Ion interactions in ionic liquids
File(s)
Author(s)
Koutsoukos, Spyridon
Type
Thesis
Abstract
Ionic liquids are being intensively investigated as more sustainable chemicals for many applications
due to their advantageous physicochemical properties. The main reason for this interest
is the synthetic flexibility associated with them, as there is a never-ending number of different
possible combinations of anions and cations, which can lead to compounds with very distinct
properties. However, the research interest has progressed fast into developing ionic liquids for
specific applications, while we are still lacking fundamental knowledge on the interactions taking
place inside of them. As a result of this, many models fail to provide accurate predictions
about the properties or reactivity of ionic liquids. This thesis presents fundamental research
on the structure-property relationships of ionic liquids, emphasising on aspects like the effects
of specific functional groups or symmetry on their physical properties. Furthermore, Electron
Paramagnetic Resonance spectroscopy is introduced as a versatile tool for characterising the
chemical environment inside of an ionic liquid. Using nitroxide spin probes as ‘spies’, we are
trying to identify the relationship between the bulk properties (e.g. viscosity) and the interactions
the radicals feel in their immediate environment. The results indicate that depending on
the examined ionic liquid and the used spin probe there is a plethora of microscale interactions
which are in no way deduced from the physicochemical studies of bulk properties.
due to their advantageous physicochemical properties. The main reason for this interest
is the synthetic flexibility associated with them, as there is a never-ending number of different
possible combinations of anions and cations, which can lead to compounds with very distinct
properties. However, the research interest has progressed fast into developing ionic liquids for
specific applications, while we are still lacking fundamental knowledge on the interactions taking
place inside of them. As a result of this, many models fail to provide accurate predictions
about the properties or reactivity of ionic liquids. This thesis presents fundamental research
on the structure-property relationships of ionic liquids, emphasising on aspects like the effects
of specific functional groups or symmetry on their physical properties. Furthermore, Electron
Paramagnetic Resonance spectroscopy is introduced as a versatile tool for characterising the
chemical environment inside of an ionic liquid. Using nitroxide spin probes as ‘spies’, we are
trying to identify the relationship between the bulk properties (e.g. viscosity) and the interactions
the radicals feel in their immediate environment. The results indicate that depending on
the examined ionic liquid and the used spin probe there is a plethora of microscale interactions
which are in no way deduced from the physicochemical studies of bulk properties.
Version
Open Access
Date Issued
2022-03
Date Awarded
2022-07
Copyright Statement
Creative Commons Attribution NonCommercial Licence
License URL
Advisor
Welton, Thomas
Roessler, Maxie
Publisher Department
Chemistry
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)