Electrochemical formation and stability of copper selenide thin films in the choline chloride-urea deep eutectic solvent at gold electrode. (20th August 2022)

• Record Type: Journal Article
• Authors: Sorgho, Alassane; Mernissi Cherigui, El Amine; Bougouma, Moussa; Aldibaja, Fadi Kamal; Nisol, Bernard; Reniers, François; Buess-Herman, Claudine; Doneux, Thomas
• Is Part Of: Electrochimica acta. Volume 424(2022)
• Publication Date: 2022-08-20
• Subjects: Copper selenide (Cu2Se) -- Electrodeposition -- Deep eutectic solvent -- Cyclic voltammetry; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2022.140676
• Languages: English
• ISSNs: 0013-4686

Abstract

Abstract: The electrodeposition of copper-selenium binary compounds on gold electrode was investigated in the choline chloride – urea (ChCl-U) deep eutectic solvent at 110 °C. Cyclic voltammetry and potentiostatic deposition followed by stripping voltammetries were employed to gain thermodynamic insights pointing to the formation of Cu2 Se, which is supported by X-Ray Photoelectron Spectroscopy. The electrochemical stability domain of the compound is about 900 mV (from ≈−0.81 V to ≈+0.07 V vs. a silver quasi-reference electrode) and is consistent with the thermodynamics of induced co-deposition. The domain is limited at positive potentials by the oxidation to Se(0) and at negative potentials by the reduction to Cu(0). While copper is readily deposited on the gold electrode, the electrodeposition of selenium requires a significant overpotential. As a consequence, copper is kinetically favoured in the co-deposition and is present in its pure form at short deposition times. This is circumvented by using longer deposition times or more negative potentials. Photoelectrochemical measurements show that the as-deposited compound behaves as a p-type semiconductor.