Electrodeposition of Cu2Se Semiconductor Thin Film on Se-Modified Polycrystalline Au Electrode

Abstract

This study describes the electrodeposition of Cu2Se thin films with a two-step approach that is based on the initial modification of polycrystalline Au electrode with a selenium overlayer followed by a cathodic stripping of the layer as Se2- in a 1 M lactic acid electrolyte containing Cu2+ ions. For this two-step approach to be effective, the Cu2+ reduction potential should be shifted to more negative potentials passed potentials for the reduction of Se to Se2-. This was accomplished by the complexation of Cu2+ ions with lactic acid. The resultant Cu2Se films were characterized by linear sweep voltammetry combined with electrochemical quartz crystal microgravimetry, UV-vis absorption spectrometry and Raman spectroscopy. Photoelectrochemical experiments revealed that Cu2Se synthesized thus, behaved as a p-type semiconductor.