Portail HAL ENSCP
Not a member yet
9647 research outputs found
Sort by
Highly conductive ester-based solid electrolyte exhibiting remarkable stability for safe, sustainable, and high-performance lithium metal batteries
No full textInternational audienceSince the 1970s, polymer electrolytes (PEs) such as poly(ethylene oxide) (PEO) have been extensively studied to address the instability and safety issues associated with lithium metal electrodes. However, these conventional PEs suffer from low lithium transference numbers and narrow electrochemical stability windows. In this work, we introduce innovative solid-state PEs based on crosslinked poly(butyl malonate) (CPBM) and lithium salts. Unlike traditional PEO-based PEs, CPBM-based PEs are fully amorphous and self-standing, offering a suite of superior electrochemical properties. Notably, they exhibit comparable ionic conductivities to PEO-based PEs but achieve significantly higher lithium transference numbers and an impressive limiting current density enabling efficient ion transport. Another remarkable feature of our CPBM-based PEs is their wide electrochemical stability window, extending up to 4.7 V vs. Li/Li+, and an excellent stability with lithium metal. These substantial improvements in electrochemical stability have been rigorously validated through long-term cycling stability tests, including Li stripping/plating and full cells with LiFePO4 (LFP) and Mn-rich LiMn0.6Fe0.4PO4 (LMFP) electrodes. We firmly believe that polymalonate-based PEs represent a pioneering solution to overcome the limitations inherent in PEO-based PEs and pave a way to safe, high-performance lithium metal batteries, marking a significant leap forward in battery technology
Dry electrode architecture design to push energy density limits at the cell level
No full textInternational audienceHigh-energy lithium batteries require electrode architectures that enable high areal capacity, high active material content, and stable high-voltage operation—requirements that conventional slurry-based electrodes struggle to meet due to inefficient electron percolation, parasitic reactions, and limited processing-architecture predictability. Here we design and validate a dry-processed electrode architecture that leverages molecular-level coupling between fibrous carbon and binder to promote efficient electronic conduction while suppressing high-voltage interfacial degradation. This architecture achieves areal loadings >5 mAh cm−2 with >99 wt% active material and supports stable operation up to 4.70 V without compromising rate capability. The 4.55 V NMC811||graphite pouch cells retain 78% capacity after 1,000 cycles at C/3-rate, with average Coulombic efficiency exceeding 99.9%. These results are achieved without material-level modifications or specialized electrolyte additives, highlighting the potential of electrode engineering alone to unlock the intrinsic performance of active materials even under demanding conditions of high areal loading and maximum active material content
Targeted Photodynamic Therapy for Pancreatic Cancer: Recent Innovations from Fundamentals to <i>In Vivo</i> and Clinical Applications (2020-2025)
No full textInternational audiencePhotodynamic Therapy (PDT) is a clinically-approved medical modality to treat different types of localised conditions such as cancer, infections or skin conditions. Pancreatic cancer (PC) is a deadly cancer displaying a dramatic overall prognosis that has barely improved in decades as the majority of PC patients are diagnosed at a locally advanced or metastatic stage and cannot benefit of surgical resection which is the only curative treatment, the overall 5-year survival rate remains extremely low. Thus, finding new therapies for non-metastatic PC to improve local control as a bridge to surgical resection and improve survival outcomes remains a huge challenge. In this context, PDT could be an interesting option. This review will focus on the use of PDT with targeted photosensitisers or nanoparticles to treat PC in recent studies (2020-2025) from in vitro to in vivo experiments and clinical applications
Design, Synthesis, and Evaluation of Organic and Organometallic Pyrazoline Derivatives as Selective Dual COX-2/5-LOX Inhibitors and Potential Anticancer Agents
No full textInternational audienceInspired by the structure of the anti-inflammatory drug Celecoxib, which is currently used in cancer prevention and treatment, we report the design, synthesis, and biological evaluation of organic and organometallic molecular hybrids based on pyrazolines (4a–h). Structure–Activity Relationship (SAR) analyses showed that the combination of catechol-benzenesulfonamide in 4a (organic) and 4c (ferrocenyl) derivatives acts as potent and highly selective dual inhibitors (IC50 COX-2 = 4.58 and 2.88 μM; IC50 5-LOX = 0.23 and 0.10 μM, respectively; evaluated against COX-1 and 15-LOX isoforms). Molecular dynamics simulations of 4a and 4c in 5-LOX showed their preferential localization at the allosteric site and at the entry channel, respectively, consistent with their noncompetitive (4a) and mixed (4c) kinetics. Furthermore, the noncytotoxic complex 4c (MRC-5, CC50 = 38.13 μM) exhibited anticancer effects in ovarian cancer cells (A2780, CC50 = 13.79 μM) that overexpress the proinflammatory enzymes COX-2 and 5-LOX (Western Blot), exceeding the activity of the drug Celecoxib
Coarse-grained physics-based modelling for tape casting of fuel-electrode supports in Solid Oxide Cells
No full textInternational audienceOptimising the tape casting process for fabricating NiO/YSZ cermet-based fuel-electrode supports in Solid Oxide Cells remains a resource-intensive challenge. Improving the green tape properties are often reliant on trial-and-error procedures or proprietary knowledge that is inaccessible to the broader scientific community. In this work, we use computational simulations as a powerful tool to link the manufacturing process to the final microstructure of the tape. A novel three-dimensional physics-based model is presented to simulate the slip preparation and the homogeneous drying process of the tape casting producing the fuel electrode support in Solid Oxide Cells. Our model is well-calibrated to experimental data, and we investigate the dried microstructure of the simulated support
Polymer Vesicle Microreactors Produced using Permeable Polymer Blocks: Circumventing Complex Functionality to Impart Membrane Permeability
No full textInternational audienceThe use of giant vesicles as microreactors presents a novel approach to control biochemical reactions in confined spaces, offering advantages such as compartmentalization, tunable permeability, and potential for biomimetic applications. These constructs can serve as versatile platforms for catalysis, drug delivery, and synthetic biology by providing confined environments that mimic natural cellular compartments. We have successfully produced microvesicles (also referred to as giant vesicles) by means of the simple double emulsification method using five amphiphilic block copolymers comprising poly(ethylene oxide) (PEO) as hydrophilic segment and five disparate hydrophobic blocks: poly(caprolactone) (PCL), poly(methyl methacrylate) (PMMA), poly(lactic acid) (PLA), poly [2-(diisopropylamino)ethyl methacrylate] (PDPA), and poly[2-(heptamethyleneimino)ethyl methacrylate] (PHIA). The last two blocks are pH-responsive (PDPA, PHIA), while the first ones are not (PCL, PMMA, PLA). The resulting vesicles have average size ranging from 2.9 to 9.3 µm, with the pHresponsive vesicles exhibiting larger diameters, likely due to partial protonation of the hydrophobic blocks. The formation of the giant vesicles was confirmed via optical and fluorescence microscopy using Nile red as a hydrophobic marker. The ability of the vesicles to encapsulate larger molecules was demonstrated by loading Alexa-labeled bovine serum albumin (BSA-Alexa). In the step further, the potential of these vesicles as microreactors was explored by encapsulating horseradish peroxidase enzyme (HRP) and evaluating the catalytic oxidation of o-dianisidine in the presence of hydrogen peroxide (H₂O₂), a reaction catalyzed by the HRP enzyme. The experimental evidences highlight that the pH-responsive vesicles are permeable to the reactants, as evidenced by colored product formation, whereas the permeability of the nonresponsive assemblies is reported to be negligible. Truly, the non-responsive vesicles exhibited particularly low permeability, even at the pH where the catalytic activity of the enzyme is optimized. These findings highlight the potential of pH-responsive vesicles for controlled molecular transport and catalytic applications, paving the way for their use in biocatalysis as microreactors
Élaboration de films polyesters biosourcés et évaluation de leur biodégradabilité en digestion anaérobie
No full textInternational audienc
Separation and detection of hemicellulose and insights into chemical heterogeneity through capillary electrophoresis
No full textInternational audienc
Dual-Continuum Models of Lithium-Ion Batteries are Fast and Accurate Alternatives to the Doyle-Fuller-Newman Approach: I. Derivation and Validation
No full textInternational audienceOne of the main reasons for the Doyle–Fuller–Newman (DFN) model’s success in simulating lithium-ion batteries is also one of its main limitations—its hybrid micro/macro formulation. On one hand, this captures the slow diffusion of lithium within the active material particles. On the other hand, it makes the retention of realistic particle geometries computationally prohibitive, thereby provoking strongly simplifying assumptions on their shape. Dual-continuum models employ a fully macroscale description of the battery, and thus can potentially circumvent these challenges. Despite their widespread use in other fields, they have seen little application in battery modelling. In this work, we derive a dual-continuum model for lithium-ion batteries using the volume-averaging technique. A novel mapping between the volume-averaged and surface-averaged active material concentrations is introduced, based on the microscale source terms that generate concentration fluctuations. Unlike the DFN model, this approach makes no assumptions about particle shape but instead relies on a closure problem solved on the electrode microstructure. The resulting model is validated against a detailed microscale model, the DFN model, a recent dual-continuum formulation, and experimental data. Across all cases considered, our dual-continuum model reproduced cell-voltage data more accurately than the DFN approach while requiring 70–80% less computation time
Incorporation of Ruthenium Polypyridyl Complexes into DNA Oligonucleotides by Copper-Free Click Chemistry
No full textInternational audienceAlternative methods for the preparation of naïve libraries for SELEX experiments are in dire need, particularly when hydrophobic, bulky, and complex modification patterns are considered. Here, we explore first steps towards the preparation of libraries equipped with ruthenium polypyridyl complexes using Strain-Promoted Azide-Alkyne Cycloaddition (SPAAC) reactions. We demonstrated that dsDNA products can be efficiently equipped with dibenzocyclooctyne (DIBAC) moieties using a suitable modified nucleoside triphosphate and PEX reactions or PCR. The resulting dsDNA products can then be further modified using SPAAC and ruthenium polypyridyl complexes equipped with azide moieties, permitting the installation of >10 complexes. Finally, dsDNA can be efficiently converted into the corresponding modified ssDNA using magnetoseparation. These results offer the possibility of producing longer oligonucleotides equipped with complex modification patterns and open the way to SPAACclick-SELEX methodologie