Chemistry - a European Journal vol:17 issue:18 pages:5054-5059
New metal-containing ionic liquids [Cu(CH3CN)n][Tf2N] (n = 2, 4; Tf2N = bis(trifluoromethylsulfonyl)amide) have been synthesised and used as a non-aqueous electrolyte for the electrodeposition of copper at current densities greater than 25 Adm(-2). The tetrahedral copper(I)-containing cation in [Cu(CH3CN)(4)] [Tf2N] is structurally analogous to quaternary ammonium and phosphonium ionic liquids and overcomes problems of metal solubility and mass transport. Two CH3CN ligands are removed at elevated temperatures to give [Cu(CH3CN)(2)] [Tf2N], which can be used as a concentrated non-aqueous electrolyte. The structural and electrochemical characterisation of these compounds is described herein.