Abstract
In this paper we first present the synthesis and the physicochemical properties of low hygroscopic piperidinium-based ionic liquids that allow performing electrodeposition without the need of a glove box. A deep analytical study of the electrochemical system In(III)/In(0) in a 1-butyl-1-ethylpiperidinium bis(trifluoromethylsulfonyl)imide electrolyte (BEPipTf2N) is then described. Troublesome aspects of using chloride metallic precursors in Tf2N-based electrolytes are highlighted using cyclic votammetry and stripping experiments. Indeed, voltammograms reveal a complex electrochemical behaviour and several cathodic and anodic signals that can be attributed to the formation of indium chlorocomplexes during the scan, due 2 to changes of concentrations ratio [Cl-]/[In(III)] of interfacial species during In(III) reduction reaction. In(III)/In(0) electrochemical system and metallic indium electrodeposition in a chloride-free electrolyte is then presented. The use of a chloride-free electrolyte leads to an improvement of electrodeposits morphology and to an increase in faradic yield from 33% to 85%.