Applied Chemical Engineering

NMR study of nitrate ionic liquids confined between micrometer-spaced plates

Andrei Filippov

Luleå University of Technology

http://orcid.org/0000-0002-6810-1882

Oleg I Gnezdilov

Kazan Federal University

Maiia Rudakova

Luleå University of Technology

Rustam Gimatdinov

Kazan State Medical University

Victor P. Arkhipov

Kazan National Research Technological University

Oleg N. Antzutkin

Luleå University of Technology

DOI: https://doi.org/10.59429/ace.v7i2.5462

Keywords: diffusivity; ion dynamics; phase transformation; confined ionic liquid

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Abstract

This review paper presents the results of a study conducted using nuclear magnetic resonance (NMR) methods to investigate the dynamic behaviour of ionic liquid-based compositions in micrometre-spaced confinement. Ethylammonium nitrate (EAN) and other ionic liquid (IL) systems with nitrate anion in glass or quartz spaced confinement demonstrate anomalous cation dynamics that differ from those observed in bulk and in nano-confinement. It was demonstrated that the principal axis of the nitrate anion exhibits preferential orientation to the surface, akin to that in liquid crystals. It was shown that the cation translational mobility reversibly changes during exposure to a static magnetic field. This phenomenon was interpreted as a result of intermolecular structure transformations occurring in the confined ILs. The mechanisms of these transformations were discussed.

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