Effect of Cd(II) on electrodeposition of textured PbSe

Cathodic electrodeposition of PbSe from acidic aqueous electrolytes containing Se(IV), Pb(II) and Cd(II) has been investigated. It has been found that [100] oriented growth of PbSe crystallites takes place in some regions of Pb(II) and Cd(II) concentration. Electrosynthesis has been carried out under conditions of underpotential deposition of lead adatoms (Pb ad) and overpotential deposition of Se. It has been established by cyclic voltammetry that at electrodeposition potential E = −0.30 V (versus Ag/AgCl) underpotential deposition of Cd ad on Se atoms of the PbSe structure also takes place. Adsorption of Cd ad and Pb ad is irreversible due to the formation of the chemical bonds Cd adSe and Pb adSe. The presumption has been made that the mechanism of the Cd(II) effect consists in selective adsorption of Cd ad on faces of PbSe crystals and inhibition of underpotential deposition of Pb ad.