Electrodeposition of Indium-Tin Alloys from EMI·BF₄·Cl Melts

Abstract

The electrodeposition of indium-tin alloys on a platinum electrode from EMI·BF₄·Cl melts was investigated by cyclic voltammetry and potentiostatic electrolysis. The cyclic voltammogram of the melt containing 0.1 mol kg⁻¹ InCl₃ and 0.1 mol kg⁻¹ SnCl₂ presented two broad reduction waves on the cathodic scan from a rest potential and three oxidation waves on the reverse scan. The electrodeposits obtained by potentiostatic electrolysis were found to be the mixture of tin and InSn₄, of which the average mole ratio of indium contained in the electrodeposits increased with decreasing electrolysis potential in the range from −1.1 V to −1.4 V vs. Fe(III)/Fe(II).