Chronoamperometric Cu(II) Analysis at Gold Ultramicroelectrodes in Concentrated Sulfuric Acid Solutions

Abstract

Chronoamperometric analysis of Cu (II) ion concentration at a gold ultramicroelectrode (UME) is reported. An appropriate potential/time program was selected after the analysis of the corresponding j vs t transients in order to establish a defined value in the limiting current for analytical purposes. Good linearity between Cu (II) concentration and the stationary stripping current was obtained in the concentration of 5 g dm -3 to 150 g dm -3 range. Moreover, interference effects from sulfuric acid in a wide concentration range and from additives such as thiourea and glue showed that they do not affect the linearity between the stationary current values and Cu(II) concentration. These results could be adapted for the chronoamperometric detection of Cu(II) in on-line measurements in industrial copper refining electrolytes.

The Electro-Deposition/Dissolution of CuSO4 Aqueous Electrolyte Investigated by In Situ Soft X-ray Absorption Spectroscopy

“…Thus, the anodic peak in the inverse scan is associated with the stripping process of the deposited copper. The charge related to the copper electrodeposition is higher than that corresponding to the electro-oxidation process . This behavior can be attributed to the participation of a competing reduction process of H 2 O or H + during the electrodeposition to molecular hydrogen, the HER.…”

“…The charge related to the copper electrodeposition is higher than that corresponding to the electro-oxidation process. 27 This behavior can be attributed to the participation of a competing reduction process of H 2 O or H + during the electrodeposition to molecular hydrogen, the HER. A portion of the generated hydrogen diffuses away from the electrode interface and hence the charge is missing during the anodic scan.…”

Prospects of Application of Ultramicroelectrode Ensembles for Voltammetric Determination of Compounds with Close Standard Electrode Potentials and Different Diffusion Coefficients

“…The stationary response itself is interesting due to the fact that the current in this mode is a function of the potential, and the time dependence obtained in the experiment can be considered as parametric. As a result, sensors that are extremely convenient in chronoamperometry can be fabricated on the basis of ultramicroelectrodes [14]. Despite the high current density, due to the small area, a single ultramicroelectrode has a rather low total current, which led to the beginning of an active study of ultramicroelectrode arrays, often made in the form of small sensors.…”

An Estimate of a Frequency Characterizing the Electrochemical Stability of a Gold Electrode Modified by MHDA Thiol in Different Ways

“…They provide the characteristics related to transport as well as thermodynamic phenomena. [10][11][12][13][14][15][16][17][18] EIS is one of the most powerful technique used to study interfaces, [18] based on the analysis of the impedance of the equivalent electrical circuit, it allows the quantification of the interfaces obtained by modification of the electrodes either spontaneously when they are immersed in electrolytes, or by electrodeposition, depending on the nature and the purpose of the work performed. Some of our recent works show the quantification of gold electrodes modified by different types of thiols.…”