PHENIX laboratory

Metal-organic framework (MOF)/polymer composites have been widely investigated in the past decade for gas separation applications. However, the impact of the MOF nanoparticle morphology and size in gas separation has not yet been systematically studied by computer simulation techniques. In this work, coarse-grained simulations are deployed to study gas adsorption in ZIF-8/PVDF at the nanoparticle level as a test case. ZIF-8 nanoparticles of different morphologies and sizes are explored, and single-gas adsorption of CO2, N2, and CH4 is investigated throughout the extension of the bulk and surface of the nanoparticle as well as of the polymer phase. The adsorption sites of all guest molecules in bulk ZIF-8 are reproduced with remarkable accuracy, despite the reduction of degrees of freedom. The expected preference for CO2 over the other two gases is also captured. Nanoparticles of smaller sizes provide a better separation performance under ambient conditions, while rhombic dodecahedron nanoparticles perform better than cubic ones. This work presents a perspective on the merits and limitations of modeling gas adsorption in MOF/polymer composites at the nanoparticle level via particle-based coarse graining approaches and provides a methodological setup which can be integrated into high-throughput schemes, bringing us closer to reaching time- and length scales that can be directly compared with experimental data.

The original version of this Article contains errors in Table 1, where the values of the surface anisotropy constant Ks (J/m 2 ) are incorrectly stated as 10 5 J/m 2 for the Samples S1, S2 and S3, respectively.The correct and incorrect values appear below.

Liquid battery electrolytes based on mixtures of salts with weakly and strongly associating anions have emerged as a promising route toward high-performance, sustainable battery technologies. Their success is primarily attributed to the unique influence of salt composition on the solvation structure. Here, we employ classical molecular dynamics simulations, corroborated by experimental data, to study mixed lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) / lithium nitrate (LiNO3) in diglyme electrolytes, a formulation of particular interest for lithium–sulfur and lithium-oxygen batteries. We investigate how the ratio of weakly associating anions (TFSI–) to strongly associating anions (NO3–) affects ion transport within the electrolyte. Our findings reveal that the anion ratio significantly impacts both the solvation structure and the solvation dynamics, which together contribute to the distinct transport behavior observed in these systems. These findings underscore the tunability of battery electrolyte transport properties through careful mixing of anions.

Abstract Separation is a crucial step in the analysis of living microparticles. In particular, the selective microseparation of phytoplankton by size and shape remains an open problem, even though these criteria are essential for their gender and/or species identification. However, microseparation devices necessitate physical membranes which complicate their fabrication, reduce the sample flow rate and can cause unwanted particle clogging. Recent advances in microfabrication such as High Precision Capillary Printing allow to rapidly build electrode patterns over wide areas. In this study, we introduce a new concept of membrane-less dielectrophoretic (DEP) microseparation suitable for large scale microfabrication processes. The proposed design involves two pairs of interdigitated electrodes at the top and the bottom of a microfluidic channel. We use finite-element calculations to analyse how the DEP force field throughout the channel, as well as the resulting trajectories of particles depend on the geometry of the system, on the physical properties of the particles and suspending medium and on the imposed voltage and flow rates. We numerically show that in the negative DEP regime, particles are focused in the channel mid-planes and that virtual pillars array leads either to their trapping at specific stagnation points, or to their focusing along specific lines, depending on their DEP mobility. Simulations allow to understand how particles can be captured and to quantify the particle separation conditions by introducing a critical DEP mobility. We further illustrate the principle of membrane-less DEP microseparation using the proposed setup, by considering the separation of a binary mixture of polystyrene particles with different diameters, and validate it experimentally.

Biological and robotic systems often operate in confined environments where material must be gathered without centralized control. Inspired by the effective collection strategies of aquatic worms (Lumbriculus variegatus and Tubifex tubifex), we investigate how active filaments autonomously aggregate dispersed particles. We study this process across four platforms: living worms, a robotic chain, Brownian dynamics simulations of active polymers, and a coarse-grained toy model. We show that aggregation emerges from repeated contact and body deformation, and demonstrate that clustering dynamics are governed by filament length and bending stiffness. Across systems, particle gathering follows a shared aggregation-fragmentation process, with the steady-state average cluster size scaling as $\langle s\rangle_L\sim W/D^2$, where W is the effective width of the path cleared by the filament and D the domain size. We find that filament flexibility modulates W, enabling more flexible filaments to sweep larger areas and collect more particles. These results establish a unifying framework for understanding how shape and flexibility influence transport and organization in active filament systems and filamentous robots.

International audience

Protic ionic liquids, PILs, are promising materials for energy storage applications, in part due to their ability to decouple proton transport from ion diffusion. In this work, the proton transfer mechanism in 1-ethylimidazolium bis(trifluoromethanesulfonyl)imide ([HEIM][TFSI]) IL was studied by means of three different computational approaches. Classical polarizable molecular dynamics simulations were used to explore the structure and dynamics of the fully ionized system, while Density Functional Theory calculations were carried out to estimate the energy barriers for the different proton transfer reactions. Finally, the proton transfer was explicitly studied by means of Neural Network Force Field simulations. Our results show that this reaction is indeed possible when doping the IL with an excess of deprotonated cations, and highlight the importance of the formation of dimers between donor and acceptor species for the proton transfer to occur. The main driving factor for the reaction was found to be the energy cost for reaching a suitable coordination environment and form such dimers, which is higher than that for the transfer reaction.

Most breast cancers can be curable at an early stage with locoregional treatments, and the main therapeutic weapons in recurrence or metastatic situations are targeted therapies. In this context, the recent emergence of the glycoprotein TROP2 (trophoblast cell surface antigen 2) as a promising therapeutic target has led to therapeutic paradigms for treating patients with advanced or metastatic breast cancer. Here, we propose to develop, using a solid phase imprinting approach, fluorescent molecularly imprinted polymer nanoparticles containing the imprint of TROP2 epitopes acting as a key-hole system. These nanoparticles are small, spherical, very stable, and possess strong fluorescence. In vitro analyses using flow cytometry and confocal microscopy show that these nanoparticles are specifically bound to TROP2-overexpressing breast cancer cells. Furthermore, cell viability was performed to validate their cellular nontoxicity and biocompatibility. In addition, these nanoparticles efficiently penetrated 2D cultures and 3D spheroid breast cancer cell cultures. Overall, we have generated nontoxic MIP that specifically targeted TROP-2 overexpressed human breast cancer.

This paper presents a novel approach for the sensitive detection of Cu(ii) ions in acidic industrial samples, used in the manufacture of printed circuits.