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Scooped by
Institut de Chimie Physique
May 21, 7:37 AM
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ICP science - Communiqué CNRS : Coup de projecteur sur ces ions invisibles qui empoisonnent la vie des électrocatalyseurs
Un communiquĂ© de presse des actualitĂ©s scientifiques de lâINC Chimie du CNRS met en avant les travaux de Ba Lich Pham, Alireza Ranjbari, Abderrahmane Tadjeddine, Christophe Humbert, et leurs collaborateurs de lâIUT dâOrsay et du LOMA (UniversitĂ© de Bordeaux), publiĂ©s dans le Journal of the American Chemical Society. Ces derniers ont levĂ© le voile sur les mĂ©canismes dâempoisonnement des Ă©lectrodes de platine, constitutives des piles Ă combustible et Ă©lectrolyseurs en milieu aqueux, par les espĂšces anioniques de lâacide phosphorique en fonction du pH de la solution et du potentiel Ă©lectrique appliquĂ©. Cette premiĂšre expĂ©rimentale a Ă©tĂ© rĂ©alisĂ©e en couplant in situ la spectroscopie optique non linĂ©aire par gĂ©nĂ©ration de seconde harmonique (SHG) Ă lâĂ©lectrochimie interfaciale. Lien vers le communiquĂ© CNRS Lien vers la publication dans Journal of American Chemical Society ""Adsorption Mechanism of Phosphate Anions at PtâH2O Electrochemical Interfaces via In Situ SHG Spectroscopy"
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Institut de Chimie Physique
May 21, 8:58 AM
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ICP science - Thermal and (photo-)catalytic properties of poly(N-isopropylacrylamide)-stabilised gold nanoparticles induced by radiolysis
Tawakalit D. Abdulyekeen, Cécile Sicard-Roselli, Hynd Remita, Isabelle Lampre et leur collÚgue Vincent Huc (ICMMO) ont recemment publié un article dans New Journal of Chemistry "Thermal and (photo-)catalytic properties of poly(N-isopropylacrylamide)-stabilised gold nanoparticles induced by radiolysis" Lien vers la publication.  Gold nanoparticles (AuNPs) are widely studied due to their unique physicochemical properties, which are highly dependent on their size, shape, and composition. Efficient and environmentally friendly synthesis methods and effective stabilisation agents are essential for fabricating AuNPs with controlled sizes and shapes. This study explores the radiolytic synthesis method, a green synthesis approach using ionising radiation (gamma irradiation), and investigates the use of a thermosensitive polymer, poly(N-isopropylacrylamide) (PNIPAM), and its monomer, N-isopropylacrylamide (NIPAM), for stabilising gold nanoparticles in aqueous solutions. The resulting PNIPAM-AuNPs and NIPAM-AuNPs were spherical, homogenously dispersed, with average sizes of 5.4 nm and 3.5 nm, respectively, and exhibited high stability at room temperature over a long time. Thermal analysis revealed enhanced thermal responsiveness for PNIPAM-AuNPs, an effect not observed with the NIPAM-AuNPs. The AuNPs demonstrated excellent catalytic activity in the reduction of 4-nitrophenol (4-NP) in the presence of sodium borohydride and showed efficient plasmonic photocatalytic activity in the visible-light-driven reduction of 4-nitrothiophenol (4-NTP). These findings support the potential of radiolytically synthesised polymer-stabilised AuNPs for catalysis and environmental remediation applications.
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Institut de Chimie Physique
May 21, 8:49 AM
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ICP science - C5H6 formation in Dense Molecular Clouds
Roland Thissen, Nandana Pattathadathil et Christian Alcaraz et leurs collaborateurs ont rĂ©cemment publiĂ© un article dans Astronomy & Astrophysics "C5H6 formation in Dense Molecular Clouds". Lien vers la publication. Les mesures ont Ă©tĂ© rĂ©alisĂ©es avec le dispositif CERISES au Synchrotron SOLEIL, ces rĂ©sultats ont fait l'objet d'une communication sur le site du Synchrotron. Lien vers le communiquĂ©. "How a reactive ion turns small gas molecules into complex organics"  Context. Cyclopentadiene (C5H6) has been recognized as a crucial precursor in the formation of nonplanar polycyclic aromatic hydrocarbons (PAHs) and carbon-rich nanostructures in space. Despite its significance and detection in the Taurus Molecular Cloud (TMC-1), the elementary gas-phase reaction pathways leading to cyclopentadiene from acyclic hydrocarbon precursors remain poorly constrained. This gap is emphasized by persistent discrepancies between astrochemical model predictions and the abundances inferred from its radioastronomical detection. Aims. The aim of this work is to reconcile the chemical network that predicts the formation of C5H6 â a key intermediate in the growth of aromatic species â from gas-phase chemistry with its observed abundance in TMC-1.
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Institut de Chimie Physique
May 21, 8:43 AM
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ICP science - Supramolecular Silver Nanoparticle Hydrogels With Controlled Nanoparticle Size and Order: Synthesis Conditions and Possible Mechanism
Hynd Remita, Isabelle Lampre et leur collaborateurs ont publiĂ© rĂ©cemment un article dans CHEMNANOMAT "Supramolecular Silver Nanoparticle Hydrogels With Controlled Nanoparticle Size and Order: Synthesis Conditions and Possible Mechanism". Lien vers la publication  Nanoparticle (NP)-gel hybrid systems are multifunctional materials combining the properties of metal NPs with the structural versatility of hydrogels. They find application in advanced technologies, including controlled drug delivery, sensing, flexible electronics, and tissue engineering. Incorporation of metal NPs into a gel matrix offers structural confinement and spatial distribution of the NPs, but the control of the size, size distribution, and spatial organization remains a major challenge. In a recent work, we have shown that silver NPs of controlled size (diameter of 28.0â±â3.6 Ă
) can form two-dimensional arrays of long-range order coaligned with self-assembled fibers composed of a biobased bolaamphiphile glycolipid containing a single glucose headgroup opposite to a free carboxylic acid end-group. The straightforward self-assembly of the glycolipid with silver ions in water, followed by reduction, generates a silver NP hydrogel with an impressive order of NPs. The synthesis conditions of this process, which offers simplicity and enhanced sustainability are explored here by using and comparing various reduction methods (chemical, photochemical, and radiolytic) as well as by tuning the nature of the silver precursor. This article eventually proposes a mechanism of formation based on the excluded volume of the side-by-side assembly of four glycolipid molecules.
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Institut de Chimie Physique
May 21, 8:39 AM
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ICP science - The O•–/electron tandem path for complete mineralization of trifluoroacetate and perfluorocarboxylic acids
Zhiwen JIANG, Pierre Archirel, Mehran Mostafavi et leurs collaborateurs ont rĂ©cemment publiĂ© un article dans Nature Water "The Oâąâ/electron tandem path for complete mineralization of trifluoroacetate and perfluorocarboxylic acids". Cette Ă©tude a dĂ©jĂ Ă©tĂ© relayĂ©e par lâUniversitĂ© Paris-Saclay, CNRS Chimie, LâHumanitĂ© et Les Ăchos. Contact : Mehran Mostafavi mehran.mostafavi@universite-paris-saclay.fr Lien vers la publication  Les PFAS (pour substances per- et polyfluoroalkylĂ©es), Ă©galement appelĂ©es « polluants Ă©ternels », font rĂ©guliĂšrement la une de lâactualitĂ©. Dans la course Ă la destruction des PFAS, le âmaillon faibleâ reste souvent le mĂȘme : lâacide trifluoroacĂ©tique (TFA), le PFAS le plus court, rĂ©putĂ© quasi-indestructible. Il cristallise aujourdâhui lâenjeu des « polluants Ă©ternels ». Une Ă©tude vient toutefois bousculer les idĂ©es reçues : elle met en lumiĂšre une stratĂ©gie tandem oxydative/rĂ©ductrice (Ox/Red), pilotĂ©e par lâanion radicalaire oxygĂšne Oâąâ et lâĂ©lectron hydratĂ©, qui reconfigure en profondeur le paradigme actuel dâactivation des PFAS. Dans un milieu aqueux soumis Ă lâionisation, le TFA peut ainsi atteindre une minĂ©ralisation quasi complĂšte (â100 %) Ă tempĂ©rature ambiante et sans ajout de catalyseur. Ce mĂ©canisme est explicitĂ© par des mesures de radiolyse pulsĂ©e, qui suivent les intermĂ©diaires rĂ©actionnels dans le temps. Les radicaux nuclĂ©ophiles Oâąâ initient lâoxydation du TFA via une voie inaccessible aux radicaux âąOH, avec une constante de vitesse nettement plus Ă©levĂ©e (5,1 Ă 107 Mâ1 sâ1), conduisant Ă la formation dâun intermĂ©diaire critique, le radical CF3CO32ââą. Les rĂ©actions ultĂ©rieures avec eaqâ permettent ensuite une conversion complĂšte en Fâ et en CO32â. Au-delĂ du TFA, lâapproche permet Ă©galement la minĂ©ralisation dâacides perfluorĂ©s et perhalogĂ©nĂ©s et pourrait ĂȘtre Ă©tendue Ă des processus tandem radicalaires photo- ou photocatalytiques. Lors de la validation prĂ©-pilote sous un faisceau dâĂ©lectrons industriel, elle a atteint une vitesse record de dĂ©fluoration de 0,27 M hâ1, dĂ©montrant sa compatibilitĂ© directe avec les technologies existantes de traitement de lâeau Ă haut dĂ©bit. Ces rĂ©sultats, obtenus grĂące Ă la comprĂ©hension du mĂ©canisme rĂ©actionnel, constituent une avancĂ©e dĂ©cisive pour remĂ©dier aux problĂšmes des PFAS, en remettant en cause lâidĂ©e admise de longue date selon laquelle lâactivation des PFAS Ă chaĂźne courte serait inefficace.Â
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Institut de Chimie Physique
May 21, 8:34 AM
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ICP science - Unravelling the mysteries behind orcein dye: from orcinol-based synthesis to molecular degradation
Sylvie HĂ©ron, Alain Tchapla et leurs collaborateurs du MusĂ©um d'Histoire Naturelle et du Laboratoire de Recherche des Monuments Historiques ont rĂ©cemment publiĂ© un article dans Dyes and Pigments "Unravelling the mysteries behind orcein dye: from orcinol-based synthesis to molecular degradation"  Lien vers la publication  This study aims to identify the various reasons behind the wide range of colours of orchil dye. The first step was to study the impact of synthesis parameters on colour and chemical composition variation, while the second step aimed to study chemical degradation with the artificial ageing protocol. Variation in reactant concentration, ammonia level and O2 availability led to red-orange or purple-coloured solutions. HPLC-DAD-MS, UV-Vis absorption and reflectance analysis enabled both molecular identification and objective colour characterisation of each solution. Thanks to PLS regression, the contribution of the relative content of each molecule to observed colour of the dye could be determined. Finally, accelerated light-ageing experiments assessed the stability of the synthesised dyes. Molecules responsible for the purple hue (ÎČ- and Îł-orceins) were found to be significantly more sensitive to photodegradation than those associated with red-orange shades (α-orceins).
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Institut de Chimie Physique
May 21, 7:50 AM
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ICP science - Experimentally recreated workplace environments contain submicron crystalline silica particles, including ultrafine particles, which have been identified in the mediastinal lymph node...
Dominique Bazin et ses collaborateurs ont recemment publiĂ© un article dans BMJ "Experimentally recreated workplace environments contain submicron crystalline silica particles, including ultrafine particles, which have been identified in the mediastinal lymph nodes of construction workers" Lien vers la publication  Although ultrafine particles are suspected to contribute significantly to occupational exposure to crystalline silica, they have not yet been definitively identified in workplaces or human tissues. Particles were generated in three 60-minute tests in a glove box: cutting kerb or granite pavement, drilling solid cinder block. The particle concentrations per cm3 of air in the box and their mean size were analysed online and using transmission electron microscopy and energy dispersive X-ray analysis (EDX). 17 mediastinal lymph node (MLN) samples from construction workers who underwent lung cancer surgery were examined by Fourier transform infrared spectroscopy (FTIR) and 8/17 by scanning electron microscopy (SEM) with EDX analysis. The particle concentration was high when cutting kerb or granite pavement (10â000â20 000âcmâ3 and 50â000â160â000âcmâ3, respectively), while below 1000 cmâ3 for drilling cinder block. The aerosol consisted mainly of submicron emissions with a nanometric fraction (ie, <100ânm), showing two main modes: 351 nm to 16 nm for kerb, 407 nm to <16ânm for granite pavement and 310 nm to 17 nm for cinder block processing. Ultrafine silica particles were only identified in kerb and granite cutting samples. Analysis using FTIR revealed an Si signal in 15/17 of the MLN samples and SEM and EDX analysis detected geometric particle deposition with Si spectra, particularly nano-sized particles, in the eight analysed samples. Ultrafine silica particles are produced in conditions that mimic typical construction work processes, but the quantity produced varies according to the task. Similar characteristics were observed in ultrafine silica particles in both MLN samples and experimental aerosols.
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Institut de Chimie Physique
May 21, 7:20 AM
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ICP science - The absolute cross-section of the reactive collision of P + ( 3 P) with D 2 : a combined theoretical and experimental study
Christian Alcaraz, Roland Thissen et leurs collaborateurs ont rĂ©cemment publiĂ© un article dans Physical Chemistry Chemical Physics "The absolute cross-section of the reactive collision of P + ( 3 P) with D 2 : a combined theoretical and experimental study". Les mesures ont Ă©tĂ© rĂ©alisĂ©es au Synchrotron SOLEIL grĂące Ă l'utilisation du dispositif CERISES. Lien vers la publication  In this work, we combine theoretical and experimental methods to study the P+(3P) + D2 â PD+ + D reaction. As a result, the absolute cross-section as a function of collision energy is obtained. Experimentally, the cross-section is measured using the guided ion beam technique (GIB), where P+ is produced by VUV photons at the SOLEIL synchrotron using PCl3 as a precursor. Theoretically, the cross-section is calculated from first principles. The potential energy surfaces of the three electronic states correlating with the P+(3P) are constructed by fitting MRCI points, and reaction dynamics are performed on each of them independently, hence neglecting couplings. The total cross-section is then obtained from the weighted contribution of each considered electronic state. Our findings show good agreement between the measured and calculated cross-sections, with a small discrepancy indicating that spinâorbit and non-adiabatic coupling, not considered in this work, may play a role in this reaction. The results hereafter presented demonstrate that the chemistry of the third-row atomic cations with molecular hydrogen is generally unfavoured, unlike their second-row homologues, thus manifesting the existence of boundaries to the applicability of the so-called chemical analogy (i.e., assuming the same chemical behaviour for elements belonging to the same group).
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Institut de Chimie Physique
May 21, 9:37 AM
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ICP actualité - Soutenance HDR Marine de Person
Marine de Person du groupe CAPRI a soutenu avec succÚs son Habilitation à Diriger des Recherches le mardi 5 mai 2026.  "Analyse de lipides et substances analogues par chromatographie en phase liquide couplée à la spectrométrie de masse (HPLC-MS/MS)".  Félicitations Marine!
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Institut de Chimie Physique
May 21, 9:33 AM
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ICP actualité - A Chemist’s Guide to Valence Bond Theory, 2nd Edition (Wiley)
Philippe Hiberty (groupe Theosim) has just published a book entitled âA Chemistâs Guide to Valence Bond Theory, 2nd Editionâ. Lien vers la publication  This books is primarily aimed at chemists, be they experimentalists, theoreticians and teachers. It explains how to use valence bond (VB) theory to think concisely and rigorously in chemical and photochemical applications and how to use VB computations. It first teaches the basic principles of VB theory such as hybridization, resonance energy and the nature of various types of chemical bonds, and sets bridges to Molecular Orbital theory. In passing, it addresses the alleged failures often associated to VB theory (ground state of dioxygen, hybridization vs. photoelectron spectroscopy, aromaticity, and so on) and shows them to be all mythical. A VB-based reactivity model is presented, allowing one to predict reactions barriers from easily accessible properties of reactants. All these applications include sets of exercises and corresponding answers. On the computational side, the book familiarizes the reader with the various VB-based computational tools and methods available today. The last chapter describes the Breathing-Orbital VB method, originating from the ICP, aimed at providing very compact VB wave functions approaching chemical accuracy by treating dynamic electron correlation in a direct and cost-efficient way. Â
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Institut de Chimie Physique
May 21, 9:27 AM
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ICP agenda - PhD Days de l'ICP
Le PhD Day à l'ICP aura lieu le 5 juin 2026. Au programme (à venir) : communications orales et session poster. Venez nombreux !
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Institut de Chimie Physique
May 21, 10:25 AM
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UPSaclay - la 11ème Journée de l'Ecole Doctorale 2MIB aura lieu le 16 juin
La onziĂšme JournĂ©e de l'Ecole Doctorale 2MIB aura lieu Ă partir de 12:45 le mardi 16 juin 2026 Ă lâENS Paris-Saclay (Gif-sur-Yvette). AprĂšs une brĂšve introduction proposĂ©e par la Graduate School de Chimie et le directeur de lâEcole doctorale, GĂ©raldine Masson, de lâICSN (Institut de Chimie des Substances Naturelles, CNRS), membre du bureau de lâED 2MIB et mĂ©daille dâargent du CNRS assurera la confĂ©rence plĂ©niĂšre. Vous serez ensuite invitĂ©s Ă assister aux prĂ©sentations orales proposĂ©es par des Ă©tudiants des trois pĂŽles de l'Ă©cole doctorale (qui se dĂ©rouleront en trois sessions parallĂšles) :  - CIM (Chimie Inorganique et MatĂ©riaux) - COB (Chimie Organique et BiomolĂ©culaire) - CPBA (Chimie Physique, BioPhysique et Analytique) .  Dans lâaprĂšs-midi, dâautres doctorants des trois pĂŽles de lâED 2MIB prĂ©senteront leurs travaux Ă lâoccasion dâune session posters.  Date limite dâinscription pour toute participation simple : 1er juin Inscription Ă lâĂ©vĂ©nement Â
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Institut de Chimie Physique
May 21, 10:11 AM
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UPSaclay - Conférences et Workshops : IA et pédagogie pour la formation des formateurs
La Graduate School Ăducation, Formation, Enseignement (GS EFE) et l'Institut DataIA de lâUniversitĂ© Paris-Saclay, en collaboration avec la DĂ©lĂ©gation RĂ©gionale et AcadĂ©mique du NumĂ©rique Ăducatif (DRANE) Ăle de France, organisent le 17 juin 2026, de 9h Ă 17h au LUMEN une journĂ©e consacrĂ©e Ă lâIA au service de la formation des formateurs. DestinĂ© aux enseignants, futurs enseignants et acteurs de la formation (sans prĂ©requis en intelligence artificielle et hors public expert de lâIA) cet Ă©vĂ©nement proposera des Ă©changes et des ateliers autour des usages pĂ©dagogiques de l'IA, de ses enjeux Ă©thiques et de ses impacts sur les pratiques Ă©ducatives. Le programme complet Des ateliers sont prĂ©vus, merci de prĂ©voir de vous munir dâun ordinateur portable. Inscription gratuite et obligatoire Date & horaires : Rendez-vous le 17 juin 2026 de 9h Ă 17h Lieux : đ LUMEN â UniversitĂ© Paris-Saclay - 8 avenue des Sciences, 91190 Gif-sur-Yvette
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Institut de Chimie Physique
May 21, 10:00 AM
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UPSaclay - Programme post-doctoral UPSaclay-STAR-φ
La Graduate School de physique de lâUniversitĂ© Paris-Saclay lance un deuxiĂšme appel Ă candidatures dans le cadre de son programme de bourses postdoctorales : UPSaclay-STAR-Ï, soutenu par le programme europĂ©en Marie SkĆodowska-Curie COFUND (appel 2024). Date limite de candidature : 15 juillet 2026. DĂ©but prĂ©vu des bourses : dĂ©but 2027 (flexible jusqu'en octobre 2027). Lien vers le site Cet appel permettra de recruter jusquâĂ 22 chercheurs postdoctoraux internationaux pour des projets de recherche de 24 mois au sein de lâun des 40 laboratoires de la Graduate School, au synchrotron SOLEIL ou au Laboratoire national de mĂ©trologie (LNE). Les candidats devront proposer un projet de recherche original, en lien avec les vastes domaines d'expertise de la Graduate School et de ses partenaires, allant de la physique fondamentale Ă la physique appliquĂ©e.  Â
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Institut de Chimie Physique
May 21, 10:06 AM
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UPSaclay - Appel à projets prématuration des Graduate Schools et Institut dans le cadre de A2-LINE.
LâAAP PREMATURATION GS/I a pour objectif de soutenir financiĂšrement et dâaccompagner les projets Ă trĂšs bas niveau de maturitĂ© technologique et Ă fort potentiel innovant, portĂ©s par des chercheurs, chercheuses, enseignants-chercheurs, enseignantes chercheuses, ingĂ©nieurs ou ingĂ©nieures, relevant des 235 laboratoires des 18 Graduate Schools et Institut. Co-financĂ©s par la RĂ©gion Ile-de-France dans le cadre du Fonds europĂ©en de dĂ©veloppement rĂ©gional (FEDER) au travers du projet A2-LINE, les projets laurĂ©ats devront s'inscrire dans les Domaines dâInnovation StratĂ©giques de la RĂ©gion Ăle-de-France et bĂ©nĂ©ficieront du financement d'un an de salaire dâingĂ©nieur ou post-doctorant. En amont de leur candidature, les porteuses et porteurs de projets sont invité·es Ă contacter leur Graduate School ou Institut (pour assurer la validation du financement) ainsi que la structure de valorisation de leur Ă©tablissement tutelle gestionnaire. Le dossier de candidature est Ă dĂ©poser sur la plateforme dĂ©diĂ©e avant le 9 Juin 2026 Ă 12h. Lien vers le site
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Institut de Chimie Physique
May 21, 10:38 AM
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Evénement - 5ème édition de l'école d'été "Physico-chimie et problématiques sociétales contemporaines" de la fédération de Chimie-Physique de Paris-Saclay (CPPS)
La 5Ăšme Ă©dition de l'Ă©cole d'Ă©tĂ© "Physico-chimie et problĂ©matiques sociĂ©tales contemporaines"  de la fĂ©dĂ©ration de Chimie-Physique de Paris-Saclay (CPPS) se tiendra du 29 juin (14h) au 3 juillet (16h) sur le campus de lâUniversitĂ© Paris-Saclay. Cette Ă©cole s'adresse plus particuliĂšrement aux Ă©tudiants de L2 au M2 (magistĂšre ou non), souhaitant nourrir leur rĂ©flexion sur leur futur parcours ou dĂ©couvrir les thĂ©matiques dĂ©veloppĂ©es Ă Paris-Saclay Ă l'interface de la Chimie et de la Physique.  Lâobjectif est de prĂ©senter les grands enjeux sociĂ©taux oĂč la Chimie-Physique joue un rĂŽle clĂ©. Le programme s'articule autour de cinq thĂ©matiques majeures (une par jour), explorĂ©es Ă travers de petits cours/prĂ©sentations, des visites d'installations expĂ©rimentales et des travaux pratiques : BiomolĂ©cules : Comprendre la relation structure-activitĂ© de molĂ©cules biologiques pour le design de nouveaux mĂ©dicaments ou la photostabilitĂ© des molĂ©cules du vivant. Astrophysique & Astrochimie : Ătudier la matiĂšre interstellaire. Patrimoine & ArchĂ©ologie : Utiliser les techniques analytiques pour documenter l'histoire et crĂ©er les matĂ©riaux durables, palĂ©o-inspirĂ©s, de demain. MĂ©thodes biophysiques et biochimiques pour la santĂ© & lâenvironnement : Allier approches expĂ©rimentales et thĂ©oriques complĂ©mentaires pour optimiser les outils molĂ©culaires nĂ©cessaires Ă la comprĂ©hension de la machinerie cellulaire ou la dĂ©tection de polluants. Technologies quantiques : MaĂźtriser les processus molĂ©culaires par lasers ultrarapides pour une chimie plus efficace. Cette Ă©cole vous permettra de dĂ©couvrir des approches de pointe telles que les  spectroscopies laser (femtoseconde/attoseconde), la spectromĂ©trie de masse, la RMN, la microscopie AFM couplĂ©e Ă lâIR et la modĂ©lisation numĂ©rique.  Informations pratiques : Frais : L'inscription est totalement gratuite. Repas : Les dĂ©jeuners (du mardi au vendredi) sont offerts par la FĂ©dĂ©ration CPPS. Inscriptions Stage : Si vous ĂȘtes en stage durant cette pĂ©riode, n'oubliez pas d'en informer votre responsable afin d'effectuer, si nĂ©cessaire, un avenant Ă votre convention.
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Institut de Chimie Physique
May 21, 10:54 AM
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Evènement - Une 1/2 journée scientifique ChemoSensium le 1er juillet au Lumen
Pour mettre en place le rĂ©seau ChemoSensium au sein des Ă©quipes de Paris-Saclay, les Graduate Schools Chimie et HeaDS organisent une demi journĂ©e scientifique sur les thĂ©matiques de ChemoSensium le mercredi 1er juillet 2026, au Lumen (8 avenue des sciences). L'Ă©vĂšnement dĂ©butera Ă midi par un cocktail sensoriel dĂ©jeunatoire, il sera suivi par quatre interventions et des animations autour du goĂ»t et de lâodorat. Lâinscription est gratuite avec rĂ©servation obligatoire avant le 24 juin
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Institut de Chimie Physique
May 22, 3:57 AM
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Evènement - Colloque CNRS « Santé-environnement : comprendre, prévenir, agir » les 9 et 10 juillet 2026
Le comitĂ© scientifique santĂ© du CNRS a le plaisir de vous convier au Colloque « SantĂ©-environnement : comprendre, prĂ©venir, agir 2026 - MITI" qui se tiendra les 9 et 10 juillet 2026 au siĂšge du CNRS. NâhĂ©sitez pas Ă vous inscrire, ce colloque est ouvert Ă tout le monde ! Ce colloque comporte Ă©galement un volet prospectif, prĂ©parĂ© en amont et poursuivi pendant le colloque sous forme dâateliers. Ce volet a pour but dâidentifier collectivement les prioritĂ©s scientifiques et les dispositifs structurants nĂ©cessaires au dĂ©veloppement de la recherche Ă lâinterface santĂ©âenvironnement pour les annĂ©es Ă venir. Les contributions alimenteront des fiches prospectives CNRS en santĂ© environnement, en appui aux stratĂ©gies et aux travaux du comitĂ© scientifique santĂ© du CNRS et de ses instituts. Dans ce cadre, un questionnaire court est diffusĂ© afin de recueillir vos avis. Nous vous remercions par avance pour votre participation Ă cette rĂ©flexion collective dâici le 31 mai 2026 (5-10 min, 6 questions) : Questionnaire Programme et inscriptionÂ
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Institut de Chimie Physique
May 21, 11:15 AM
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Prix - Call for Nomination 2027 L’Oréal-UNESCO For Women in Science International Awards
The Call for Nomination 2027 LâOrĂ©al-UNESCO For Women in Science International Awards is now open.  The 2027 Awards will designate five outstanding researchers in Physics, Mathematics, Computer and Information Sciences, Chemistry, Earth & Related Environmental Sciences. Link to the website Call for application/nomination from April 6 to June 30 2026.
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Institut de Chimie Physique
May 21, 7:13 AM
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Institut de Chimie Physique
March 12, 3:22 AM
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Souad Abou Zeid, Liran Hu, Samy Remita et leurs collaborateurs ont rĂ©cemment publiĂ© un article dans Materials Chemistry Frontiers "Radiolytic synthesis of rGOâPEDOT nanohybrids with enhanced functional properties" Lien vers la publication  Hybrid reduced graphene oxideâpoly(3,4-ethylenedioxythiophene) (rGOâPEDOT) nanocomposites were synthesized via green gamma-radiolysis under ambient conditions, without dopants or catalysts. Three distinct synthesis routesâincluding one-step simultaneous radiation induced reduction of aqueous graphene oxide (GO) and EDOT monomers and two-step approaches involving the reduction of GO in the presence of pre-formed PEDOT oligomers or polymersâwere explored to assess the impact of absorbed dose and polymerization stage on the physicochemical and functional properties of the resulting materials. Extensive characterization techniques revealed that gamma-irradiation promotes effective GO reduction and controlled PEDOT polymerization, leading to significant band gap narrowing, enhanced structural ordering, and substantial increase in the carbon-to-oxygen atomic ratio (from 3.7 to 9.3) indicative of effective reduction and improved conjugation within the nanocomposites. Visual evolution confirmed kinetic-controlled composite formation, yielding hydrogel-like aggregates. Morphological analyses showed well-dispersed PEDOT on rGO sheets, contributing to improved thermal stability, enhanced optoelectronic properties and superior electrochemical performance. The composites exhibited enhanced specific capacitances up to âŒ248 F gâ1, surpassing many reported PEDOT-based materials, attributed to the synergistic combination of rGO's conductive network and PEDOT's pseudocapacitance. This green, catalyst-free, and scalable methodology offers a promising platform for fabricating multifunctional hybrid materials with potential applications in flexible electronics, energy storage devices, and sensing technologies.
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Scooped by
Institut de Chimie Physique
March 12, 3:15 AM
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Emeline Boyer, Carine ClavaguĂ©ra et leurs collaborateurs viennent de publier un article dans The Journal of Physical Chemistry B "Modeling the Vibrational Circular Dichroism Spectroscopy of Phenylcyclohexanediol Solvated in Dimethyl Sulfoxide Using Polarizable Molecular Dynamics". Ce travail se place dans le cadre du projet ANR Dichrosol (ISMO, ICP, LIPhy, CPCV). Lien vers la publication  Modeling vibrational circular dichroism (VCD) spectra in solution remains a complex task due to the intricate interactions involved. Recent advances in computational chemistry, particularly the implementation of polarizable force fields, have greatly improved the description of environmental effects in classical molecular dynamics simulations. In this study, we use the AMOEBA polarizable model to calculate VCD spectra through the expression of the electric and magnetic dipole moments developed recently [Bowles, J. . ChemPhysChem 2024, 25, e202300982.] in combination with the use of induced dipole models. This methodology enables the reliable treatment of flexible molecules and has been applied to the 1-Phenyl-1,2-Cyclohexanediol (PC) molecule solvated in dimethyl sulfoxide (DMSO). The computed infrared and VCD spectra provide detailed insights into molecular conformations and soluteâsolvent interactions. An in-depth investigation was conducted into the possible effects of system size, concentration, and spectral convergence. Comparison with experimental vibrational frequencies in deuterated solvent further supports the interpretation of spectral features, although residual differences in the spectral shifts and broadenings prove to be challenging for theory, especially in the case of VCD.
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Scooped by
Institut de Chimie Physique
March 12, 3:41 AM
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Roland Thissen et ses collaborateurs ont récemment publié un article dans Icarus "Ion induced formation of complex organic nitrogen molecules in solid-phase adenine" Lien vers la publication  Complex organic molecules have been found in many space environments like meteorites and comets. There, they are subjected to various forms of radiation (photons, electrons, ions), opening the question of their behavior and chemical evolution, which may have played a crucial role in chemical processes of astrobiological interest. In this study, we investigate the irradiation of adenine (CHN) with oxygen and neon ions. The free parameters of the experiments include varying energies (30-70 keV), temperatures (150, 300 K), sample thicknesses (138-554 nm), and ion fluences (0.69-5  10 ions cm). In situ IR spectroscopy reveals the appearance of CN and N=C=N bands indicating the formation of new species. Ex situ ultra-high-resolution mass spectrometry shows the formation of new complex organic molecules that far exceed the molecular mass of adenine. These macromolecules show great chemical diversity and can be expressed as (HCN)R families, where z can reach 14 and R can be C, H, N, NH, CH or CN. In total, nearly 100 individual families have been identified, 28 of which can be found in every irradiated sample. Their aromaticity equivalent is higher than that in other N-rich samples such as Titan tholins and HCN-polymers, corresponding to polycyclic aromatic nitrogen-bearing hydrocarbons. The high amount of nitrogen in these molecules indicates a very efficient incorporation of nitrogen in the solid phase during the irradiation of adenine. The ease with which complex organic matter forms through irradiation highlights the relevance of these species in space environments.
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Scooped by
Institut de Chimie Physique
March 12, 3:29 AM
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Souad Abou Zeid, Liran Hu, Samy Remita et leurs collaborateurs ont publiĂ© un article dans Materials Chemistry Frontiers "Gamma-induced one-step synthesis of reduced graphene oxideâsilver nanoparticles with enhanced properties". Lien vers la publication  This study presents a novel gamma-induced one-pot synthesis of reduced graphene oxideâsilver nanoparticle (rGOâAg NPs) nanocomposites. Syntheses were conducted in a deoxygenated aqueous medium containing 0.2 g Lâ1 graphene oxide (GO), silver ions (10â3 or 10â2 mol Lâ1), and 0.2 mol Lâ1 isopropanol at ambient temperature and pressure. Multi-technique characterization confirmed the reduction of GO and silver ions, forming nanocomposites with significantly improved physicochemical and electrochemical properties compared to pristine GO, rGO alone, and rGOâAg NPs prepared by other methods. UV-Vis absorption spectroscopy revealed tunable optical properties, while UPS measurements provided insights into the energy band structure, highlighting interactions between rGO and Ag NPs that enhance electronic properties. XPS and ATR-FTIR confirmed the successful reduction processes. SEMâEDX analyses demonstrated uniform silver nanoparticle distribution on rGO sheets. The C/O ratio significantly increased after irradiation, with values of 10.8 and 9.6 for composites synthesized with 10â3 and 10â2 mol Lâ1 in silver ions, respectively, compared to 11.2 for rGO alone. Raman spectroscopy showed a lower intensity ratio (ID/IG) between D and G bands (1.18 for nanocomposites vs. 1.40 for rGO), indicating fewer structural defects. Improved thermal stability was evidenced by reduced weight loss (10%) at 300â800 °C. Electrochemical studies revealed exceptional specific capacitance values of 218 F gâ1 (10â3 mol Lâ1 Ag+ at 50 kGy) and 298 F gâ1 (10â2 mol Lâ1 Ag+ at 70 kGy), surpassing the 125.4 F gâ1 for rGO alone. These findings highlight the potential of gamma-induced synthesis for producing rGOâAg NPs nanocomposites for high-performance supercapacitor applications.
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Scooped by
Institut de Chimie Physique
March 12, 3:36 AM
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Meriem Baziz, Liran Hu, Samy Remita et leurs collaborateurs ont publiĂ© un article dans Polmer Bulletin : "Elaboration of Novel Biocomposite Hydrogel Polymers made of Alginate and Sepiolite and endowed with Enhanced Properties" Lien vers la publication  Nowadays growing attention is given to the design and development of novel interpenetrating polymer networks (IPN) from the combination of hydrogel polymers loaded with natural clay. In this work, we used the eco-friendly IPN strategy to develop novel hydrogel biocomposite beads, made of alginate (ALG), with improved clay dispersion, higher pH sensitivity, better stretchability and swellability, together with enhanced regenerability properties and delayed biodegradability. Fibrous clay, namely, sodium sepiolite (NaS), was loaded into alginate simple biocomposite network (SBN) beads, via manual co-grinding mixture/encapsulation method, at different sepiolite loads. Alginate double biocomposite network (DBN) beads were also prepared at different sepiolite loads, via the diffusion of acrylamide monomers (AAM) inside alginate single biocomposite network (SBN) beads, followed by external and in situ free radical polymerization of AAM into polyacrylamide (pAAM), using ammonium persulfate (APS) as polymerization initiator and N,N-methylenebisacrylamide (Bis) as covalent crosslinker agent. The as-elaborated SBN and DBN beads were then characterized by digital camera recording, XRD analysis, ATR-FTIR characterization and SEM observation. FTIR results showed that NaS and pAAM were successfully incorporated into DBN beads, while partially exfoliated morphology was obtained with XRD analysis, which revealed the enhancement of fibrous clay dispersion, even at relatively high sepiolite loads. Besides, SEM microscopy confirmed the porous spongious nature of DBN beads. The properties of the as-elaborated SBN and DBN beads were also evaluated by test touching, swelling rate measurements, adsorption/desorption experiments and biodegradability evaluation. DBN beads properties were always found enhanced in comparison with those of SBN beads. This suggests that the synergetic effect between IPN and biocomposite structure improves the stretchability of the DBN beads, their stability in water whatever the pH and their swelling behavior (up to 2000 g/g adsorbed water after 110 min, which was nevertheless found dependent on the pH and on sepiolite load). Moreover, DBN beads displayed enhanced adsorption/desorption properties toward methylene blue (MB) dye (no reduction in MB adsorption capacity after 5 cycles), very good regenerability (ethanol being used as effective eluting agent) and delayed biodegradability (complete degradation only after 8 days in the presence of sepiolite). In summary, this work showed an interesting and safe IPN/biocomposite approach to develop high-performance alginate biocomposite polymers as a promising system toward their use in eco-friendly processes.Â
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