Elimination voltammetry as a powerful tool for the study of electrodeposition of metals

• Authors: ROZIK Roland; ZERZÁNKOVÁ Lenka; MIKELOVÁ Radka; TRNKOVÁ Libuše
• Year of publication: 2006
• Type: Article in Proceedings
• Conference: 57th Annual Meeting of the International Society of Electrochemistry
• MU Faculty or unit: Faculty of Science
• Field: Electrochemistry
• Keywords: Electrochemistry; Nickel; Cobalt; Copper; Paraffin impregnated graphite electrode; Elimination voltammetry with linear scan
• Description: Electrode reaction mechanisms of electrolytical coating by metals of paraffin impregnated graphite electrode (PIGE) were investigated by voltamperometric methods including the elimination voltammetry with linear scan (EVLS). The EVLS is based on the fact that the total voltammetric current (LSV) response consists of a set of particular currents, e.g. charging, diffusion, and kinetic currents having different dependences on scan rate. From voltammetric currents measured at different scan rates the elimination procedure enables selected current components to be eliminated, some current components to be conserved and unknown processes to be revealed [1-3]. In aqueous acidic solutions one of these processes is the hydrogen evolution [3,4]. The attention was focused on the interpretation of electrochemical behavior of metals (Cd, Ni, Co, and Cu) from chloride and sulphate electrolytes. Experiments were performed using the AUTOLAB potentiostat (EcoChemie) with three-electrode setting. For the calculation of elimination functions three voltammetric curves at different scan rates were recorded under the same experimental conditions (potential step and range) [5]. The differences in mechanisms of metals deposition from various supporting electrolytes have been observed as a function of metal concentrations, pH, scan rate, and electrode surface roughness. The EVLS helped also to identify the charge carrying species of metals, and the effect of electrode surface roughness. During the deposition processes the EVLS (E4 function) revealed the pre-peak (Ipp) reflecting some kinetically controlled surface reactions (e.g. adsorption, surface diffusion, nucleation). The study showed that the EVLS is suitable and powerful tool for the study of reduction processes of metals not only on mercury electrodes but also on solid electrodes.

Related projects

• Interactions among the chemicals, environment and biological systems and their consequences on the global, regional and local scales (INCHEMBIOL)
• New approaches in electrochemical analysis of nucleic acids and oligonucleotides aimed at a ultrasensitive microdetection of DNA and DNA hybridization
• Centre of Biophysical Chemistry, Bioelectrochemistry and Bioanalysis. New Tools for Genomics, Proteomics and Biomedicine