Microgravimetric Studies of Selenium Electrodeposition Onto Different Substrates

Abstract

The mechanism of selenium electrodeposition from sulfuric acid solution on different substrates was studied with the electrochemical techniques. The cyclic voltammetry was combined with the quartz crystal microbalance technique to analyze selenium deposition process. The electrochemical reduction of selenous acid on gold, silver and copper electrodes was investigated. It was found that reduction of selenous acid is a very complex process and it strongly depends from the applied substrate. The voltammetric measurements indicate the range of potentials in which the process of reduction of selenous acids on the applied substrate is possible. Additionally, the microgravimetric data confirm the deposition of selenium and they reveal the mechanism of the deposition process.Keywords: selenium, electrochemistry, electrodeposition, cyclic voltammetry, electrochemical quartz crystal microbalance Przedstawione w niniejszej pracy wyniki badań opisują mechanizm elektrochemicznego osadzania selenu z roztworów siarczanowych na różnych podłożach. W celu dokładnej analizy zachodzących procesów elektrodowych w badaniach zastosowano technikę cyklicznej woltamperometrii połączoną z elektrochemiczną mikrowagą kwarcową. W pracy porównano procesy redukcji kwasu selenowego(IV) na elektrodach złotej, srebrnej i miedzianej. Dzięki zastosowanym technikom badawczym jednoznacznie określono zakres osadzania się selenu na wybranych podłożach oraz wskazano możliwy mechanizm przebiegających reakcji elektrodowych.

The Voltammetric Analysis of Selenium Electrodeposition from H2SeO3 Solution on Gold Electrode

“…The onset potential of the voltammetric experiment was set at 0.5 V vs. Ag/AgCl electrode and was swept in the negative direction first, then reversed at -0.6 V. Subsequently, the potential was changed to the second reverse potential 1.1 V and the whole scan was finished at the initial potential 0.5 V. During the sweeping in the negative direction five reduction peaks A, B, C, D and E are observed. The nature of these peaks was analyzed in acidic environment by several groups and is described in the subsequent papers [19,20,[22][23][24][25][26][27][28]. It should be noted that common feature for all these reports is gold substrate, but of different quality (single crystal or polycrystalline) and pretreatment procedures.…”

“…The very good reports by Andrews et al [19], Stickney at al. [20][21][22][23][24], Alanyalioglu et al [25] Machado et al [26,27] and Kowalik [28] provided extensive analysis of selenium electrodeposition on gold. Nonetheless, some aspects of the voltammetry results are still not clear.…”

Electrochemical study of selenium (IV) mediated by carbon nanotubes modified glassy carbon electrode in blood medium

“…A new mechanism of selenium electrodeposition from H 2 SO 4 solution on different substrates such as gold, silver and copper electrodes was studied for reduction current peaks of selenous acid and confirms the mechanism of the deposition process [13].…”

Electrochemical, Spectroscopic, and Computational Investigations on Redox Reactions of Selenium Species on Galena Surfaces

“…To date, the geologic occurrence and distribution of Se in sulfide mineral-rich conditions have been reported [2,3,5]. In the literature, however, electrochemical investigations of Se redox transformation have mainly been limited to interactions with materials such as gold (Au) [19][20][21][22][23][24][25], platinum (Pt) [26,27], and silver (Ag) [22,28], offering little geochemical relevance. The role of natural semiconducting minerals such as pyrite (FeS 2 ) and magnetite (Fe 3 O 4 ) in Se redox cycling has been experimentally investigated [29][30][31][32]; however, the research approach has been limited to batch experiments combined with spectroscopic analysis, and, especially, little is known about interactions between Se and galena.…”