Registration Number
0223U005264,
0123U102729
, R & D reports
Title
Phase behaviour of ionic liquids in a disordered confinement
popup.stage_title
Head
Patsahan Oksana V., Доктор фізико-математичних наук
Registration Date
19-12-2023
Organization
Institute of Condensed Matter Physics of the National Academy of Sciences of Ukraine
popup.description2
The purpose of this research work is the development of the theory of phase transitions of ionic liquids with complex molecular structures under conditions of disordered spatial confinement. To achieve this goal, during this stage, calculations of the gas-liquid phase diagrams for a model of an ionic liquid adsorbed in a porous medium formed by a matrix of immobile randomly located particles have been conducted using analytical expressions for pressure and chemical potential conjugate to the order parameter. The model of the ionic liquid consists of a mixture of spherical anions and nonspherical cations represented by homo- and heteronuclear positively charged dimers immersed in a structureless dielectric medium. This model is characterized by such parameters as the ratio of sizes between charged and uncharged monomers of the cation, geometric porosity of the matrix, and size of the matrix particles. As a result of the conducted research, the following conclusions have been drawn: (i) a decrease in geometric porosity leads to a shift in gas-liquid phase diagrams towards lower temperatures and lower densities of ions as well as to a narrowing of the region of phase coexistence; (ii) at a fixed porosity, the critical temperature and critical density of ions decrease, while the critical volume fraction of ions increases with an increase in the size of the uncharged monomer of the cation; (iii) an increase in the size of the uncharged monomer of the cation leads to a decrease in both the critical temperature and critical density, and the disordered porous medium enhances these tendencies; (iv) increasing the size of the matrix particles at a fixed porosity results in a shift of the phase diagram towards higher temperatures and densities, consequently increasing the critical temperature, critical density, and critical volume fraction of ions.
Product Description
popup.authors
Hvozd Taras V.
Holovko Myroslav F.
Kalyuzhnyi Yurii V
Kukarkin Nazar B.
Patsahan Taras M.
popup.nrat_date
2023-12-19
