Impact of speciation on the tellurium electrochemistry in choline chloride-based deep eutectic solvents

• DOI: 10.1016/j.elecom.2022.107327
• Publication Date: 2022-07-16T09:19:38Z
• Authors: Alassane Sorgho; Moussa Bougouma; Gael De Leener; Julien Vander Steen; Thomas Doneux
• Keywords: Choline chloride; Tellurium; Glassy carbon; Oxalic Acid

The electrochemistry of tellurium in two different deep eutectic solvents, choline chloride - urea (ChCl-U) and oxalic acid (ChCl-Ox) was studied on glassy carbon (GC) polycrystalline (Au(poly)) gold electrodes by cyclic hydrodynamic voltammetries. Voltammetric responses associated with the redox pairs Te(IV)/Te(0) Te(0)/Te(-II) are recorded, a striking difference between ChCl-U ChCl-Ox being observed kinetics couple, which is electrochemically reversible but highly irreversible ChCl-U. This attributed to speciation Te(IV) species DESs. UV–vis spectrophotometry 125Te NMR spectroscopy demonstrate that exists as [TeCl6]2- ChCl-Ox, point an oxo-coordinated form Accordingly, electrochemical reversibility assigned lability contrasting inertness present