing the hybrid particles at temperatures as low as 350\u00b0C under inert atmosphere by carbothermal treatment showed a good catalytic activity towards the CO oxidation reaction and stability up to 800\u00b0C. A multi-technique in situ analysis was performed to understand the solid-state carboreduction process at the hybrid organic\/inorganic interface and the atomic mixing. Moreover, we extended the sol-gel approach to shape metallic material as films and patterns by combining this chemistry with Nanoimprint Lithography or Deep X-Ray Lithography [3,4]. In conclusion, this work shows a versatile approach for the exploration of architectured metallic materials with important implications in optics, catalysis and electrocatalysis.<\/p>\n\n\n\n
[1] Y. Xin, S. Li, Y. Qian, W. Zhu, H. Yuan, P. Jiang, R. Guo, L. Wang, ACS Catal. 10, 11280\u221211306 (2020).<\/p>\n\n\n\n
[2] M. L. De Marco, W. Baaziz, S. Sharna, F. Devred, C. Poleunis, A. Chevillot-Biraud, S. Nowak, R. Haddad, M. Odziomek, C. Boissiere, \u0300D. P. Debecker, O. Ersen, J. Peron, M. Faustini, ACS Nano, 16, 15837-15849 (2022)<\/p>\n\n\n\n
[3] M. Gayrard; J. Voronkoff; C. Boissi\u00e8re; D. Montero; L. Rozes; A. Cattoni; J. Peron; M. Faustini , Nano Letters, 21, 5, 2310-2317, (2021)<\/p>\n\n\n\n
[4] M. Gayrard; F. Chancerel; M. L. De Marco, D. Naumenko, C. Boissi\u00e8re; L. Rozes; H. Amenitsch; J. Peron; A. Cattoni; M. Faustini, Small, 18, 2104204, (2022)<\/p>\n\n\n\n
\n
\n
\n
Vanessa Fiero<\/strong><\/strong><\/strong><\/strong><\/strong><\/strong><\/strong><\/strong><\/h2>\n\n\n\nInstitut Jean Lamour, Epinal<\/p>\n\n\n\n
Jeudi 13 mars 2025<\/p>\n<\/div>\n<\/div>\n\n\n\n
Les mat\u00e9riaux carbon\u00e9s biosourc\u00e9s au c\u0153ur de la transition \u00e9nerg\u00e9tique<\/strong><\/h2>\n\n\n\nLes tanins sont des mol\u00e9cules polyph\u00e9noliques utilis\u00e9es notamment pour le traitement du cuir. La plupart des tanins sont disponibles commercialement avec une qualit\u00e9 constante, ce qui en fait des pr\u00e9curseurs comp\u00e9titifs face aux mol\u00e9cules ph\u00e9noliques synth\u00e9tiques et potentiellement dangereuses. \u00c0 l\u2019\u00e9quipe Mat\u00e9riaux biosourc\u00e9s de l\u2019Institut Jean Lamour, nous utilisons les tanins comme pr\u00e9curseurs pour divers mat\u00e9riaux carbon\u00e9s aux structures, textures et applications vari\u00e9es. Ils pr\u00e9sentent plusieurs avantages : ils sont naturels, renouvelables, non toxiques, r\u00e9actifs, \u00e9conomiques et solubles dans l\u2019eau ainsi que dans les solvants protiques.<\/p>\n\n\n\n
Des carbones m\u00e9soporeux, ordonn\u00e9s ou d\u00e9sordonn\u00e9s, peuvent \u00eatre obtenus par auto-assemblage via m\u00e9canosynth\u00e8se du tanin de Mimosa avec un surfactant servant de matrice souple, en pr\u00e9sence d\u2019eau. Ces carbones ont ensuite \u00e9t\u00e9 utilis\u00e9s pour l\u2019\u00e9limination des hydrocarbures de l\u2019eau, comme tamis mol\u00e9culaires carbon\u00e9s pour la s\u00e9paration des alcanes, ainsi que comme pr\u00e9concentrateurs pour la d\u00e9tection des compos\u00e9s organiques volatils dans l\u2019air int\u00e9rieur. La synth\u00e8se de mat\u00e9riaux mod\u00e8les ordonn\u00e9s et d\u00e9sordonn\u00e9s nous a permis de d\u00e9velopper de nouvelles m\u00e9thodes pour caract\u00e9riser pr\u00e9cis\u00e9ment leurs propri\u00e9t\u00e9s texturales et d\u2019introduire un facteur de connectivit\u00e9 hi\u00e9rarchique, mettant ainsi en \u00e9vidence l\u2019importance de la connectivit\u00e9 des carbones dans les \u00e9lectrodes de supercondensateurs.<\/p>\n\n\n\n
Nous explorons \u00e9galement d\u2019autres mol\u00e9cules biosourc\u00e9s comme pr\u00e9curseurs de mat\u00e9riaux carbon\u00e9s, destin\u00e9s notamment aux \u00e9lectrodes de piles \u00e0 combustible et d\u2019\u00e9lectrolyseurs, que je passerai bri\u00e8vement en revue.<\/p>\n\n\n\n
![\"\"](\"https:\/\/staging-scf.agence-nsw.xyz\/chimie-du-solide\/wp-content\/uploads\/sites\/28\/2026\/10\/Maurizio_Cozzi.jpg\")
<\/figure>\n<\/div>\n\n\n\n