Contribution to the Study of an Electric Copper–Tin Cell Using Sulphuric Acid as Electrolyte. Effect of the Acid Concentration

In literature, some cells using Sn and Cu are described, but they usually use tin sulphate and copper sulphate as electrolytes. The concern of the present study is an electric copper-tin cell using sulphuric acid as electrolyser. The two electrodes, Cu (positive electrode) and Sn (negative one) are dipped in the sulphuric acid solution. Several cells were made, with different concentrations of the acid, in purified water. For each cell, the electromotive force E and the intensity I were measured. The output electric power P was calculated. The plotting of E against I and P against I showed the influence of the concentration on the curves. Then some selected intervals of E were chosen. For each interval, the average value of E was calculated. In addition, the average values of the corresponding I values of the intensity I were calculated. Those average values were used to make new plottings which showed less influence of the acid concentration on the curves. From those curves, the internal resistance r and the potential difference V of the cell at room temperature were determined. The experiments showed the presence of white tin sulphate and blue copper sulphate as deposits on the electrodes. Reactions occurring at the electrodes were discussed, including the hydrogen evolution reaction steps. Tin sulphate is interesting because it can be used as anode material for lithium secondary battery. Moreover, it can yield tin dioxide which is an n-type direct gap semiconductor, with an interesting band gap, and can be used as a material for photovoltaic conversion.

Lien d'accès : www.scirp.org/journal/paperinformation?paperid=150523

Pour consulter : https://www.scirp.org/pdf/ojapps_2313677.pdf