The neutron spin-echo measurements on IN11

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Table of contents

Introduction
Why this thesis?
Ionic Liquids: a safe electrolyte, but not efficient enough
A promising route for better conductivity: nanometric confinement
Dimensionality: confinement of a molecular liquid in a solid matrix: from
powders to nano-pipes
1 Ionic liquids in the bulk state
1.1 Historical hints
1.2 Self-organization at the mesoscale
1.2.1 State of the art
1.2.1.1 Ions ordering
1.2.1.2 Self-organisation at the mesoscale
1.2.2 Self-organization: a SANS analysis
1.3 Dynamical properties of bulk ILs probed by QENS measurements
1.3.1 State of the art
1.3.1.1 ILs dynamic at the molecular scale
1.3.1.2 Ion diffusion at the microscopic scale
1.3.2 Experimental part
1.3.2.1 Choice of experimental techniques
1.3.2.2 The measurements
1.3.2.2.1 The Time of Flight experiments on IN5
1.3.2.2.2 The Time of Flight experiments on LET
1.3.2.2.3 The Backscattering measurements on IRIS
1.3.2.2.4 The neutron spin-echo measurements on IN11
1.3.3 Effects of the cation-anion couple on ILs dynamics
1.3.4 Study of the cationic diffusion OMIM-BF4 at the molecular scale: a phenomenological approach
1.3.5 Characterization of the cationic dynamics at the molecular scale using a combination of QENS techniques: the case of the OMIM-BF4
1.3.5.1 Point of the departure: the dynamics at the picoseconds scale probed by ToF spectroscopy
1.3.5.2 A new multi-components model
1.3.5.2.1 Modelling of the cation diffusion: the generalised
Gaussian model
1.3.5.2.2 Modelling the molecular re-orientation
1.3.5.2.3 The total dynamical structure factor
1.3.5.3 Analysis procedure
1.3.5.4 Results and discussion
1.3.5.4.1 Re-orientation dynamics
1.3.5.4.2 Diffusion inside the aggregate
1.3.5.4.3 Long range diffusion
1.3.6 Test of model robustness with the selective deuteration: the case of the BMIM-TFSI
1.3.6.1 Re-orientation dynamics
1.3.6.2 Diffusion inside the aggregate
1.3.6.3 Long range diffusion
1.3.7 Conclusions and comparison with the previous results
2 Properties of the ionic liquids confined in anodic aluminium oxide membranes
2.1 State of the art on the ILs confinement: the ionogels
2.2 The porous anodic aluminium oxide membranes
2.2.1 The AAO synthesis
2.2.2 The AAO morphology
2.2.3 Choice and preparation of the sample
2.2.4 Check of the IL confinement by contrast variation
2.3 ILs under confinement: thermodynamical aspects
2.3.1 A brief introduction about the ILs thermodynamical properties
2.3.1.1 Bulk IL phase diagram
2.3.1.2 Confinement effects on the ILs phase transition
2.3.2 The case of the confined BMIM-TFSI: a DSC study
2.3.2.1 A double glass transition in the confined state
2.3.2.2 Crystallisation temperature
2.3.2.3 Melting point depression
2.4 Confinement effect on the IL self-organisation behaviour by WAXS
2.4.1 Introduction: Surface effects
The surface effects
2.4.2 Experimental part
2.4.3 The liquid structure factor determination
2.4.4 Phenomenological analysis
2.4.5 Conclusion
2.5 Confinement effect on the ILs dynamics at molecular level
2.5.1 Confinement effects on the ILs dynamics in the literature
2.5.2 Experimental part
2.5.3 Characterization of the confined IL dynamical behaviour
2.5.3.1 Long range diffusion
2.5.3.1.1 NSE vs BS scenarios
2.5.3.1.2 Results
2.5.3.2 Diffusion inside the aggregate
2.5.3.3 The re-orientation dynamics
2.5.4 Conclusions
2.6 The IL leaks: a NMR 1D tomography study
2.6.1 The NMR 1-D tomography
2.6.1.1 The basis of the NMR tomography
2.6.1.2 The instrument and its calibration
2.6.2 Results
3 Properties of the ionic liquids confined in carbon nanotubes membranes
3.1 Sample preparation
3.1.1 What are carbon nanotubes?
3.1.2 Experimental protocol for the CNTs membranes production
3.1.2.1 Carbon nanotubes synthesis
3.1.2.2 The membrane formation
3.1.2.3 The membrane opening
3.1.3 Membrane filling
3.2 Dynamical effect of the confinement
3.2.1 Cationic dynamics at molecular scale probed by QENS
3.2.2 Ionic conductivity probed by impedance spectroscopy
3.2.3 Ions dynamics probed by NMR spectroscopy
Conclusions and perspective
A The neutron scattering theory (from [1, 2])
A.1 Fundamental quantities in a scattering experiment
A.2 Van Hove formalism
A.3 Single particle dynamics probed by incoherent quasi-elastic scattering
A.4 Quasi-elastic neutron scattering analysis: model for the atomic motio
A.4.1 Translational motion model
A.4.1.1 Free diffusion model (Fick’s law)
A.4.1.2 Jump diffusion model
A.4.2 Rotation motion models
A.4.2.1 Jump model between two equivalent sites
A.4.2.2 Jump model between three equivalent sites
B Time of flight technique
B.1 ToF spectrometer
B.2 Direct geometry ToF spectrometer
C Neutron spin-echo spectroscopy
C.1 The spin dynamics in a magnetic field
C.2 The spin-echo principle
C.3 The transmission of a analyser
C.4 Determination of the beam polarisation from a spin-echo measure .
C.5 The case of quasi-elastic neutron scattering measure
D Ion pairs and the concept of ionicity
E ILs applications
E.1 ILs as green solvents
E.2 Energy management by electrochemical devices
Energy management by electrochemical devices
Bibliography