Abstract
The central concept of this project is to highlight three major ionic liquid properties. It lies on the control of the structured and structuring properties that are considered as complementary to the usual ionic liquids properties (ionic conductivity, thermal stability, electrochemical stability). However, this is a relatively small part of this work. The strong key point is the synthesis of redox ionic liquids. In this work a new biredox ionic liquids (contaning redox moieties both on the anion and the cation constituting the ionic liquid) have been successfully synthesized for the first time. This electro-activity opens the development of electrolytes for supercapacitors whose the specitific capacity is between two and five times larger than the values found in the literature. Meanwhile, redox ionic liquids have been associated with carbon nanotubes; the obtained composites were implemented as electrode materials for the study of dynamic electron transfer and ionic transfer. Besides these results, ionic liquids have been structured by supramolecular chemistry. Polymerized ionic liquids were obtained, shaped by electrospinning and tested as a solid electrolyte in a supercapacitor system. The electrochemical properties of these components (electrolyte materials or electrode materials) have been extensively studied by cyclic voltammetry, electrochemical impedance spectroscopy, galvanostatic cycling and scanning electrochemical microscopy. The results completely validate the original concept to take advantage of molecular, supramolecular and macromolecular chemistries of ionic liquids to improve electrochemical energy storage devices.