Iuliia Voroshylova

Abstract This study investigates the structural and transport properties of SDS, CTAB, and SB3-12 micelles in three deep eutectic solvents (DESs), Ethaline, Glyceline, and Reline, using molecular dynamics (MD) simulations. The influence of solvent composition on micelle morphology, interactions, and dynamics was explored, revealing key differences driven by the DES environment. Structural analyses, including eccentricity and radius of gyration, demonstrated that micelle shape and compactness vary significantly depending on the solvent. In Ethaline and Reline, larger micelles showed significant deviations from spherical shapes, while micelles in Glyceline became more spherical and compact, particularly those formed by SB3-12. Radial distribution functions highlighted different levels of micelle-solvent interactions, with SDS showing strong interactions with HBD components and SB3-12 exhibiting prominent self-interaction. According to hydrogen bonding analysis, micelles slightly disrupt the DES hydrogen bond network, with SB3-12 establishing the most significant hydrogen bond connections. The transport property analysis revealed that larger micelles have lower diffusion coefficients, whereas smaller micelles enhance DESs' component mobility. These findings advance the understanding of micelle behavior in DESs and also help in the optimization of DES-surfactant systems for applications such as electrodeposition, nanomaterial templating, and drug delivery. Future research will focus on surfactant interactions with surfaces to further improve these applications.

Abstract An interaction between the hydrogen molecules and circumcoronenes (CCs) decorated with light transition metals, namely Sc, Ti, and V, is investigated using density functional theory and ab initio molecular dynamics. The systems under study show affinity to bind H<inf>2</inf> molecules in two distinct ways: formation of η2-coordination, also called Kubas interaction, and dissociation of H<inf>2</inf> molecule leading to so-called dihydride coordination. When considering the interaction of Sc-, Ti-, and V-decorated CCs with one H<inf>2</inf> molecule only, the dihydride coordination is energetically preferred over the Kubas interaction by 114, 73, and 74 kJ mol−1, respectively. However, when considering the interaction of Sc-, Ti-, and V-decorated CCs with a larger number of H<inf>2</inf> molecules, the energy difference between these two types of systems decreases significantly (up to 1 kJ mol−1). This finding points on the dynamic co-existence of these systems which is confirmed also by molecular dynamics simulations. The strongest H<inf>2</inf> binding is found for V-decorated CC, followed by Ti-decorated CC and Sc-decorated CC. Calculated H<inf>2</inf> binding energies of these Kubas interactions are in the interval of −40 to −80 kJ mol−1, which is suitable for H<inf>2</inf> storage applications. It is shown that Sc-, and Ti-decorated CCs are able to chemisorb four H<inf>2</inf> molecules per one metal atom while V-decorated CC is able to chemisorb only three H<inf>2</inf> molecules per one V atom. However, formed V–H bonds are significantly stronger than Ti–H and Sc–H ones. The hydrogen storage capacity of fully saturated Sc-decorated CC is sixteen H<inf>2</inf> molecules, corresponding to a gravimetric density of 4.5 wt%. © 2025 Elsevier B.V., All rights reserved.

Abstract Due to their distinctive combination of ionic liquid (IL) characteristics and magnetic susceptibility, magnetic ionic liquids (MILs) have emerged as promising materials for gas capture and separation. In this study, molecular dynamics (MD) simulations were employed to investigate the thermodynamic, transport, and structural properties of selected MILs and their interactions with environmentally relevant gases, including methane (CH4), ammonia (NH3), carbon dioxide (CO2) and sulfur dioxide (SO2). The study focused on both imidazolium-based ([C4C1im]+) and phosphonium-based ([P66614]+) cations paired with various anions, including [FeCl4]- , [FeBr4]-, [MnCl4]2- and [GdCl6]3-. Fixed-charge force field parameters were established and validated for phosphonium-based MILs for the first time in the area. Free energy calculations demonstrated that phosphoniumbased MILs with multivalent anions exhibit favorable solvation energies for CO2 and SO2 gases, indicating a high potential for selective gas capture. A reduction in gas mobility is observed in these multivalent-based MILs/gas systems. The molecular-level insights provided by radial distribution functions (RDFs) elucidate the critical role of anions in determining solvation behavior. This observation underscores the importance of these paramagnetic elements in the interactions between the gases and MILs. This study advances the understanding of gas-MIL interactions and offers a foundation for the rational design of advanced materials for industrial gas capture and environmental remediation processes.

Abstract Progress in electrochemical applications of ionic liquids builds on an understanding of electrical double layer. This computational study focuses on structure-determined quantities - maximum packing density, potentials, and capacitances - evaluated using a one-electrode electrical double layer model. Interfaces of the 40 studied ions are grouped into four distinct classes according to their characteristic packing at the model surface. The simulations suggest that the exact screening by a monolayer of counter-ions (preceding the crowding of ions) is unlikely for ions in known air- and water-stable ionic liquids within their electrochemical stability window. This work discusses how the assessed structure-determined quantities can guide the experimental tuning of (electro/mechano)chemical properties and characterize the structure of ionic liquid-electrode interfaces.

Abstract This study investigates the structural and dynamic properties of ternary mixtures composed of NaPF6, ethylene carbonate (EC), and the ionic liquid choline glycine (ChGly), with a focus on their potential as electrolytes for supercapacitors. The combination of NaPF6-EC, known for its high ionic conductivity, with the biodegradable and environmentally friendly ChGly offers a promising approach to enhancing electrolyte performance. Through molecular simulations, we analyze how the inclusion of small concentrations of ChGly affects key properties such as density, cohesive energy, and ion mobility. Our findings demonstrate that the NaPF6-EC-ChGly mixture exhibits a complex network of electrostatic interactions and hydrogen bonding, with the glycine anion significantly influencing the liquid structure. In mixtures with small additions of ChGly, we observed an optimal balance of diffusion and ionic mobility. These results highlight the potential of ChGly as a green additive to conventional electrolytes, paving the way for more sustainable and high-performance energy storage devices.