BEGIN:VCALENDAR VERSION:2.0 PRODID:-//IMN - ECPv6.15.18//NONSGML v1.0//EN CALSCALE:GREGORIAN METHOD:PUBLISH X-ORIGINAL-URL:https://www.cnrs-imn.fr/en/ X-WR-CALDESC:Events for IMN REFRESH-INTERVAL;VALUE=DURATION:PT1H X-Robots-Tag:noindex X-PUBLISHED-TTL:PT1H BEGIN:VTIMEZONE TZID:Europe/Paris BEGIN:DAYLIGHT TZOFFSETFROM:+0100 TZOFFSETTO:+0200 TZNAME:CEST DTSTART:20250330T010000 END:DAYLIGHT BEGIN:STANDARD TZOFFSETFROM:+0200 TZOFFSETTO:+0100 TZNAME:CET DTSTART:20251026T010000 END:STANDARD BEGIN:DAYLIGHT TZOFFSETFROM:+0100 TZOFFSETTO:+0200 TZNAME:CEST DTSTART:20260329T010000 END:DAYLIGHT BEGIN:STANDARD TZOFFSETFROM:+0200 TZOFFSETTO:+0100 TZNAME:CET DTSTART:20261025T010000 END:STANDARD BEGIN:DAYLIGHT TZOFFSETFROM:+0100 TZOFFSETTO:+0200 TZNAME:CEST DTSTART:20270328T010000 END:DAYLIGHT BEGIN:STANDARD TZOFFSETFROM:+0200 TZOFFSETTO:+0100 TZNAME:CET DTSTART:20271031T010000 END:STANDARD END:VTIMEZONE BEGIN:VEVENT DTSTART;TZID=Europe/Paris:20260205T090000 DTEND;TZID=Europe/Paris:20260205T120000 DTSTAMP:20260409T230443 CREATED:20260123T095352Z LAST-MODIFIED:20260123T095352Z UID:3772-1770282000-1770292800@www.cnrs-imn.fr SUMMARY:XPS Theoretical Training DESCRIPTION: URL:https://www.cnrs-imn.fr/en/event/xps-theoretical-training/ LOCATION:Amphi IMN END:VEVENT BEGIN:VEVENT DTSTART;TZID=Europe/Paris:20260212T133000 DTEND;TZID=Europe/Paris:20260212T170000 DTSTAMP:20260409T230443 CREATED:20260129T171640Z LAST-MODIFIED:20260409T083106Z UID:3771-1770903000-1770915600@www.cnrs-imn.fr SUMMARY:Solid State Chemistry Seminar - Camila Campos (IMEC Belgium) DESCRIPTION:Camila Campos (IMEC Belgium) \nExploiting the electric response of materials for improved analytical performance URL:https://www.cnrs-imn.fr/en/event/solid-state-chemistry-seminar-camila-campos-imec-belgium/ LOCATION:Videoconferencing ATTACH;FMTTYPE=image/jpeg:https://www.cnrs-imn.fr/wp-content/uploads/2026/01/Camila_Campos.jpg END:VEVENT BEGIN:VEVENT DTSTART;TZID=Europe/Paris:20260213T093000 DTEND;TZID=Europe/Paris:20260213T120000 DTSTAMP:20260409T230443 CREATED:20260129T171722Z LAST-MODIFIED:20260409T125851Z UID:3435-1770975000-1770984000@www.cnrs-imn.fr SUMMARY:Thesis defense of Aswadh S. SAJEEVAN (ST2E) DESCRIPTION:Friday\, February 13 at 9:30 a.m.\n \n\nLi-Organic Solid Polymer Electrolyte Batteries: Integration of Lithiated p-Dihydroxyterephthalate Salts\, Electrochemical Properties and Recycling Strategy\nSummary: Organic electrode materials offer a promising route to the development of more sustainable batteries\, by reducing dependence on critical metals. Among them\, p-dihydroxyterephthalate derivatives feature high operating potentials and scalable structures. This thesis investigates how their redox properties\, electrode architecture and compatibility with solid polymer electrolytes can be optimized to improve the performance of lithium-organic batteries. \nThe first part examines zinc(II) (2\,5-dilithium-oxy)-terephthalate\, which adopts a lamellar structure and exhibits stable monoelectronic electrochemical activity at a potential of 3.4 V vs. Li+/Li. The second part evaluates magnesium and zinc derivatives in flexible all-solid-state cells using poly(e-caprolactone-trimethylene carbonate) electrolytes. At 60°C\, the polymer electrolyte ensures high ionic conductivity and performance comparable to that observed with liquid electrolytes. The third section focuses on copper(II) (2\,5-dilithium-oxy)terephthalate. Although the bulk material exhibits limited electrochemical activity due to large aggregates\, the synthesis of a carbon-based composite with high specific surface area leads to a nanostructured system that provides access to the full faradic capacity of this organic structure\, but at the expense of sufficient cycling stability. Finally\, the fourth section reports on a pioneering study into the recycling of magnesium(II) (2\,5-dilithium-oxy)-terephthalate-based electrodes. \nKey words: Organic electrode materials\, Polymer electrolytes\, Battery recycling\, Lithium batteries. \n\nTowards Soft Solid-State Li-Organic Batteries: Implementation of Lithiated p-Dihydroxyterephthalate-Based Positive Electrode Materials\, Electrochemical Properties\, and Recycling Strategy\nAbstract: Organic electrode materials offer a promising route toward sustainable lithium-based batteries by reducing reliance on scarce metals. Among these\, p-dihydroxyterephthalate derivatives provide high operating potentials and tunable structures. This thesis investigates how their redox properties\, electrode architecture\, and compatibility with solid polymer electrolytes can be optimized for improved performance. \nThe first part examines zinc(II) (2\,5-dilithiumoxy)-terephthalate\, which forms a lamellar structure and shows stable one-electron activity near 3.4 V vs Li+/Li. The second part evaluates magnesium and zinc derivatives of this material in soft solid-state cells with poly(e-caprolactoneco-trimethylene carbonate) based solid polymer electrolytes. At 60 °C\, the polymer electrolyte provides high ionic conductivity and delivers performance comparable to that observed with liquid electrolytes. The third part focuses on copper(II) (2\,5-dilithium-oxy)-terephthalate. Although the bulk material shows limited electrochemical activity due to large aggregates\, the synthesis of a composite based on high surface area carbon yields a nanostructured system that enables access to the full faradaic capacity of this organic framework\, albeit at the expense of adequate cycling stability. Finally\, the fourth part reports a pioneering study on the recycling of magnesium-based (2\,5-dilithium-oxy)-terephthalate electrodes. \nKeywords: Organic electrode materials\, Polymer electrolytes\, Battery recycling\, Lithium batteries URL:https://www.cnrs-imn.fr/en/event/thesis-defense-of-aswadh-s-sajeevan-st2e/ LOCATION:Amphi IMN ATTACH;FMTTYPE=image/jpeg:https://www.cnrs-imn.fr/wp-content/uploads/2026/01/SAJEEVAN_Aswadh.jpg END:VEVENT BEGIN:VEVENT DTSTART;TZID=Europe/Paris:20260306T093000 DTEND;TZID=Europe/Paris:20260306T093000 DTSTAMP:20260409T230443 CREATED:20260224T145100Z LAST-MODIFIED:20260409T131239Z UID:3602-1772789400-1772789400@www.cnrs-imn.fr SUMMARY:Raymonda DIAB's thesis defense (co-dir. ST2E) DESCRIPTION:Towards Fast and Safe Recharging of Li-ion Batteries: Design\, Parameterization and Experimental Validation of a Pseudo-2D Electrochemical Model Based on Homogenization\nAbstract: Fast charging of lithium-ion batteries remains a major challenge due to degradation\, safety risks and ageing. Preventing lithium metal deposition during fast charging requires dynamic current adjustment to keep the negative electrode potential above 0 V vs. Li+/Li. Since this potential is inaccessible to direct measurement in commercial batteries\, we propose a new variant of the pseudo-bidimensional electrochemical model\, enabling real-time estimation of the potential profile across the thickness of the electrodes. A non-linear state representation is obtained from the coupled partial differential equations of the system\, via an electrode homogenization approach and non-uniform grid discretization. Experimental parameterization of the model is performed using a three-electrode setup. The model exhibits robust numerical stability\, enabling reliable simulations down to 10C. Finally\, its predictive capability is demonstrated by validation coupled with parameter estimation for constant load regimes between 2C and 6C. \nKeywords: Lithium-ion battery\, Fast charging\, Pseudo-2D model\, Parameterization\, Homogenization technique\, Lithium deposition \n\nTowards Safe Fast Charging of Li-ion Batteries: Design\, Parameterization\, and Experimental Validation of a Homogenization-Based Pseudo-2D Electrochemical Model\nAbstract: Despite the growing demand for shorter charging times\, fast charging of lithium-ion batteries remains challenging due to performance degradation\, safety risks\, and aging constraints. Preventing lithium plating during fast charging necessitates dynamically adjusting the charging current to keep the negative electrode potential above 0 V vs. Li+/Li. As this potential is not directly measurable in commercial cells\, this work develops a novel pseudo-two-dimensional electrochemical model variant. The model enables realtime estimation of the through-thickness potential profile in each electrode. Derived from coupled partial differential equations via electrode homogenization and a non-uniform grid\, the model is formulated as a non-linear statespace system. The experimental parameterization of the model is achieved using a threeelectrode assembly. The model demonstrates robust numerical stability\, enabling reliable simulations at rates as high as 10C. Finally\, the model’s predictive capability is demonstrated through simultaneous validation and parameter estimation across charging rates of 2C to 6C. \nKeywords: Lithium-ion battery\, Fast charging\, Pseudo-2D model\, Parametrization\, Homogenization Technique\, Lithium plating URL:https://www.cnrs-imn.fr/en/event/raymonda-diabs-thesis-defense-co-dir-st2e/ LOCATION:IREENA Saint-Nazaire ATTACH;FMTTYPE=image/jpeg:https://www.cnrs-imn.fr/wp-content/uploads/2026/02/diab_raymonda.jpg END:VEVENT BEGIN:VEVENT DTSTART;TZID=Europe/Paris:20260311T140000 DTEND;TZID=Europe/Paris:20260311T160000 DTSTAMP:20260409T230443 CREATED:20260306T161929Z LAST-MODIFIED:20260306T161929Z UID:3430-1773237600-1773244800@www.cnrs-imn.fr SUMMARY:George HARRINGTON Seminar DESCRIPTION:Wednesday\, March 11 at 2:00 pm -Amphi IMN \n \nGeorge HARRINGTON\nDepartment of Chemistry at Bath University\, UK \n  \nMaterials chemistry challenges in the green energy transition: From electrode kinetics to scalable recycling routes\n\n  \nAbstract \nThe global transition toward green and sustainable energy systems presents a series of challenges from a materials chemistry perspective. Central among these is the need to develop energy-conversion and storage technologies that are efficient\, high-performing\, and durable over operational lifetimes. Equally critical is the requirement that the manufacturing of these devices be scalable within the constraints of raw material supply and designed with viable end-of-life pathways. \nThe first part of this seminar focuses on developing approaches to improve the performance solid oxide cells (SOCs)\, key technologies capable of decoupling the production of synthetic fuels\, chemicals\, and commodities from fossil fuels underpinning various power-to-X scenarios. A central factor governing SOC performance is the reaction kinetics at the electrodes. Traditionally\, advances in SOC electrode performance have been pursued through modifications of electrode composition\, tailoring the bulk chemistry to enhance catalytic activity and transport properties. However\, recent developments have shown that significant improvements can also be achieved by tuning surface exchange kinetics through alternative mechanisms. In this talk\, we examine two emerging approaches: modifying surface chemistry via controlled changes in Smith acidity\, and exploiting ultraviolet illumination to drive favourable alterations to surface exchange behaviour. Together\, these strategies open relatively unexplored avenues for achieving high-performance electrodes. \nThe second part of the seminar turns to broader materials-supply challenges for next-generation energy devices. As technologies such as SOCs move toward large-scale deployment\, the identification of potential raw material constraints must be identified early in the materials and device design. At the same time\, materials in early commercialisation stages require carefully designed end-of-life strategies to prevent the emergence of difficult-to-manage waste streams. Niobium oxide-based materials have recently emerged as high-power\, durable battery anodes\, and are now in the early stages of commercialisation. Yet their refractory nature\, combined with the wide range of dopant chemistries employed\, presents substantial challenges for future recycling efforts. In this work\, we demonstrate a route to address this challenge through an aqueous-based recycling process that relies only on inexpensive\, widely available reagents\, offering a feasible path toward sustainable end-of-life management for niobium-based energy materials. \n  \nContact: Clément Nicollet (ST2E) URL:https://www.cnrs-imn.fr/en/event/george-harrington-seminar/ ATTACH;FMTTYPE=image/jpeg:https://www.cnrs-imn.fr/wp-content/uploads/2026/03/George_Harrington.jpg END:VEVENT BEGIN:VEVENT DTSTART;TZID=Europe/Paris:20260312T133000 DTEND;TZID=Europe/Paris:20260312T150000 DTSTAMP:20260409T230443 CREATED:20260324T152649Z LAST-MODIFIED:20260324T152649Z UID:3769-1773322200-1773327600@www.cnrs-imn.fr SUMMARY:Jeudis de la Chimie du Solide seminar - Yann Le Godec (IMPMC Paris) DESCRIPTION:Thursday\, March 12 at 1:30 p.m. by videoconference\n \nYann Le Godec \nInstitute of Mineralogy\, Physics of Materials and Cosmochemistry (IMPMC Paris) \n\nSynthesis under extreme conditions of new lightweight materials with remarkable properties\n  \nSummary: Modern high-pressure chemistry is today a vast and dynamic field of research\, offering promising prospects for the development of new materials of industrial interest. Although this discipline is still relatively young compared with conventional chemistry\, it is already revealing exceptional potential that remains largely unexplored. Its pioneering nature and revolutionary prospects make it a veritable scientific terra incognita\, justifying the growing interest it is arousing. \nIn this context\, recent advances in X-ray diffraction under extreme conditions have revolutionized the methods used to explore these new territories\, paving the way for unprecedented discoveries. Over the past decade\, intensive use of in situ synchrotron radiation has enabled direct observation of the synthesis pathways of new materials\, whether stable or metastable\, under extreme conditions. These materials\, often inaccessible by conventional methods\, feature remarkable properties such as high-temperature superconductivity\, exceptional hardness and optimized photovoltaics. \nIn-situ observation of synthesis processes now enables much more precise determination of the thermodynamic conditions required to access metastable states. In this presentation\, I will show that combining very high pressures and temperatures with in situ X-ray diffraction probes using synchrotron radiation is an essential methodological key to controlling the composition and microstructure (nanostructuring) of new materials (borides\, carbides\, silicon compounds\, etc.) with exceptional properties. URL:https://www.cnrs-imn.fr/en/event/jeudis-de-la-chimie-du-solide-seminar-yann-le-godec-impmc-paris/ ATTACH;FMTTYPE=image/jpeg:https://www.cnrs-imn.fr/wp-content/uploads/2026/02/yann_legodec.jpg END:VEVENT BEGIN:VEVENT DTSTART;TZID=Europe/Paris:20260408T100000 DTEND;TZID=Europe/Paris:20260408T100000 DTSTAMP:20260409T230443 CREATED:20260225T094147Z LAST-MODIFIED:20260409T085710Z UID:3622-1775642400-1775642400@www.cnrs-imn.fr SUMMARY:Tojo RASOANARIVO (PCM) thesis defense DESCRIPTION:Wednesday\, April 8 at 10:00 a.m.\n \n\nMultiscale modeling of GaN atomic layer etching in chlorinated plasmas\nSummary: Gallium nitride (GaN) is a key material for power electronics devices operating in the radio frequency domain. The miniaturization of architectures makes nanometric control of etching critical. Conventional etching processes using continuous cold plasmas in chlorinated chemistries offer high speeds\, but can induce defects in the material\, impacting device performance and reliability. Atomic layer etching (ALE)\, a cyclic process alternating chemical surface modification and activation by low-energy ion bombardment\, aims to control etching at the atomic scale while improving surface finish. This thesis focuses on the development of a multiscale model of GaN FTA in Cl₂/Ar plasmas. The simulator couples a dynamic global model describing plasma species fluxes and densities with a Monte-Carlo sheath model providing ion energy and angular distribution functions. The results of these first two models are then exploited by a kinetic Monte-Carlo surface model to describe chlorine-induced modification reactions and ion bombardment selectivity at the GaN surface during the ALE process. This surface model is fed by an ab initio study describing Cl-GaN(0001) interactions. Ultimately\, the simulator package makes it possible to link mesoscopic parameters to plasma/surface interactions at the atomic scale\, to gain a deeper understanding of the mechanisms involved and optimize process performance\, such as post-etch GaN surface finish and control of etched thickness per cycle. Ultimately\, this work can be integrated into a digital twin of GaN ALE processes\, to guide the optimization and industrialization of atomic-scale etching. \nKeywords: semiconductor\, cold plasma process\, etching\, modeling\, multiscale \n\nMultiscale modelling of Atomic Layer Etching of GaN in chlorinated plasmas\nAbstract: Gallium nitride (GaN) is a key material for power electronics devices operating in radiofrequency ranges. The downscaling of architectures makes nanometric control of etching critical. Conventional etching processes using continuous plasmas in chlorinated chemistries offer high etch rates but can induce defects in the material\, degrading device performance and reliability. Atomic layer etching (ALE)\, a cyclic process alternating between chemical surface modification and activation by low-energy ion bombardment\, aims to control etching at the atomic scale while improving the surface state. This thesis focuses on the development of a multiscale model for ALE of GaN in Cl₂/Ar plasmas. The simulator combines a global dynamic model describing plasma species fluxes and densities with a Monte Carlo sheath model providing ions energy and angular distribution functions. The results from these first two models are then used as inputs for a kinetic Monte Carlo surface model to describe chlorine-induced modification reactions and ion bombardment selectivity on the GaN surface during ALE processing. This surface model relies on ab initio study describing Cl-GaN(0001) interactions. The simulator associates mesoscopic parameters to plasma/surface interactions at the atomic scale in order to deepen understanding of the involved mechanisms and optimize process performances\, such as the GaN surface state after etching and etched thickness per cycle. Ultimately\, this work can be integrated into a digital twin for GaN ALE processes to guide the optimization and industrialization of atomic-scale etching. \nKeywords: semiconductor\, low temperature plasma process\, etching\, modelling\, multiscale URL:https://www.cnrs-imn.fr/en/event/tojo-rasoanarivo-pcm-thesis-defense/ LOCATION:Amphi IMN ATTACH;FMTTYPE=image/jpeg:https://www.cnrs-imn.fr/wp-content/uploads/2026/02/rasoanarivo_tojo.jpg END:VEVENT BEGIN:VEVENT DTSTART;TZID=Europe/Paris:20260409T090000 DTEND;TZID=Europe/Paris:20260410T170000 DTSTAMP:20260409T230443 CREATED:20260304T083908Z LAST-MODIFIED:20260304T083908Z UID:3433-1775725200-1775840400@www.cnrs-imn.fr SUMMARY:Journées des Doctorants - JDD 2026 DESCRIPTION: URL:https://www.cnrs-imn.fr/en/event/journees-des-doctorants-jdd-2026/ END:VEVENT BEGIN:VEVENT DTSTART;TZID=Europe/Paris:20260409T133000 DTEND;TZID=Europe/Paris:20260409T144500 DTSTAMP:20260409T230443 CREATED:20260326T152248Z LAST-MODIFIED:20260326T152248Z UID:3393-1775741400-1775745900@www.cnrs-imn.fr SUMMARY:Christophe VALLEE seminar DESCRIPTION:Thursday\, April 9 at 1:30 pm – Amphi IMN \n \nChristophe VALLEE \nUniversity at Albany\, CNSE\, USA \n  \nMore than 50 years of plasma etching innovation: from RIE to ALE… and what’s next?\n  \nAbstract \nIn 1974\, in their paper entitled “RF sputter-etching by fluoro-hloro-hydrocarbon gases”\, N. Hosokawa et al. proposed to combine energetic ions with volatile products for plasma etching [1]. They came up with the idea of replacing argon with fluoro-chloro-hydrocarbon gases in rf diode sputtering equipment. They observed very high sputter-etching speeds\, 10 to 20 times higher than those normally encountered with Si or Al. This marked the beginning of plasma etching combining ions and radicals\, Reactive Ion Etching (RIE). \nWith this presentation I will discuss the following 50 years of work that followed the pioneer work of Hosokawa et al\, in understanding\, designing and optimizing plasma etching processes and reactors. I will show how plasma etching was modified to enable the transistor scaling areas: geometrical scaling (1975-2002)\, equivalent scaling (2003-2024)\, and 3D power scaling with transition to complete vertical structures (2025-…). The first scaling area saw the emergence of new reactors enabling the decoupling of flow and energy. The second was accomplished thanks to the transition from continuous flow processes to pulsed processes (pulsed plasma etching\, Atomic Layer Etching). As we enter the third scaling area\, selectivity will become predominant and temperature control will be a key parameter for the plasma etching processes\, as illustrated by the recent development of cryogenic etching. Finally\, future challenges for etching processes to meet sustainability and environmental concerns will also be addressed. \nHaving completed my thesis at IMN\, I will take a little time at the beginning of my presentation to explain my career path since my thesis and what my current research activity is at CNSE. URL:https://www.cnrs-imn.fr/en/event/christophe-vallee-seminar/ ATTACH;FMTTYPE=image/jpeg:https://www.cnrs-imn.fr/wp-content/uploads/2026/03/Christophe_Vallee-e1775722452273.jpg END:VEVENT BEGIN:VEVENT DTSTART;TZID=Europe/Paris:20260409T133000 DTEND;TZID=Europe/Paris:20260409T150000 DTSTAMP:20260409T230443 CREATED:20260225T085537Z LAST-MODIFIED:20260409T125504Z UID:3629-1775741400-1775746800@www.cnrs-imn.fr SUMMARY:Jeudis de la Chimie du Solide seminar - Julien Varignon (CRISMAT Caen) DESCRIPTION:Thursday\, April 9 at 1:30 p.m. by videoconference\n \nJulien Varignon \nCRISMAT Laboratory\, CNRS UMR 6508\, ENSICAEN\, Normandie University \n\nCharge and orbital orders drive superconductivity in complex oxides\n  \nAbstract: Superconductivity\, characterized by zero electrical resistance and expulsion of the magnetic field\, remains limited by relatively modest critical temperatures Tc\, reaching 135 K at best in cuprates at ambient pressure. In complex oxides\, understanding the mechanisms by which Tc can be increased is a major challenge\, particularly from the point of view of electronic and structural chemistry. \nOxides derived from Ruddlesden-Popper An+1BnO3n+1-type phases play a central role in this issue. In these systems\, superconductivity frequently appears close to a transition between an insulating and a metallic phase. This transition is often associated with the disappearance of electronic orders such as charge orders (cationic dismutation) or orbitals\, frequently linked to Jahn-Teller-type structural instabilities. \nIn this seminar\, I show\, using first-principles simulations based on density functional theory (DFT)\, that superconductivity emerges systematically in the vicinity of these ordered phases. Even if these orders disappear in the metallic phase\, their fluctuations persist and generate sufficient electron-phonon coupling to initiate superconductivity. \nThese results thus suggest that ordered insulating and superconducting phases share a common origin1\,2. Finally\, I highlight that structural distortions of O₆ octahedral lattices\, such as rotations\, allow modulation of this electron-phonon coupling. This paves the way for an oxide structural engineering strategy to optimize Tc. \n______________________ \n1. J. Varignon\, M. Bibes\, and A. Zunger\, Nat. Comm. 10\, 1658 (2019)\n2. A. A. Carrasco-Alvarez\, S. Petit\, W. Prellier\, M. Bibes\, and J. Varignon\, Nat. Comm. 16\, 1458 (2025) \n  \nhttps://univ-nantes-fr.zoom.us/j/88146334543?pwd=8GL4UQasDKOmY9g5XmabSbPm0nDZx7.1\nMeeting ID: 881 4633 4543\nSecret code: 468276 URL:https://www.cnrs-imn.fr/en/event/jeudis-de-la-chimie-du-solide-seminar-julien-varignon-crismat-caen/ LOCATION:Videoconferencing ATTACH;FMTTYPE=image/jpeg:https://www.cnrs-imn.fr/wp-content/uploads/2026/02/Julien_Varignon-e1775722631458.jpg END:VEVENT END:VCALENDAR