4,4-Bipyridinium ionic liquids exhibiting excellent solubility for metal salts: Potential solvents for electrodeposition

Newly synthesised 4,4-bipyridinium based ionic liquids exhibit good metal coordinating abilities and are able to dissolve metal salts at high concentrations. The ability to capture metal salts into the ionic liquid media facilitates the application of ionic liquids in many areas such as metal extraction or electrochemistry. The ionic liquid n-butyl-4,4-bipyridinium bis(trifluoromethyl)sulfonylamide ([C4Bipyr][Tf2N]) exhibits a large liquidus range and a wide electrochemical window. The successful electrodeposition of Cu (II) to Cu (0) from a solution of Cu(NO3)2 in [C4Bipyr][Tf2N] shows the potential of this new type of ionic liquids for electrodeposition.