Nanoconfined Ionic Liquids
2.6 Conclusions
In the chapter an overview of the formation, structures, features, and applications of confined ILs with regard to corresponding bulk ILs is presented. IL confinement may be easily performed by basic physical entrapment techniques. Confined ILs form a new class of hybrid materials with combined features of ILs and matrices. As a result, the major disadvantages of bulk ILs such as high viscosity and low diffusivity become irrel- evant. Although, over recent years, significant advances have been made in nanocon- fined IL research, detailed studies on the correlation between structure, features, and behavior are still needed.
The combined use of ionic liquids and miniaturized devices for analytical chemistry is a powerful approach in the development of green analytical methodologies. However, despite the increasing interest in ionic liquids, the coupling of IL with several analytical applications has not achieved yet the popularity and the expected acceptance in scien- tific community. This fact could be caused by problems with limited wettability of several material surfaces and hence difficulties in achieving a stable film/layer of ionic liquid used in the developed method. The use of an ionic liquid with sol–gel technology,
Nanoconfined Ionic Liquids 59
named ionogels, as extraction materials or electrolytes provides an efficient way to prepare materials with high specific surface areas and mesopores loaded with ionic liquid. Ionogels can be functionalized by the incorporation of organic functions in the solid matrix, which opens up new routes for designing materials. Thus, ionogels, the preparation and shaping of which are very easy and cheap, form a new class of temperature‐resistant solid materials, applicable in sample preparation techniques such as solid‐phase microextraction, solid‐phase extraction, and stir‐bar extraction, or as an electrolyte in biosensing devices.
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