A voltammetric study of the electrodeposition of CuInSe 2 in a citrate electrolyte

Abstract

The electrodeposition of CuInSe 2 (CIS) on a Mo substrate has been studied by cyclic voltammetry from an acidic electrolyte containing citrate ions as a complexing agent. It is shown that the electrode reactions occurring on a Mo surface and on a Mo-modified surface, i.e. presenting indium-compound nucleation sites (Cu x In y Se or In y Se) are not the same. The presence of these nucleation sites is responsible for the non-reduction of Cu x Se on the electrode. The effect of the CIS substrate on the reduction potential of Cu 2+, In 3+ and Se 4+ in separate citrate solutions is examined. Evidence is given for the copper and indium deposition by a surface-induced deposition mechanism and for the Cu x Se formation by a co-deposition mechanism.