Electrodeposition of tin in presence of К₂ТiО₃

Abstract

The abnormal influence of potassium metatitanate on the rate of the deposition of tin from stannate electrolyte is discussed: introduction of 1 mmol/L К2ТiО3 into working solution causes a fivefold increase of partial current Sn(VI) → Sn0 and, respectively, the current output of tin. The analysis of the correlation of potentials' values which are installed during the process of electrodeposition of microcomposite material was carried out. The correctness between the potentials' values and sustainable forms of precipitated component at a specified pH value was determined. The possibility of formation the titanium hydride is shown in these conditions. A sharp change in morphology of the tin sediment surface in the presence of additive К2ТiО3 in the tinning electrolyte is reviewed. The single-phase nature of the obtained micro-composite material including tin and titanium is proved. To explain these facts a scheme of electrode process is proposed, whereby SnO32– and TiO32– ions are reduced with hydrogen at the cathode, where the product of metatitanate-ions reduction is titanium hydride which is capable of catalysing SnO32– reduction. The suggested scheme also explains the changes in the morphology of the sediment surface. The growth of the needle crystals of tin which segregate in the presence of TiO32– ions takes place on titanium hydride active centers.

Keywords

• tinning
• potassium metatitanate
• microcomposite material